Wednesday, November 30, 2005

Classic evolutionary biology texts   posted by Razib @ 11/30/2005 11:56:00 PM

Mark Ridley's companion website to his book Evolution has some sample chapters from the Great Books of evolutionary biology. The Fisher, Haldane, Kimura and Wright chapters are the ones I would focus on, but, you all know my biases in terms of what interests me in evolutionary biology.

Covering up your face and smothering liberalism   posted by Razib @ 11/30/2005 05:17:00 PM

This long feature about the tendency for many young Muslim women to veil themselves in Europe is interesting. Granted, the author clearly abhors the trend, and much of the text is impressionistic, but with the Shabina Begum affair, it seems apropos. Back when I was a pretty doctrinaire libertarian I used to joke about Maggie Thatchers quip that "there is no such thing as society." No longer, humans are social creatures and the norms that we espouse shape how we interact with each other, social conservatives and communitarian liberals both draw from a deep vein of human reality. My ruminations on religious pluralism should make it clear that I think increased diversity will generate social anomie.1

In the specific case of women declaring that their taking up of the hijab or niqab is a personal statement (i.e., "I am no longer evaluated for my sexuality"), I think in most cases it is clearly fabulation. My experience on the "inside" is that the number one reason given within the community is that the only men that should see women are their closest male relations and their husband. But an important social and psychological parameter has to be the need to demarcate group barriers. In One People, Two Worlds: A Reform Rabbi and an Orthodox Rabbi Explore the Issues That Divide Them, the Reform rabbi comes close to taunting the Orthodox scholar1 about the fact that he "dresses like a 17th century Polish nobleman." Now, granted, this jab was partly a reaction to the fact that the Orthodox scholar nakedly questions the Reform rabbi's Jewish authenticity repeatedly. I was interested to note that the Orthodox scholar finally responded by making an analogy to a girl with tatoos and piercings who wishes to express difference and distinction from society. I have used this analogy in the context of women who ostentatiously (in my view) demand acceptance of both the most extreme forms of Islamic "modesty" as well entering into the public world where they are exposed to a level of interpersonal contact that would be shocking to "traditionalists." I recall as a child listening to my father expressiong confusion upon hearing of a woman who he knew of who had recently had a "religious awakening" and veiled herself...but remained at her job as a loan officer at a bank!!! If you do not understand my father's confusion, the common interpretation of shariah bans interest.

The last example suggests that in the case of veiling we need to decompose two aspects of the issue, 1) individual/personal driven factors, 2) the social-cultural context. Many of the women who are causing the greatest social tension do so because they juxtapose a modern and pre-modern worldview simultaneously, and demand that they be accepted on their terms. On a social-cultural level the withdrawl of women into purdah would be less tenditious simply because their visibility and friction with the mainstream would be mitigated. On the other hand, students and professionals who assert their modesty make it an issue by their projection into a world that does not share or understand their purported values or religion. I say purported because the simultaneous assertive modernity in goals (i.e., becoming a professional) of some Islamist women and their appeal to a melange of progressive (self-respect, liberty) and religious ("my religion demands I do this") talking points is a disorienting phenomenon which I don't see the mainstream being able to grapple with very well even though its legitimacy could be questioned through several angles of deduction from espoused axioms. When someone asserts that their religion demands a particular set of actions or beliefs, there is often a lack of retort that it is actually their interpretation of their religion. Without the latter there is an implicit marshalling of an entire religious tradition in the service of their personal opinion. To use another case as illustrative, I recall in high school an acquaintance of mine who declared in biology class that their "religion said that evolution wasn't true." I happened to know this individual and asked to confirm that they were Roman Catholic, which they assented to, at which point I offered that Pope Pius XII stated in an encyclical in 1950 that evolutionary theory was reconcilable with Catholic belief. This burst my acquaintance's bubble rather well.

Another issue is the social stress that different cultural mores induce. Most non-Western, and frankly, non-Anglo-Saxon, cultures have a different idea of "free expression" than is norm in the Anglo-Saxon tradition. The chilling of speech offensive to Muslims in Europe is a harkening back to the all-to-natural human norm. The attack on a theater in England by Sikhs was bestial. Not that absolute defense of freedom of speech is a universal characteristic of even all Americans, I recall back during the 1990s that William Donohue of the Catholic League floated ideas about enforcing sanctions against blasphemy via publically accepted community standards. In Catholicism and American Freedom I got the distinct impression that the Irish and Irish American hierarchy of the Roman Catholic Church were uncomfortable both with the pluralism of American society and its minimal protections for the dignity of the Church.3 In fact, as the 20th century wore on Roman Catholic activists who had battled the WASP elites and Know-Nothings shoulder-to-shoulder with Jewish intellectuals felt betrayed when the latter would periodically align themselves with secular anti-clerical WASPs to attack the Church as an anti-democratic institution. Donohue didn't have a coherent heuristic when queried in depth, but clearly there are those who would not shed tears at the death of liberty for Diderot.

I bring up the Roman Catholic example to emphasize to those sanguine about the rise of muscular Islam that elbow room offered to a marginal minority might be a tool used against the liberal order over the long term. Concessions in the interest of expediency and tolerance may be the first cracks in the high stress edifice of modern liberal democracy predicated on individual rights. Additionally, I believe the liberal democratic system is buttressed both by a particular relation between the state and individuals, and the pairwise interactions between individuals themselves. Clearly there are many segmented societies, but their social dynamics are often less than ideal. If social and political legitimization is granted a minority of "activists" from the increasing panoply of diverse communities, I suspect we will see a future where every man can be a Sharpton. As individuals and communities many will still thrive, but I believe the world will suffer the lack of liberal-individualistic witness.

What does the liberal democratic nation-state stand for? Well, sometimes it is easiest to define what one doesn't stand for....

1 - Contrary to the title, Yaakov Yosef Reinman declares himself a scholar of particular legal issues, not a rabbi.

2 - The point of this post is that liberal individualism is good, so some social anomie is OK by me. My point is that systems have breaking points, and when you transform a society characterized by gentle graded variations into one clustered around particular modes the primary vehicle of social organization and expression will shift from the individual to the groups.

3 - Attacks against the Church, many of them clearly libelous, were not generated by secularists as much as Protestants in this case. Ironically, the Roman Catholic Church, despite its lack of affirmation for the separation of church and state until deep into the 20th century, was probably the single most importance vehicle for the push toward non-sectarianism in public schools from the 1850s on.

Functional Variant in a Bitter-Taste Receptor (hTAS2R16) Influences Risk of Alcohol Dependence   posted by Razib @ 11/30/2005 07:40:00 AM

A new study in The American Journal of Human Genetics which relates to taste sensitivities and alcoholism:

...Individuals with the ancestral allele K172 are at increased risk of alcohol dependence, regardless of ethnicity. However, this risk allele is uncommon in European Americans (minor-allele frequency [MAF] 0.6%), whereas 45% of African Americans carry the allele (MAF 26%), which makes it a much more significant risk factor in the African American population.

From the discussion:

...To assess the distribution of the K172 allele across multiple populations, we typed this SNP in the Human Genome Diversity Project-CEPH Human Genome Diversity Cell Line Panel, which includes 1,057 individuals and represents 52 different populations (Cann et al. 2002). The MAF for rs846664 had a range of 10%-44% in African populations, but it was not detected or was present at very low frequency in non-African populations.

I talked about the K172 allele before in my post A bitterly positive sweep.

Tuesday, November 29, 2005

Notes   posted by Razib @ 11/29/2005 09:39:00 PM

I was checking out NuSapiens and noticed that he'd been nominated for Best New Weblog on something called The Weblog Awards. First, congrats to Nu, he is certainly one of "Our Crowd." Second, on a lark I decided to see if gnxp popped up, and I noticed that Jeff of Beautiful Atrocities nominated us for Best Group Blog. Thanks Jeff! Seems a little weird that there isn't a "Best Science Blog" category though (and I would vote for John Hawks FYI)....

Pinker on Ashkenazi IQ   posted by Razib @ 11/29/2005 07:16:00 PM

Steven Pinker is lecturing on Ashkenazi IQ in New York City in 2 days. If any GNXP reader who lives in New York wants to check it out and report back on what he says, the tickets are $11. Via Steve.


Unnatural groups   posted by Razib @ 11/29/2005 05:52:00 PM

We have talked in detail about the problems with group selection before, so before someone assumes that I am promoting that thesis in the generality I want to caution that I am not. But, it occurred to me today that I am convinced that a high ratio of intergroup:intragroup variance on cultural shibboleths is attainable. If your tribal members are characterized by a splotch of red paint on their forehead, while your traditional rivals brandish green forehead splotches, I think one can safely assume that variation of forehead color between the groups exceeds the variation within the group. This is in contrast to genetic variation, as neighboring groups (e.g., Serbs and Croats) will likely exhibit far more within than between group variation, in other words, the two population subsets will intersect over the preponderance of a given sample space.

In contrast to the genetic case cultural shibboleths can be directly and consciously manipulated. A trivial case would be the semi-hostility that was common in my middle school in western Pennsylvania when the Steelers and Browns would play each other. Sports ties and affinities are partly heritable, but, I also know of many individuals who consciously chose to diverge from the conventional familial allegiances to "make a personal statement." Jerry Seinfeld once remarked that what you are really rooting for are the jerseys, if a given player is traded to a rival team you are likely to detest him, simply because he has switched sides. I would contend that this phenomenon, often puzzling to those who have little interest in organized professional sports, is not learned, but cued to innate cognitive mechanisms. Recall that Constantinople was almost destroyed by rioting as the rival chariot team factions of the Blues and Greens joined forces against the imperial regime of Justinian and Theodora, not only are these passions relating to sports not modern, they can be extremely powerful in mobilizing group action.

Research reported in The Nurture Assumption and Not by Genes Alone suggest that a reflexive "groupishness" does exist in humans. Some of this groupishness seems almost perverse, for instance, studies which show that people tend to give more to individuals who they don't know, and will never meet again (controlled psychology experiments), when those individuals are arbitrarily labeled as members of the same meaningless group (e.g., "you are people whose favorite brand of cereal is Cheerios, while the other group likes Frosted Flakes"). But taking into account the behavior in relation to sports teams, I don't know if we should be that surprised. In Grooming, Gossip and Evolution Robin Dunbar argued that the maximum size of "natural" social units probably does not exceed more than a few hundred individuals. By natural, I mean social groups which don't need to be mediated by legal coda or formalized rules, but rather are managed through direct interpersonal interactions. It may be that there is a structural constraint upon how far the human mind can scale (the combinitorics of modeling social networks implies exponential increase in complexity as the number of individuals increases). It might also be that groups were never much larger than a few hundred individuals. I suspect it is likely a combination of both, though the former is probably a cap (to some extent) on the latter.

In any case, one could posit that for the vast majority of modern human existence small groups have been the operative units of human organization. One could take this to be the environment under which our innate intuitions were shaped. There are debates about the extent of massive modularity and the extent of hard-wired innateness. I will ignore the details and assert that though the extent of innateness may very, it seems highly plausible that some "mental organs" do exist. Language for instance is a good candidate. A minimal degree of innate social competence is also another one (a Theory of Mind). There are some that are fixed in human populations, while others may vary as a function of group, and likely there are many which vary throughout the population (perhaps because Evolutionarily Stable Strategies coexisting). But in any case, the omnipresence of groupishness across human societies indicates that it is a trait which has had widespread value, just as language has. This doesn't mean there has to be a "group module" in the brain, lodged within the "social organ," rather, there might be a few simple integrated heuristics, starting with "do with the majority does," which generate the groupish behavorial phenotype.

I began thinking of the idea that humans are adapted toward cuing onto somewhat absurd shibboleths as group identifiers after re-reading this old post of mine over after Matt McIntosh quoted me in regards to how people have problems categorizing groups in the modern world. The gist of what I was saying is that it makes sense that categorization schemes that are optimized for small groups would be maladapted to the modern world where groups have become much larger and amorphous. This post is an attempt to be a bit more clear in regards to that point: in the pre-modern world small groups could enforce on group identifying markers or behaviors upon members to a very high degree, ergo, intergroup variance could be maximized so that generalizations would carry a great deal of weight and predictive power. But now consider modern American Jews. Many Jews by declaration eat pork, enjoy shrimp and work and play on Saturdays. But they are still "Jews." Some still practice traditional Rabbinical Judaism, which was dominant between 500 and 1800 in some form throughout the Jewish world, but this group is not numerically the majority of identified American Jews. Infact, one could argue that in regards to many values non-Rabbnical Jews and gentiles now have more in common than non-Rabbnical Jews have with those who adhere to halakah in a strict fashion. In a similar vein, in The Future of Religion Rodney Stark and William Bainbridge found from survey data of habits and preferences that conservative Christians are a cultural outgroup in relation to non-conservative Christians and seculars. Even though Christians notionally belong to one group, in practice the norms and values of believers in this religion in the United States exhibits such a high level of intragroup variance that the "Left" half of the religious distribution intersects almost perfectly with the values of secular Americans who disavow any religious values or beliefs.

The big picture point is that we live in an age of unnatural groups and coalitions, where shibboleths that once might have had life and death implications (i.e., your tribe abandons you if you violate their taboos) have become cross-cultural affairs, and those groups now encompass billions (Christians and Muslims). Where in groups of 50-200 innate cognitive mechanisms could work to enforce strict adherence to a host of common practices and values to a group demarcated by narrow set identifying practies and beliefs, the same notions of group identity are now abstracted to "believers in Christ" or "the Ummah" where only the core practices and beliefs themselves are points of commonality. In pre-modern times groups were smaller, and lived in close proximity, today there is far less possibility of enforcement values across continents. Muslims might not eat pork, but I know from personal experience that South Asian Muslims prefer Indian food to Arab food, and that Arab Muslims prefer Eastern Mediterranean food, regardless of religion, over the food of Pakistan. Nevertheless, the same cognitive mechanisms which react to other groups can get triggered and make us react as if a group of 1 billion was functionally equivalent to a group of 100, even though the reality on the ground might be characterized by a great deal of variance in practice. A tribe of 100 is a far easier entity to generalize about than a tribe of 1 billion becuase a tribe of 100 can synchronize their practices and preferences far more easily. One might even ask if there can ever be truly a tribe of 1 billion in any real sense. One can see that these pancultural and continental groups, often under the aegis of universal religions, attempt to recapture the reality of small groups via their rhetoric of brotherhood and fellow feeling. And to some extent, it works, though not perfectly. The imperfection explains the temporary coexistence of liberal and segregationist Democrats within the same party for decades. In explains the modern day coexistence of libertarians and social conservatives within the Republican party. Residual notional affinity, often derived from past short-term utility driven alliances, can have a strong cohesive effect. But nevertheless, the reality is that the dynamics of the two structures, small groups and large quasi-groups are different on many points, and that is where our mental models start turning out unsatisfactory suboptimal results. The reality is that though liberal and conservative Democrats were of the same official kind, they divided their loyalties and had a host of other affiliations which worked at cross-purposes with their political identity (ACLU vs. White Citizens' Councils). Multiplicity of group allegiance has always existed, St. Paul was a Jew, a Christian and a Roman citizen simultaneously, but, I would argue that the differentiation of identities has exploded in the modern era as small scale groups have dissolved in the face of modern nuclear families, consumerism and geographical mobility, and the power of modern communication which has resulted in the dominance of the macrogroup in the mindshare of most individuals (i.e., American vs. over resident of East Village, Muslim as opposed to a citizen of Britain!). The synergy between our cognitive templates and the power of grand group rhetoric result in the disjunctive tendencies in discourse and practice in everyday life.

Addendum: I could go on for many pages on the many examples of disjunction between a) macrogroup identity b) reality on the ground and c) the tendency to extrapolate lower order relevant cognitive biases onto a), and the tensions it causes with b). But, I want to suggest on example that I have wondered about, in part because of my own ignorance in this area: language. One of the major issues I would have with Cavalli-Sforza's charts where he shows the concordance between languages and genes is that it ignores the reality that while gene frequencies are usually clinally varying as a function of space, languages are more sharply differentiated. Wait though, back up a minute...a few years ago I read in The Power of Babel by John McWhorter that the sharp boundaries between Slavic languages in the Balkans are artificial, that in reality the dialects graded into each other clinally. McWhorter said to the effect that "Bulgarian" and "Macedonian" on either side of the respective borders of these two nations would likely exhibit more similarity than two dialects of "Macedonian" at opposite ends of the nation. I know that in relation to Turkic languages this is clearly true, that the different national languages (i.e., "Uigher") are to some extent a hodgepodge of dialects thrown together due to the vicissitudes of history.

OK, so those sharp boundaries aren't always real. But it gets more complicated, because I'm sure you would object that "national Bulgarian," which is the official language, is standardized and sharply differentiated from "national Macedonian." Fair enough, but that gets into the issue of diglossia, the tendency for their to be a "high" elite literate language and a "low" dialect. While the high written languages might be distinct the low dialects grade into each other because of their scales of variation. A few years ago something really strange happened to me "second language" is Bengali. Normally, the few Hindi movies I have watched I could only really make out 25% of the words clearly (depending on context and cues), so that they were basically unintelligible to me. When I heard spoken Hindi, or its sister dialect, Urdu, usually uttered by elite individuals (they almost always had Ph.D.s or M.D.s), it was also basically Greek to me (not quite, but it wasn't intelligible in more than the vaguest sense). Nevertheless, an acquaintance passed recently to me a print story in a English newspaper where there was an exact transliteration of the local argot of eastern Uttar Pradesh state, where Hindi is the official language. And guess what, I understood 80% of it! And the honest truth is that "high Bengali" is almost as Greekish to me as Hindi. So here we might have a situation where the colloquial dialects across a wide geographic range share more commonalities than the elite languages which serve as their variant national vehicles.

The whole point of that digression is that this shit is complicated. If you think I have a hard time being pithy, well, you try to wrap up those nested realities and relations into a few sentences (that's a rhetorical dare).

Addendum II: Another tendency, which I'd like to emphasize the back-projection of modern perceptions of differences between factions. To give examples, the Blues and Greens in the Nika riots are often said to be proxies for the aristocracy and aspiring mercentile classes, respectively. My understanding is that this is grossly over-exaggerated in the attempt to find a 'rational' explanation from the factions. Similarly during late republican Rome the populares are often portrayed as 'progressive' and the optimates as the 'traditionalists.' The reality is that the optimate dictator, Sulla, was as 'traditionalist' as the modern Chinese state is communist. The typologies gloss over the fact of capricious and stochastic nature of factional alliances contingent upon personal relations and random acts of history.

Sunday, November 27, 2005

Ethnic Segregation in Britain: Part 2   posted by DavidB @ 11/27/2005 03:33:00 AM

In a recent post I commented on some research by Ludi Simpson and colleagues. I said I would return to the claim by Simpson that the main factor in the growth of the ethnic minorities in Britain is the age structure of their population, and not continuing immigration or higher fertility.

Simpson's press releases say, inter alia:

After a couple of generations... the population growth of these groups [Black and Asian] will have slowed and probably stopped... Fertility [of ethnic minorities] has reduced rapidly from the high levels associated with immigrant families. It is the youthfulness of immigrant workers and therefore their low mortality which has caused population growth, not high fertility, and not further immigration.

A report in the Guardian says:

Immigration is not the reason for increased numbers of non-white Britons over the past decade... the increase in the number of non-white Britons is due to demographics rather than immigration. Ethnic minority populations are younger and have fewer elderly people than white communities. The number of Asian and black people is increasing because fewer die from old age and they have more women of childbearing age relative to white people. The author of the study, Ludi Simpson, said: "The common myth is that the growth of the ethnic minority population is due to immigration. That's not true - it is more due to the growth of [ethnic minority] people born in Britain."

These statements are unclear as to whether the growth of the ethnic minority population is wholly or just mainly due to the age structure of the population, and whether fertility of ethnic minorities has already fallen to average levels, or whether this is a prediction for the future. But taking all the statements together, it seems that Simpson's position is as follows:

- the main factor in the recent growth of ethnic minorities ['over the last decade'] has been the age structure of the ethnic minority population, and in particular its relative youthfulness

- immigration has been only a minor factor

- fertility of ethnic minorities has already fallen substantially and can reasonably be expected to fall to replacement level.

Are these claims true?

First we need to establish the size of the increase in the ethnic minority population. In England and Wales (where most non-white ethnic minorities live), the non-white population increased by about 50% between the 1991 and 2001 Censuses, from 3.2 million (6% of the total) to 4.7 million (9% of the total). This is a very rapid increase for a single decade. Some small proportion of the increase may be due to the availability of a new 'mixed' category in the 2001 Census. On the other hand, it is likely that the 2001 Census understates the true increase, since there was substantial illegal immigration during the decade, and the Office for National Statistics has admitted that the Census total for 2001 is too low. The increase is also likely to have continued, if not accelerated, since then.

The increase can be attributed to three factors:

a. age structure

b. immigration


c. higher lifetime fertility.

Simpson's statements imply that (a) is the most important factor, and that (b) and (c) are relatively minor.

British immigration data are poor. However, figures for grants of settlement suggest that in the first half of the 1990s immigration from Africa and Asia was relatively low and stable, at around 50,000 per year. But this still represents an inflow of more than 1% of the ethnic minority population in a single year, and an increase of cumulatively around 15% in a decade, which would be a significant proportion of a 50% total increase. Moreover, immigration from Africa and Asia increased rapidly after 1997 (see pp. 14-15 of the ONS Social Trends for 2005.) By 2003 it had increased to around 100,000 a year, representing more than 2% of the current non-white population per year. There is no sign of any slackening. One relevant factor has been abolition of the 'primary purpose' rule for the admission of spouses since 1997. Under the primary purpose rule, spouses of existing residents were not permitted to settle in the UK if the primary purpose of the marriage was assessed by the Immigration Service as being to obtain entry to the UK. The abolition of this rule (which admittedly was difficult to apply) has increased the number of arranged marriages with spouses from Pakistan or Bangladesh. Another factor in rising immigration is the large increase in immigrants from Africa, often in the guise of 'asylum seekers' from Nigeria or Somalia. It should however be noted that there has also been a large increase in white immigration from Eastern Europe in the last few years.

Overall, it seems likely that about one third of the increase in the non-white population over the last decade can be attributed directly to immigration. This is hardly negligible.

The third element to be considered is lifetime fertility, usually expressed as the Total Fertility Rate (TFR) for women of child-bearing age. Ludi Simpson claims that fertility has already reduced rapidly from the high levels associated with immigrant families, and he suggests that it is likely to fall further.

I have not been able to find reliable recent ethnic fertility data for Britain (or England) as a whole, but there are some useful data for London in a study of 'Fertility of Ethnic Groups in London' by the Data Management and Analysis Group of the Greater London Authority in September 2003. This gives the following TFRs for women in London:

Black Caribbean.........1.70
Black African...........2.28
Black Other.............1.51

It will be seen that most groups are below the replacement rate (just over 2 children per woman), the exceptions being Black African, Pakistani, and Bangladeshi. It is noteworthy that the Indian TFR is among the lowest, though not as low as White. It is also clear that the TFR for Bangladeshis and Pakistanis is still substantially above the replacement rate, and more than twice the level for Whites. This may reflect the fact that a larger proportion of women in these groups are first-generation immigrants (see the comments above on arranged marriages). However, Black Caribbeans and Indians, with low TFRs, are among the largest minority groups, so it may well be that the average TFR for all non-whites in London is around the replacement rate.

London is not entirely representative of Britain as a whole. It is difficult for young married couples to afford housing in London, so there tends to be a high proportion of single people, including single parents in subsidised housing. But a large proportion of ethnic minorities in Britain live in London, so the London data on ethnic minorities cannot be badly misleading. If the average TFR for all non-whites is around the replacement rate, then Ludi Simpson may well be right in claiming that the overall increase in the ethnic minority population in Britain in the last decade has had little to do with higher fertility. I did not expect to find this result when I started digging, so I am obliged to draw attention to it. On the downside, the Pakistani and Bangladeshi groups, which are still increasing due to higher fertility, as well as other factors, are among those with the lowest employment rates and the worst educational performance. They are also those with the lowest rates of intermarriage with other groups. So the prospect of increasing concentrations of discontented, idle, Muslim youths, a la Francaise, cannot yet be entirely discounted.

Saturday, November 26, 2005

Ancient and Recent Positive Selection Transformed Opioid cis-Regulation in Humans   posted by Razib @ 11/26/2005 04:09:00 PM

Ancient and Recent Positive Selection Transformed Opioid cis-Regulation in Humans:

...In addition, the pattern of linked nucleotide and microsatellite variation among and within modern human populations suggests that recent selection, subsequent to the fixation of the human-specific mutations and the peopling of the globe, has favored different prodynorphin cis-regulatory alleles in different parts of the world.

John Hawks has detailed commentary. Some info on cis and trans regulation.

Clarification on "roots"   posted by Razib @ 11/26/2005 02:25:00 PM

Jim Bender links to my post where I express some frustration with tree based thinking in terms of human ancestry. He says, "I take that to mean that there is a great deal of mixing between the so-called races over time" [my emphasis]. Terms like "great deal" are insufficiently precise. Fst 0.2 is often used as a boundary number between low and moderate levels of population substructure, but it is somewhat arbitrary (1 migrant per generations yields 0.2). My overall point was that beyond a few generations in the past our intuitionally grounded concepts start to deviate from how gene genealogies work. 50 generations into the past I have an x number of distinct ancestors, but a y number of these ancestors show up many times at the tips of branches. In talking about populations the easiest citations are mtDNA and NRY, the male and female lineages...which causes problems in adding empirical support to overall assertions derived from an understanding of the details of how the tree plays out as you progress back in time, because mtDNA and NRY isn't always a good match (concordance) with the rest of the genome.

A Genetic and Cultural Odyssey   posted by Razib @ 11/26/2005 01:21:00 PM

As promised, I did read A Genetic and Cultural Odyssey, the biography of human geneticist L. L. Cavalli-Sforza. I have to say that it was a very uneven work, but neither of the two authors are writers by profession (an anthropologist and geneticist). The main thing I took away from the book was that I will be curious to check out Cultural Transmission and Evolution,1 which is a theoretical work that attempts to transpose the models of population genetics into a cultural framework, and Bryan Sykes is a grand-standing ass. Since there are other data points in regards to Sykes, I am prompted to believe Cavalli-Sforza's side of the story.2

There are short sketches of Cavalli-Sforza's early work in bacterial genetics that might surprise some (I was aware of this from reading I'd done on R.A. Fisher), but there seemed to be a disproportionate focus on his work in relation to anthropologists. In particular, his somewhat scientific-reductionistic attitude toward the discipline, in contrast with the zeitgeist of the field within the past generation which has focused on criticism and contextualization, almost to the neglect of model building or positive assertion. Of course, the race-does-not-exist chapters are somewhat hilarious in their attempt to dance around semantically. A key issue might be that race-does-not-exist in the way that it is conceived of colloquially, idealized discrete types, but it does exist as predictable lumps within the soup of clinal variation. Sometimes the authors make embarrassing statments, for instance, "Pygmies are short because of the wet tropical climate." The adaptive story is probably a lot more subtle than that. This is also pretty egregious in light of their emphasis on the neutral portion of the genome, as opposed to functionally relevant loci. Some of the unevenness might have been due to the fact that the two authors wrote alternating chapters, but that's an explanation, not an excuse.

Of course, how much can you compress into ~200 pages? The major problem is that I'm not sure the authors knew what they wanted the book to be, the mathematical footnotes were interesting, but anyone who would take an interest in such details would almost certainly wince at the superficiality of the prose used to impart the concepts.

Addendum: One good thing about this bio though is that it shows how much Cavalli-Sforza's life intersected with other prominent biologists, Joshua Lederberg, R.A. Fisher and Anthony Edwards. Also, Lynn Jorde has reviewed the book, similar general impression from what I can gather.

1 - What utility do mathematical models have in discussing something as amorphous and intractable as culture? The reality is that mathematics can often clarify exactly what you are trying to get at, so the upside might be precision in communication more than a utility in regards to predictive value (that is, predictions made from the models might be trivially obvious).

2 - Why do I link to The Seven Daughters of Eve? First, it is copiously cited in the semi-popular literature. Second, if you take it for what it is (rather than what Sykes tries to claim it), I think it is a decent survey of the H. sapiens mtDNA literature circa 2000.

Friday, November 25, 2005

Islands and Shifting Balance?   posted by Razib @ 11/25/2005 05:41:00 PM

Living the Scientific Life has a great summary of this recent paper which suggested that islands can serve as sources for biological diversity via back-migration to continental sources. Am I the the only one to think of the Shifting Balance Theory? To be succinct, Sewall Wright and R.A. Fisher spent several decades disputing (PDF link) the importance of population substructure and random genetic drift as salient forces in evolutionary genetic dynamics (Wright tended to emphasize their importance to a far greater extent than Fisher). In this scenario, where there was diversification of the original colonizers on islands, it seems plausible that the rate of migration1 might have been low enough for substructure to become a significant parameter. Of course islands are special cases which are not ubiquitous, so the biggest take home message might be that evolutionary genetic dynamics needs to considered in context.

1 - Fst, which is a reflection of interpopulation vs. intrapopulation genetic variation, can be related to the # of migrations per generation via 1/(4Nm + 1), where N ~ number and m ~ proportion of migrants per generation, so that Nm is the # of number migrants per generation. 1 migrant per generation is usually sufficient to serve as a break on interpopulational differences. Random genetic drift's power is inversely proportional to N, so when the population is large there isn't much sampling variance which the 1 migrant has to work against, while in a small population 1 individual is a much larger proportion of the population. More here.

I am not a Muslim   posted by Razib @ 11/25/2005 04:29:00 PM

Just a reminder everyone, I am NOT a Muslim. Just saw a reference to me as a "Muslim guy" on a comment board in regards to evolution vs. creation (pointing to this site as a good read on the topic). I do not regard Islam as an ethno-religion like Judaism or Hinduism. Unlike the latter religions, creed, profession of belief, is a hallmark of Islam. I reject the creed, ergo, I reject the religion and do not identify as Muslim. Over at Sepia Munity I specifically changed my handle to "razib_the_atheist" because I got tired of people assuming I was Muslim from my name (thinking I am a Muslim was not the problem, the problem was that people addressed me as if I held beliefs common to Muslims, which resulted in some bizarre questions , i.e., "As a Muslim, don't you think you should speak up about the problems with Islam?"). Part of the problem I think with regards Sepia is that many of the people come from a Hindu tradition where there isn't such a close coupling of creed to religious identity, so my origin as a Muslim is given greater weight than I myself give it. In fact, I have noted that on the internet, where people don't know me in day-to-day interactions, there is far more emphasis given to my Muslim origin than in my regular life (where people assume I am of Hindu background from what I can tell in reference to consideration for my presumed vegetarianism). For example, several people have assumed that I might identify with civil rights issues in relation to Muslims because of my background, but the reality is that I don't (above and beyond my general libertarianish concern with such issues). I am not even averse to a legal name change if that is what is necessary to decouple myself from any Muslim identity (as I said, most people assume I'm Hindu despite my name, so I don't think it is necessary at this point). Also, unlike several acquaintances who are atheists of Muslim background, I do not identify as a cultural Muslim in any way, shape, or form (given Islam's traditional hostility toward unbelievers who was "born" into the religion, I see no reason that I should evince warm feelings toward the cultures in which it is embedded).

To readers of this weblog this is all likely superfluous, but I wanted this on the record, this isn't the first time that I have seen a reference to me as a Muslim on a message board. The fact is that on the personal level I am as irritated and offended by people associating me with Islam as a believer as a Muslim would be by an evangelical Christian telling them that they are "idol worshippers" (this happens!). This is an issue where in fact I feel comfortable being in agreement with evangelical Christians, because unlike more "cultural" religious traditions like Judaism, Hinduism or Roman Catholicism, they place primacy on belief and don't regard personal origin as particularly determinative ("born again" Christians of course must go through an experience of becoming "Christians" as adults, and Baptists reject infant baptism because of their emphasis on the primacy of personal choice).

PS: On my name, "Razib," it is actually simply a slight tweak on the name "Rajib," which is a conventional Bengali variant of the name "Rajiv."

Update: On my name, in kindergarten, my teacher, a naturalized American citizen of Dutch origin, had difficulty enunciating the "j" in my name and switched it to a "z." My parents call me "Rajib," as do the rest of my relatives and Bengali acquaintances from my parental generation. Everyone else knows me as "Razib," though truncation is a common tendency. Occassionally I run into someone who is "in the know" and they can't help but call me "Rajib," because that is the variant they are familiar with (if they knew someone named Rajib they invariably can't help but use that form).

Wednesday, November 23, 2005

An evolutionary education   posted by Razib @ 11/23/2005 07:52:00 PM

RMP over at EvolGen is starting a series called Detecting Natural Selection. I know a substantial subset of readers don't come out of a science background, so I think some might find it of interest. The first entry is up, if anything is a surprise, read the whole thing (eventually).

University Channel   posted by the @ 11/23/2005 05:19:00 PM

Something new

"A collection of public affairs lectures, panels and events from academic institutions all over the world -- for you to view, listen to, stream or download."

... not to be confused with the ResearchChannel

Tuesday, November 22, 2005

Man is more than one tree   posted by Razib @ 11/22/2005 09:21:00 PM

This is a short post which I will elaborate on later in a broader biological context, but Richard Sharpe's comment is something I want to respond to real quick: "If Greeks are Caucasian, then...Just how do you designate yourself...."

First, I'm not white, my ass is a rich brown, ergo, I'm not "Caucasian." The nerdy amongst us though might be familiar with the term "Caucasoid," which shares a relationship with Caucasian (there were very few non-white Caucasian/Caucasoids in the country when these terms became common). Well, operationally I don't think South Asians should really be considered Caucasoid (though Middle Easterners should, Middle Easterners-Europeans are a monophyletic clade in relation to Brownoids). On a phylogenetic tree, if I had to make one, I would make Caucasoids and Brownoids (my term) a monophyletic clade in relation to other races of man.

But there's a serious problem with this in my opinion. In The Real Eve Stephen Oppenheimer spun a grand genetic-historical narrative which culminated during the Last Glacial Maximum, about 30,000 years ago. It is from this point that Oppenheimer traces the origins of modern races. He states flat out that admixture has been minimal. Perhaps. Perhaps not. The problem with Oppenheimer's story is that it is rooted in mtDNA, which is passed only through the female line. This is neat, because it eliminates recombination between lineages, so you get a clean cladistic tree all the way back to a common ancestor with all the putative ancestral character states. But the vast majority of our DNA is recombinant, and not passed uniparentally. You look at many Latin Americans, and the mtDNA will tell you they are cousins to East Asians, while the NRY (passed through fathers) will tell you they are Iberians. This is the most extreme case, but I doubt it is the only one.

So back to Richard's question. The problem I have with answering stuff like this is that I'm a melange, as all people are. I can say that I suspect it is likely that vast majority of my ancestry can probably be traced to the South Asian subcontinent around 10,000 years ago, but my NRY and mtDNA might say something different. Our full ancestral complement does not decompose itself into a bushy cladistic tree, it a reticulated mish-mash, like a ball of spaghetti. I mean, we're not asexual, right? We're one species across which genes can flow in a sweeps. Well, tell that to the authors that are making tidy advances based on books that pedal neutral lineage markers as the family-tree writ large. Genealogy is big bucks, even in quasi-scientific garb.

And who forgot selection? (Natural and social)

P.S. I have to say, about 2/3 of my scientific posts probably are derived from a question from the comment boards. A lot of the time it is even a 2nd or 3rd order idea, not a direct response. So thanks.

The New White Flight   posted by Razib @ 11/22/2005 03:36:00 PM

I didn't know this article in The Wall Street Journal was free, but it is, so I'll link to it: The New White Flight: In Silicon Valley, two high schools with outstanding academic reputations are losing white students as Asian students move in. Why? To some the article might be revelatory. This quote is very interesting to me:

Cathy Gatley, co-president of Monta Vista High School's parent-teacher association, recently dissuaded a family with a young child from moving to Cupertino because there are so few young white kids left in the public schools. "This may not sound good," she confides, "but their child may be the only Caucasian kid in the class."

Why should this matter? I don't know, I was the only non-Caucasian kid in most of my classes between the age of 6 and 18, and I wasn't traumatized, but perhaps whites aren't as ethnocentric and exclusionary as the Asian Americans which dominate this Cupertino High School (you know how well South Asians and East Asians cooperate! Hindi, Chini, Bhai Bhai!). From reading the article it seems to me that some Asian American parents, usually first generation immigrants, are bringing the "cram school" mentality to these shores. I'm all one for scholarship and academic competition, but to some extent I suspect that for the majority of kids this simply becomes a self-perpetuating cycle, like high stakes standardized testing.1 If I had a normal child, a kid below 3 standard deviations above the mean in IQ and without any specific drive and passion that could be optimized by attending these sorts of schools, I might also be hesitant to allow them to become ensconced in the kind of ends driven atmosphere sketched out above. I am skeptical that much value would be added to their cognitive toolkit over the long term in relation to the marginalization of normal avenues of socializing and the participation in common rites of passage which confer a sense of full citizenship. Nevertheless, I will be convinced at white terror of Asian American hegemony when I read about flight from Cal Tech, MIT and Berkeley, as Cal Poly, RPI and the Cal State schools start receiving Caucasian applicants who reject the former institutions because of their yellow cast.

But note throughout the article the transposition of subtle talking points and background assumptions normally utilized in articulation of the need for ethnic sensitivity toward members of underrepresented minorities in the context of whites. Over the last few years the cultural center has been tacitly cheerleading the transformation of this nation into a minority white polity where racial awareness is acceptable for minorities. It seems possible that a byproduct of these the two phenomena indicated above might be the organization of whites as a racial interest group. Society isn't a linear system, so who knows.

1 - Or the devaluation of a bachelor's degree in the United States because of widespread access to university educations, and the pressure from society for all children to at least make a go at it.

Ethnic Segregation in Britain: Spin or Substance?   posted by DavidB @ 11/22/2005 06:45:00 AM

There is a common belief that in Britain the different ethnic groups are becoming increasingly concentrated into different geographical districts, as 'white flight' reduces the proportion of whites in inner city areas, while ethnic minorities cluster together. The Chairman of the Commission for Racial Equality, Trevor Phillips, recently expressed the fear that Britain is 'sleepwalking to segregation'.

Recent research casts doubt on such claims. The research is by sociologists at the University of Manchester under Dr Ludi Simpson. (Google on "Ludi Simpson" and "segregation" for numerous reports.)

Simpson's own press release summary of the findings is as follows:

Our research suggests there is a lot of good news; in fact, there is more mixing. On balance there is neither retreat nor White flight. The larger populations of Black and Asian communities that have been highlighted are there simply due to natural growth; i.e. people having children. There are no Black or Asian ghettos anywhere in the UK where families of one colour are trapped. In all parts of Britain, the children of immigrants are moving away from so-called ghettos. After a couple of generations the mixing will be far more noticeable and the population growth of these groups will have slowed and probably stopped.

In a more detailed comment on the northern city of Bradford he says:

The broad picture that can be painted from these data is one of dispersal of a growing South Asian population from the inner city. This does not result in lower segregation because the inner city South Asian population is 're-filled' by natural growth (more births than deaths) and by immigration; there is some movement of South Asian families into the housing of White populations who move from inner city areas. Thus the index of segregation for Bradford as a whole has been stable, but this stability is the balance between several different trends.

He adds that recently released data from the 2001 Census supports the Bradford findings for most areas of Britain.

These findings have been widely reported in the Press, generally without criticism or analysis. For example, according to the Guardian:

The study also says that immigration is not the reason for increased numbers of non-white Britons over the past decade, and that "white flight" from inner cities is another myth... The study says the increase in the number of non-white Britons is due to demographics rather than immigration. Ethnic minority populations are younger and have fewer elderly people than white communities. The number of Asian and black people is increasing because fewer die from old age and they have more women of childbearing age relative to white people. The author of the study, Ludi Simpson, said: "The common myth is that the growth of the ethnic minority population is due to immigration. That's not true - it is more due to the growth of [ethnic minority] people born in Britain."

In further press notes Simpson says 'Fertility [of ethnic minorities] has reduced rapidly from the high levels associated with immigrant families. It is the youthfulness of immigrant workers and therefore their low mortality which has caused population growth, not high fertility, and not further immigration'.

This is interesting research, and it is useful as a corrective to unsupported myths. But it may create an equally misleading counter-myth. It is necessary to distinguish between the facts and the PC spin put on them.

The facts are that in inner city areas the proportion of ethnic minorities is increasing, while ethnic minorities are also spreading out into surrounding, previously all-white, areas. This pattern is almost inevitable because the ethnic minority population is growing. But even if the ethnic minority population were not growing, it is predictable that economically successful immigrants would wish to move away from poor quality urban environments, and into previously white suburbs and rural areas.

Whether the combined effect of these factors is regarded as increasing or reducing 'segregation' depends in part on how segregation is measured, which is not straightforward. (For some discussion of different measures see here.) But it is evident that by Ludi Simpson's own chosen Index of Segregation there is no overall reduction in segregation. The growth of ethnic minorities in inner city areas increases segregation, while the dispersal into surrounding areas reduces it. The two factors roughly balance each other. Simpson's own statement 'This does not result in lower segregation' could hardly be clearer. So if Simpson or others choose to headline the claim that 'integration' is increasing, this is giving only half the story.

I don't claim to know whether 'integration' in any useful sense is increasing or not, but one test of this would be to look more closely at where the 'dispersing' ethnic minorities are going. Are they dispersing at random into the surrounding areas, or are they concentrating in more localised districts? For example, some of the outlying areas of Leicester are far more heavily Asianised than others. Some suburban schools in Leicester are now mainly Indian, and schools are a good indicator of the extent of practical integration or segregation. A recent study by Burgess, Wilson and Lupton found that 'Looking at both schools and neighbourhoods, we find high levels of segregation for the different groups, along with considerable variation in segregation across England. We find consistently higher segregation for South Asian pupils than for Black pupils. The data also suggest that segregation tends to be lower for Black pupils where they are relatively numerous, but that no such attenuation exists for pupils of South Asian origin. Indeed, for these groups, segregation is higher where they are relatively numerous'.

There is nothing surprising about non-random dispersal of people with distinctive cultural and religious traditions. People will want access to appropriate places of worship, shops, etc. An important factor in directing dispersal to particular areas is the prevalence of Asian estate agents (realtors) serving mainly their own communities. This is not necessarily a bad thing, but it would be nice to know the facts, and not just prattle about 'integration'.

I was also intending to discuss the claim by Simpson that the main factor in the growth of the ethnic minorities is the age structure of their population, and not continuing immigration or higher fertility. But I will save that for another post.

Monday, November 21, 2005

Infidel Guy on TV   posted by Razib @ 11/21/2005 11:24:00 PM

For those of you who watch television, The Infidel Guy will be on ABC's Wife Swap next week. Apparently Reggie's wife is switching places with a pastor's wife, should be pretty tweaky.

Luca Cavalli-Sforza biography   posted by Razib @ 11/21/2005 09:46:00 PM

I just found out recently that a biography of Luca Cavalli-Sforza was published this spring, A Genetic and Cultural Odyssey. I'll probably be reading it over the Thanksgiving weekend, but I thought I'd give people a heads up around here since I suspect I'm not the only fan. The History and Geography of Human Genes is one of those seminal works which has really shaped the intellectual path I have taken. Over the years I have become progressively more skeptical about reading history from alleles frequencies, but Cavalli-Sforza's work is an interdisciplinary inspiration to this day. If a readable genetic monograph is your cup of tea, I also recommend Consanguinity, Inbreeding, and Genetic Drift in Italy. I picked it up a few years in Barnes & Noble in New York, and read most of it on the airplane. The frequency of aunt-nephew marriages in Sicily will make you wonder! Finally, Genetics of Human Populations is back in print, though the text isn't updated a lot of the population genetic models are becoming extremely relevant again to deal with the swarms of data that are the norm in the post-genomic era.

Immigration conversation   posted by Razib @ 11/21/2005 09:00:00 PM

As a naturalized American citizen, I point you to Michael Blowhard's immigration post.

New home   posted by Razib @ 11/21/2005 12:28:00 PM

As most of you probably noticed last week this site was down due to "support/billing" issues. Here is what was going on: this website regularly taxes the contractual parameters of every hosting service I've signed up for over the past 3 years. We never cross the line in regards to bandwidth or abusive scripts, but the traffic is enough even for static files. We've gone through 3 hosts, and each time the actions have become more peremptory. The last time they even refused to give me a back up of the site (I make one every 2 months, so that wasn't that big of an issue, and now that we are using BLOGGER there is a permenant archive of posts). The reality is that quite often webhosts throw out "deals" to lure customers because they know the vast majority of clients won't be using anywhere near the full capacity of their services. GNXP did use the full capacity, so ultimately, webhosts get stuck providing services for someone who is using more than their anticipated allotment. In the end, they simply point to a vague part of the contact and terminate the service (i.e., in this case "traffic abuse," i.e, too many web pages served, even though we stayed under the bandwidth quota and didn't run any intensive scripts).

But I'm now pleased to announce that two "friends of the blog," Elizabeth & Rick, have offered to host us. Hopefully there won't any unexpected outages in the future.

Sunday, November 20, 2005

Making babies   posted by the @ 11/20/2005 11:18:00 AM

Two stories have been ironically juxtaposed in time on the front page of the NY Times web site:
Hello, I'm Your Sister. Our Father Is Donor 150.
The Problem With an Almost-Perfect Genetic World

Most likely these stories got there because of the pictures of cute little kids. However, the coincidence makes for an opportunity to point out a bit of cognitive dissonance about the topic of genetics and reproduction.

First, let me point out that there's a lot of interesting discussion in these article and you should read them for that sake. I love that the half-siblings from sperm donors feel a kinship relationship despite the fact that many are first meeting in their teens (note half siblings are as related as [correction: Uncle/Aunt - Nephew/Niece pairs]).

However, some aspects of the sperm donor topic go unexplored. With a seemingly unlimited supply of sperm in the world, why are so many children being born from the same donor? The answer is, quite obviously, that some donors are more attractive to mothers than others. Since the only thing these donors are giving to their children are half a complement of chromosomes, the attractiveness is obviously in the genes.

Now consider the repro-genetics article. This article is better than most in that it doesn't consider the ridiculous (but often asserted) position that wanting to not give birth to children with disabilities literally implies that we want to destroy existing children with those disabilities or that we regret their existence in such as way as to value them less as persons. They consider more reasonable concerns, such as the fear that reduced incidence of children born with genetic disorders will reduce funding for treatments (a harm to the children already born). However, I would argue that none of this is an argument against screening -- we would not chose to give children these disabilities to increase funding -- but it is a legitimate issue to consider.

However, consider this segment:
"Where do you draw the line?" said Mark A. Rothstein, director of the Bioethics Institute at the University of Louisville School of Medicine. "On the one hand we have to view this as a positive in terms of preventing disability and illness. But at what point are we engaging in eugenics and not accepting the normal diversity within a population?"

Rothstein seems to be suggesting that extreme deviation from the population mean is an acceptable target for screening, but that (for example) variation within 3 SD of the mean should be off limits. I fail to see any good argument for such a differentiation.

Now let's tie these stories together. As I noted about repeated use of the same sperm donor, there is apparently a selection going on at the level of maternal choice of a sperm donor among men who are within the normal range of variation that Rothstein had in mind. This doesn't seem to be eliciting concern and neither should screening for abortion in that range.

It appears that "poor man's gene therapy", as Rothstein calls selective abortion, is already happening prior to conception and increasingly through prenatal screening. Looking forward: "Soon, though, pregnant women may be offered a gene-chip technology that can perform hundreds of tests at once for a few hundred dollars." Maybe not a microarray platform, but medium through-put genetic screening is already feasible using commercial technology.

Saturday, November 19, 2005

Power of the media - to make you look like a schmuck   posted by the @ 11/19/2005 02:04:00 PM

This article in the NY Times -- Googling Literature: The Debate Goes Public -- is an excellent example of the power of the media. If the publishers' and authors' guilds had a case to make to the public, they've failed here. If this the extent of the coverage, they've lost the PR campaign.

It amazes me to see the top down power of the media (and politicians -- for example Bush on ID) to swing public opinion.

Genes and Civilisation   posted by DavidB @ 11/19/2005 12:42:00 AM

[Added: using some browsers you may see some odd symbols in the following. These should be single quote marks.]

In a previous post on interracial marriage I suggested:

It is conceivable...that the distinctive achievements of European culture have depended on the prevalence of certain combinations of intelligence and personality which in turn depended on gene-combinations that are more common among Europeans than elsewhere, and which would become rarer if the European gene-pool were to merge with, say, the Chinese gene-pool. I don't know of any serious evidence for this, but I don't think it can be dismissed as absurd.

In comments there was a lot of discussion on this point, so I want to consider it further. The present post will give some reasons for being sceptical about any close link between genes and cultural achievement, while a second post will give reasons for not dismissing it as absurd.

I will not say much about intelligence, because the whole question of population differences in intelligence (as measured by IQ) is complex, and there is no shortage of previous discussion of the subject. I would just point out that on a timescale of millennia, the genetic basis of population IQ differences is not fixed. There are about 30 generations to a millennium, so with even modest selective influences on mean IQ (say, up to half an IQ point per generation), the observed differences between populations (around 15 IQ points plus or minus from the global mean) could be due to comparatively recent changes - by which I mean within the last few millennia, rather than deep in the Palaeolithic.

In any event, there is no reason to suppose that mean genetic IQ differs dramatically within Eurasia, so I will confine my discussion to Europe and Asia, with the obvious extension to people of recent European or Asian descent elsewhere. Within Eurasia, Europe has probably always accounted for a fairly small proportion of total population - less than a quarter - yet seems to have accounted for a very large share of cultural achievements. In his book on Human Accomplishment, for example, Charles Murray concludes that a majority - over 70% - of identifiable cultural achievement throughout the world since 800 BC can be attributed to Europeans or people of European descent.

Of course, Murray's statistics can be criticised. He bases them on biographical dictionaries and other reference works, which to some extent reflect the limited knowledge and interests of the compilers of such works. But it would be difficult to dispute that Europe has accounted for a disproportionate share of achievements in this period.

For the present purpose a more serious objection is that the cultural dominance of Europe depends on the period chosen for study. Europe has only taken the global cultural lead during two periods: from 500 BC to around 300 AD, and from around 1400 AD to the present (counting the USA as an extension of Europe). If a medieval (and probably Islamic) scholar had taken a survey around the year 1000 AD, he would have found China, the Islamic world, and India far more culturally developed than Europe. If we take 'civilisation' as dating back to around 3000 BC, Europe has been culturally dominant for only about a quarter of the time. All the main parts of Eurasia - Europe, the Middle East, South Asia, and the Far East - have at some time achieved high levels of 'civilisation'.

It would therefore be difficult to argue that European dominance is strictly determined by some advantage of the European gene pool. We also find that there have been sharp fluctuations in the relative performance of different countries or regions within Europe, with no obvious genetic basis. For example, in the 17th century Scotland and Switzerland were cultural backwaters, notable only for religious bigotry, but in the 18th century they were head-for-head the most creative places in the world, with such major figures as Hume and Adam Smith in Scotland, or Euler and Rousseau in Switzerland (see Note 1). Rapid changes of this kind should make us sceptical of any simple relationship between genes and 'civilisation'.

It is evident that cultural vitality depends in part on economic and political circumstances. Economic prosperity usually goes together with achievement in the arts and sciences, a striking example being the golden age of the Netherlands in the 17th century. Conversely, it is difficult to think of any case where prolonged economic stagnation or decline has been accompanied by great cultural achievements, though it is not incompatible with artistic charm and sophistication, as in 18th century Venice.

The shifting patterns of economic prosperity themselves are notoriously difficult to explain. Whole libraries of books have been written to explain why the Industrial Revolution occurred first in England, rather than anywhere else, but there is no consensus on the subject. Most explanations involve a combination of a least three or four different factors. It is likely that this applies to economic growth and decline generally.

On a global scale the cultural dominance of Europe since 1400 AD coincides with European economic growth and political expansion relative to other parts of the world. It is tempting to regard European dominance as somehow pre-destined, but it is not difficult to imagine circumstances - for example if the Chinese, rather than the Europeans, had occupied the Americas, or if the Mongols had ravaged Europe in the 13th century - where the balance of advantage would have favoured Asia.

And yet - I still can't help wondering if there is something special about Europe, that can't be explained just by some happy combination of historical and economic circumstances. From time to time - as in Greece in the 5th century BC, or Renaissance Italy - there have been dazzling bursts of creativity that to the best of my knowledge simply can’t be matched in any other region. Perhaps the most striking example is the scientific revolution of the 17th century, sometimes called the 'century of genius'. Simply to list the major figures should inspire awe: Galileo, Kepler, Gilbert, Descartes, Fermat, Torricelli, Pascal, Harvey, Huygens, Boyle, Wren, Hooke, Newton and Leibniz, to mention only some of the most obvious. There are few non-European scientific figures to compare with any one of these, let alone such a cluster within a single century. One of their most striking features - which applies also to other creative periods in Europe - is their intellectual ambition and courage: their willingness to overturn traditional doctrines in pursuit of truth (or personal glory!), even at risk of persecution. This seems to be a matter of personality as much as intellect. Granted that there are social and economic preconditions for such a flowering of creativity, can it be explained purely by environmental circumstances? Or is there also some specific basis in genetics?

In a second post I want to take a further look at the basis for scientific creativity, with a comparison of the history of science in Europe and China.

Note 1: I have counted the Republic of Geneva as part of Switzerland for this purpose, though in the 18th century it was not in the Swiss Confederation. Apart from Euler and Rousseau, other notable C18 Swiss include the Bernoulli family of mathematicians, the biologists Haller, Bonnet and Trembley, and the pioneering geologist H. B. de Saussure. As for Scotland, apart from Hume and Smith, we might mention the philosophers Hutcheson, Reid and Kames, the scientists Black, Watt, and Hutton, the novelist Smollett, the poet Burns, and the historian Robertson. Scotland was far more creative than England in this period, in sharp contrast to the preceding century.

"Diversity" @ Harvard, a reminder....   posted by Razib @ 11/19/2005 12:37:00 AM

I was checking to see which "similar pages" google popped up for this weblog, and found this article from Harvard Magazine, "Roots" and Race. We've tacked this issue before, but I though I'd pass on the interesting statistics dug up on this topic.

n = 170

Ethnic self-identification of Harvard black students

Black American, 57.1%
Afro-Caribbean, 21.2%
African, 13.6%
Bi-ethnic or biracial, 25.9%

Generational status, Black Harvard vs. US aggregates

1st generation, 8%, 6.1%
2nd generation, 41%, 3.3%
3rd generation, 6%, 0.9%
4th+ generation, 45%, 89.7%

Now, I don't much think about these topics anymore, science is much cleaner & exciting. Nevertheless, it is important to remind myself of why I'm a cynic sometimes. You can read the original paper too (note that 50% of the fathers of black Harvard freshmen have advanced degrees, diversity by race, but not SES).

Friday, November 18, 2005

Stumbling & bumbling   posted by Razib @ 11/18/2005 10:31:00 PM

I have noticed over the past few days that a lot of people are coming through Stumble Upon. I've used this in the past, and it is a neat service. And at this point, it is now the #1 source of new traffic to the site besides google and yahoo! I don't know if this will last, though the google boost in the fall of 2003 did stick. If you did come via Stumble Upon, welcome.

"Just your average Jewish genius[es]" in Israel   posted by Arcane @ 11/18/2005 06:33:00 PM

Hat tip: Captain Capitalism and The Economist

Addendum: As requested, The Economist print edition article from which this chart originated.

Superman Returns   posted by the @ 11/18/2005 12:06:00 PM

The Superman Returns teaser trailer is online. They made an interesting choice to play up the Christ allegory in the trailer. I like the score -- does anyone recognize it, or is it original?

Religion & evolution   posted by Razib @ 11/18/2005 10:00:00 AM

Are religion and evolution at eternal enmity? Well, I think the answer is is not as clear as we might assume. Below are the answers to three questions:

God: "I know God exists and I have no doubts about it"
Bible: "The Bible is the actual word of God and it is to be taken literally, word for word"
Evolution: "In your opinion, how true is this? ...Human beings developed from earlier species of animals"

Country, God, Bible, Evolution

USA, 62.8, 33.5, 35.4
N Ireland, 61.4, 32.7, 51.5
Philippines, 86.2, 53.7, 60.9
Ireland, 58.7, 24.9, 60.1
Poland, 66.3, 37.4, 35.4
Italy, 51.4, 27, 65.2
New Zealand, 29.3, 9.4, 66.3
Israel, 43, 26.7, 56.9
Norway, 20.1, 11.2, 65
Great Britain, 23.8, 7, 76.7
Netherlands, 24.7, 8.4, 58.6
W. Germany, 27.3, 12.5, 72.7
Russsia, 12.4, 9.9, 41.4
Slovenia, 21.9, 22.3, 60.7
Hungary, 30.1, 19.2, 62.8
E. Germany, 9.2, 7.5, 81.6

God:Evolution, -0.463
Bible:Evolution, -0.488
God:Bible, 0.93

Modest negative correlations in regards to evolution, though the number of data points isn't that high, so don't read too much into it. Interestingly, the only nation that resembles the USA is Poland. Ireland, which until recently was considered as traditionally Roman Catholic as Poland, is as evolutionarily oriented as most of the "secular" countries (i.e., closer to atheist "East Germany" than the USA). The decoupling with Poland suggests to me social factors at work, likely in Communist countries evolution was associated with the ideology of Marxist-Leninism (ironic in light of Lysenkoism, though of course even they accepted the fact of evolution, just not the orthodox process). Which brings me to Russia and the Philippines, on the one hand, Filipinos express more faith in God and the Bible than all of the other nations on the list, but this Roman Catholic country tends to accept evolutionary theory. On the other hand, 80 years of Communism have worn away the religious sensibilities of the Russian people, but they are highly skeptical of evolutionary theory. Contrast this to East Germany, just as secular, but positively predispoed toward evolution. Overall, one should be careful about wording, the evolution question seems pretty clear, but the other two have fudge room depending on how the languages weight things I suspect.

Other data points welcome.

Note, Correlations without the Philippines:
God:Evolution -0.58
Bible:Evolution -0.66
God:Bible 0.90

Without the USA:
God:Evolution, -0.39
Bible:Evolution, -0.44
God:Bible, 0.93

Addendum: Please note that the question was phrased in regards to the origin of humans. This is the sticking point in regards to evolution for many, the idea that humans and animals have some relationship is innately abhorrent. Or is it?

Many of you know I have an interest in the cognitive study of religion. There are certain gross features of religious expression that are universal. Belief in an anthropomorphized supernatural agent is one of them. Even in religions, like Islam, where God is a power of unfathomable majesty, or those like Buddhist which explicitly reject a Creator God, supernatural agents are referred to in very similar terms by everyday believers. You can take the religion out of supernatural agents, but you can't take supernatural agents out of the religion.

Those of us who live in the United States are somewhat skewed I think by the interaction we have with fundamentalist Protestants of a particular sort in assuming that by their nature religious individuals will reject an animal origin for our species. In part this is because fundamentalist Protestants make their objections most forcefully on these grounds. But I think if one looks at the long view of religious belief, there is no fundamental canalized bias toward rejecting an animal origin for humanity.1 I emphasize origin because there is clearly a bias to recognize that humans are somehow different, superior, but the relationship between man and beast is often far more intimate than acknowledged within fundamentalist Protestanism as it has manifested itself in the United States. We all know about Native American religious traditions which imply a kinship, and common origin, between various species and humans. We also are aware that Egyptians explicitly worshipped Gods in animal form. The Myrmidons of Achilles were derived from ants. In many Hindu religious traditions the boundary between man and animal is more diffused than in the Abrahamic creeds.

In short, there is no reason to a priori counterpose an acceptance of the animal origins of the human species (physically) with religion in the broad sense. Rather, it is a particular religious tradition which has born fruit in the United States and is now being exported throughout the world which rebels against this identification. To be frank, I suspect that some atheists who tightly couple their evolutionism with their anti-religionism (Richard Dawkins) have a difficult time in making the distinction between conservative Protestantism and religion in the broad sense.

1 - Remember that peoples are often liable to cast aspersions of bestial character on other nations, and, there have been confusions as to whether Great Apes are simply a form of "man."

Thursday, November 17, 2005

John in Slate   posted by Razib @ 11/17/2005 09:24:00 PM

John was mentioned in a Slate piece. Congratulations! Although recent forays into google finds Hawks invading much of the front page territory in relation to human evolution....

The new center   posted by Razib @ 11/17/2005 06:30:00 PM

Carl's new book, Smithsonian Intimate Guide to Human Origins, is out. In a post on the unveiling of the book, Carl concludes:

There's plenty of evidence that our species has continued to evolve in just the past few thousand years. At the same time, though, the rise of human culture, medicine, and genetic engineering may be sending our species off on an evolutionary trajectory that's impossible to predict....

YES!!! Human evolution continues. Over the past week I've become inordinately absorbed in the "Intelligent Design" "debate." As you can observe in the track of the past week's posts the topic has been sucking all the oxygen out of the air and edging other topics aside. There were a few posts that I had meant to get to this week that have been postponed. One of the worst attributes about the Intelligent Design debate is that it takes up finite time that could be devoted to the forwarding of science rather than having to shore up the base. The latter is a necessary task, and over the history of this weblog I have avoided the topic of Creationism and Intelligent Design and allowed Pharyngula and Panda's Thumb to lead the charge. Instead of debating whether evolution occurs (which, frankly, reasonable people can agree upon), the implications of evolution and its relation to our species seem a far more fascinating topic (and one avoided by many).

And yet the Intelligent Design/Creationism meme is like crack-cocaine, so bad and so good. One comment by "Alexandra" in response to John Derbyshire's response to my question on that topic triggered a blogstorm and spawned multiple posts (and frankly I had to restrain myself). And yet like masturbating to porn, after the fact I always wonder, "But couldn't I have done something better with my 10 minutes?" Frankly, IDers/Creationists don't play by the rules. Alexandra seemed to have been a rather sophisticated, if somewhat opaque, specimen. If you look at her last comment, she dismisses the whole enterprise of evolutionary population genetics (she seems to have problems with the infinite alleles model from what I can gather, but she's not the only one, and those who do reject that the widespread use of this model do not reject evolution). Now, I will assume she has read Kimura, nevertheless, her initial characterization of Fisher's Fundamental Theorem and the peculiar (unqualified or nuance) assertion about advantageous mutations and the scientific viewpoint of them does not suggest to me that she is treading on home ground. And yet she felt confident passing judgement on models which are the work of decades.

Many would characterize scientists as arrogant and self-absorbed. But one must remember that most working scientists devote a substantial proportion of their life to preparing for their research. They forgo many small pleasures so that they may attain fluency in their own disciplines. I am not a scientist, I am an observer, and I try to bring some humility in the enterprise of attempting to decode and interpret the theory and data that which are the fruit of lifetimes. I have gone on at length about the importance of having faith in the scientific system in progressing forward through the inevitable noise, so I will not elaborate on that point. But I think one reason that Intelligent Design and Creationism is so infuriating to working scientists is that it makes a mockery of their lives, of their enterprise. This attitude is found outside Creationist circles, see John Horgan's In Defense of Common Sense,1 for true arrogance on display.

The advocates of Intelligent Design and Creationism are challenging the scientific system, not presenting a new hypothesis. The fact is that for some the hypothesis of the Intelligent Designer and its dovetailing with theism is problematic. But I don't think that is the source of the rage and fury for most scientists and sympathizers with the scientific movement, rather, it is the attempt to suborn the system of science in the interests of a narrow and trivial concern. Especially in light of the fact that freeware like ClustalW and TreeView along with a few queries in BLAST can give you a gene phylogeny within 10 minutes which confirms the utility of the evolutionary paradigm. Some of you may object that the Intelligent Design hypothesis is not "narrow and trivial," but of deep interest and concern to the religious. One must be careful how one states this though, the reality is that the majority of religionists in the developed world, and the majority of religious clerics, do not subscribe to Intelligent Design. Are they not believers? My contention, roughly, is that the Creationism and Intelligent Design movement have no claim to being more authentic or true readings of the Christian faith. The situation we face in the United States is the consequence of contingent historical events. Specifically, it is a reaction to excessive modernism that swept through Protestant theology in the 19th century. Richard Dawkins has famously equated evolution with his atheism in The Blind Watchmaker, and certainly for many evolutionary theory is a gateway toward a paradigm which replaces their religious worldview. But not for all, and broadly speaking, many events and outlooks can trigger a shift from a religious to a post-religious view. There maybe be a non-trivial correlation, but I think we are looking down the wrong road if we see in Darwin the death of God.

Roughly speaking, the vast majority of those who would assent to the theses of Intelligent Design or Creationism are the types who will aver that "A is not A." This is maddening. No matter what losses are incurred, they are impervious to scientific rebuttal. The most frustrating aspect for me is the bad faith in which they argue, in that they will often ask disarmingly simple questions which demand complex, nuanced answers. Upon their satisfaction that their question has been answered, they will proceed to the next simple question! When I was using IRC in the mid-90s I idiotically spent 2 hours responding to a Creationist who would ask me, "Now answer me this: [insert canned question]." There was no hesitation or processing of any of my answers, if I wasn't stumped, she was prepared with her next question. In short, it is as if they are attempting to "run out the clock." Ultimately, they don't care about the results of the discourse, they know the truth, and they know you are in error. They are simply attempting to "catch you" in a mistake, or intimidate you. When I was often confronted by Creationist friends with the Second Law of Thermodynamics "disproof" of evolution, but could respond with a canned talking point (i.e, "Open system vs. Closed system"), they were absolutely unabashed and didn't push the argument. Upon further questioning I realized 1) they really didn't understand what "Thermodynamics" was, 2) they were just trying to intimidate me, 3) they were brushing up on other "gotchas" now that that one didn't work (fossil gaps, etc.). This is why the "they are just humble folk trying to make sense of the world" schtick doesn't ring true to me as apologia for anti-evolutionists, I knew them as a kid, and they weren't humble and naive, they knew very well what they were trying to do and what they believed, and they were willing to go to great lengths to validate their own self-worth and system of thought. They didn't care, or give thought to, what the cost of adding another notch in their faith-belt might have been.

But I didn't start out this post intending to talk much about Creationism. Rather, I wanted to point to Carl's contention about recent human evolution. We are certainly on the Bruce Lahn bandwagon, and to my mind that is the most spectacular and mind-blowing possibility of the power of selection. Nevertheless, when talking to people about human evolution, that's not where I start. I often meet individuals who are somewhat interested in science, but repeat to me assertions which imply that God or nature has stabilized humanity over the past 50,000 years. Being educated people, they have likely imbibed the Tooby-Cosmides dogma that evolution ceased after the Pleistocene, along with Lewontin's Fallacy. But there are easy ways to point out the salience of recent evolution, consider the spread of lactose tolerance. In Eurasia, this gene likely began to increase in frequency ~10,000 years ago with the domestication of cattle. The genetics implies that the Eurasian alleles probably have their origin geographically in Northern Europe, but a selective sweep has pushed the frequency of lactose tolerance as high as 70% as far as Northern India. It is a common assertion that humanity is no longer subject to selection because we reshape our environment to suit our biases, but the reality is that our affect on the environment is inducing a feedback loop so that the forces of selection are being modulated. The logic is not particularly difficult, and ultimately examples like lactose tolerance can convince the uninitiated rather easily.

This is why I would much rather aim at those who deny the importance of evolution in regards to humans today, though they accept evolution. This is not an "A is not A" situation, there is a common ground of reference which I can draw upon. The discourse is not always in good faith (i.e., a rejection of recent evolution is often characterized by progressively more implausible models whose selection seems ideologically driven), but I can conceive of the other individual's general cognitive architecture, so it is far easier to pinpoint and leverage weak points in the design. Instead of focusing on pointless and purposeless intellectual guerrilla wars against an enemy which knows no code of honor and is willing to take civilians hostage, it is far more pleasurable to conquer new territory, even if the enemy has the commanding heights. The strategy in this case is simple, war by attrition and artillery. Better a bloody inch than another wound as you sink into the mire and lose sight of the blue sky above.

Addendum: If you are curious about the Intelligent Design movement, I recommend you check out The Access Research Network, The International Society for Complexity, Information and Design and William Dembski's weblog Uncommon Descent. Some readers might find H. Allen Orr's smackdown of Dembski of interest. Unlike some, I don't think that Michael Behe, author of Darwin's Black Box, is really the front & center intellectual in the ID movement. Though somewhat delusional2, Behe seems sincere enough. On the other hand, Dembski plays the wizard, trying to obfuscate with mathematics.

1 - One of the biggest problems I have with Horgan's manifesto is that it seems to totally ignore that the reality that science is not a hereditary institution. If he was really curious about the topics and wanted to transcend common sense, all he needs are some books and some teachers.

2 - From page 232 of his book: "The result of these cumulative efforts to investigate the cell-to investigate life at the molecular level-is a loud, clear, piercing cry of "design!" The result is so unambiguous and so significant that it must be ranked as one of the greatest achievements in the history of science. The discovery rivals those of Newton and Einstein, Lavoisier and Schrodinger, Pasteur, and Darwin."

Heterozygosity and vigor   posted by Razib @ 11/17/2005 08:45:00 AM

An interesting paper is out in PNAS titled Genetic diversity and reproductive success in Mandrills. The money shot:

We found that heterozygous individuals showed greater reproductive success, with both females and males producing more offspring. However, heterozygosity influenced reproductive success only in dominant males, not in subordinates. Neither the acquisition of alpha status in males, nor social rank in females, was significantly correlated with heterozygosity, although more heterozygous alpha males showed longer tenure than homozygous ones. We also tested whether the benefits of greater genetic diversity were due mainly to a genome-wide effect of inbreeding depression or to heterosis at one or a few loci. Multilocus effects best explained the correlation between heterozygosity and reproductive success and tenure, indicating the occurrence of inbreeding depression in this mandrill colony.

Inbreeding depression often occurs when recessive and or deleterious alleles are unmasked in the genome. Well all carry a mutational load, and I have read/heard that each human harbors 3 de novo unique lethal mutations. The importance of outbreeding is that it perpetuates complementation so that a good copy is present to compensate for the faulty copy of a given gene. The logic is crystal clear as to why brother-sister matings are extremely deleterious: they are likely to share bad copies from their parents, so complementation will not occur and the lethal or deleterious alleles will be unmasked. For example, if a lethal copy of a gene is present at a frequency of 0.1% in the population, it would be unmasked due to random mating at a rate of 1 in 1,000,000 (0.1%*0.1% = 0.001*0.001, va p2 + 2pq + q2 = 1). If parents are heterozygous for that same lethal copy (that is, both carry a good copy as well as the bad copy), simple Punnet Square logic tells us that 25% of the offspring are dead on arrival. If you constrain the breeding population to descendents of this pair, the initial generations will have a high mortality rate because of the reexpression of the lethal copies. Obviously selection will work against it, but in a small population random genetic drift is strong enough to fix even deleterious alleles! If it was a lethal, you get population extinction, but that is not the only scenario. One could have mildly deleterious alleles scattered across the genome, for which fixation and reproduction of this state during subsequent generations are both possible.1 These loci would be a non-trivial fitness hit, but they would not be the kiss of reproductive death. The implication above is heterozygosity, the tendency to possess two versions of the same gene on a locus, as opposed to the same version (homozygosity), tends to correlate well with a low expression of negative mutational load (due to cumulative masking effects across many loci). On the other hand, the researchers point to no evidence of heterosis, which would imply that the heterozygote phenotype was more fit than either homozygote alternatives. This is not surprising, it is relatively hard to find this in nature (over the long term this might be true of the MHC loci, though the line between that and frequency dependent selection is fine in my opinion).

A mandrill colony is interesting because they are primates, our cousins. Biology is a science of generalizations with many exceptions because the species sample space is so large, and looking toward complex mammals, and primates no less, can give us insights into humans (though they are not determinative or definitive! Monkeys we not be). Steve points me to this piece which offers that:

...British Pakistanis account for 30% of all British children with recessive disorders, which include cystic fibrosis.

Why? See here:

The research, conducted by the BBC and broadcast to a shocked nation on Tuesday, found that at least 55% of the community was married to a first cousin.

I have elucidated the prediction equations in regards to recessive diseases and cousin matins before. Though the individual risk may be low in absolute terms (i.e., 2% vs. 0.1%), the social impact of cousin matings can be great as the frequency of many diseases can jump by orders of magnitude. Additionally, as I noted previously, many Westerners neglect that the coefficient of inbreeding of one's ancestors must also be a consideration, so highly inbreed clans who have engaged in successive generations of cousin marriage may exhibit more inbreeding depression than one would expect based on paper registrations of "first cousin" relationship because of random genetic drift within the extended family.2 I am skeptical than in the British Pakistani community reproductive skew is strong enough to purge the genetic load from the population...perhaps there is no reason to fear the demographic impact of Muslims?

1 - See Muller's Ratchet.

2 - If two first cousins mate, the coefficient of relatedness is 1/8. But, that assumes that the grandparents are unrelated. What if both of grandparents are first cousins? And the parents are first cousins? I leave it to you to draw the pedigree.

Wednesday, November 16, 2005

Peregrinations   posted by Razib @ 11/16/2005 09:48:00 PM

We are shifting around bloghosts a lot this week. If you have problems accessing GNXP, don't worry, everything will be stabilized by early next week. Since we use blogger now, you shouldn't miss any posts, and I will be posting as if nothing is happening. But, expect another IP switch this weekend, which means some of you will be out of synch for perhaps 12-24 hours. Anyway, just a heads up.

Update: Lei mentioned she didn't have my email address. Please note, it is contactgnxp ---at--- Also, if you forget it or don't have it, and the site is down or suspended, check the google cache and click the 'contact' link and the javascript alert should work fine that displays the address.

Tuesday, November 15, 2005

An "honest" question   posted by Razib @ 11/15/2005 09:09:00 AM

My correspondent follows up:

As a scientist, how can you refute the design hypothesis? I am assuming you don’t support the presence of this theory in public schools. I know it has virtually zero scientific backing, but isn’t it important to present as a belief, at least so our youth can reject it?

It just seems shameful to me that so many scientists refuse to present a theory, lack of scientific backing and all. I consider myself an anti-theist and would love this theory presented in public schools, as opposed to denying that the theory even exists.

As I said, there are many hypotheses that are irrefutable. I think the design one is (so is the idea we are simulations in a computer of incredible power). Anyone who has even mildly looked into the topic knows that this is a serious problem.

There goes 5 minutes of my life.

Is Natural Selection a Tautology?   posted by DavidB @ 11/15/2005 03:54:00 AM

This question was raised in some recent comments, and I want to discuss it more fully than was appropriate to a comments box.

In population genetics, fitness is usually defined by reference to reproductive success. The details vary - some authors define fitness by the absolute number of offspring, some by reference to the population average, and so on - but roughly speaking, the fittest organism (or gene) is the one with the greatest number of offspring. It may therefore be said that the ‘reproduction of the fittest’ is a tautology: the fittest individuals necessarily have the most offspring, because that is how fitness is defined.

This is apparently regarded by Creationists as some kind of knockout blow for the theory of evolution by natural selection. Oddly enough, they also argue that natural selection is inadequate, impossible, and so on, which would be absurd if they really believed it was a tautology. No-one (except the late Willard van Orman Quine) spends much time arguing whether all bachelors are unmarried.

But the point I want to emphasise is that even if we define fitness by reference to reproductive success (which is convenient, but not essential, in population genetics), this in no way implies that the theory of evolution by natural selection (TENS) is a tautology.

TENS involves at least the following seven empirical facts or generalisations:

1. Individual organisms differ in reproductive success. This is not a tautology: it is an empirical matter of fact. It would logically be quite possible for organisms all to reproduce equally (or to live for ever without reproducing, like angels - though Genesis 6: 2-4 may cast some doubt on the last point).

2. Differences in reproductive success are associated with phenotypic traits. Traits associated with superior reproductive success (in a given environment, etc.) may be described as adaptive. It is not a tautology that adaptive traits exist. It would be logically possible that differences in reproductive success are merely a matter of chance. In this case there would be no way of predicting whether a trait would increase in frequency from one generation to the next. After a succession of many generations, purely by chance, some traits might increase or decrease in frequency, but this would be genetic drift, not natural selection. Probably a great many genes, and some phenotypic traits, have increased in frequency by genetic drift, but TENS maintains that adaptive traits are usually due to natural selection. (By chance, drift may also sometimes promote an adaptive trait, but this is unlikely to be important except in small populations.)

3. Some adaptive traits are heritable. They tend to be reproduced by genetic inheritance, even over many generations. This is not a tautology. It would be logically possible that offspring did not share their parents’ adaptive traits, or that these would disappear after a few generations. One of the objections Darwin himself had to face was that favourable traits would be ‘washed out’ quickly by interbreeding. Darwin had no conclusive answer to this, but modern genetics has shown that genetic material is very durable, and not destroyed or ‘blended’ by interbreeding.

4. From time to time there are variations (mutations, in a broad sense), in genetic material. This is not a tautology.

5. Some mutations increase adaptiveness. This is not a tautology.

6. There is no inbuilt limit to the amount of cumulative genetic change. This is not a tautology.

7. Perhaps most important of all, mutations have no tendency to occur in directions favourable to adaptive traits. It is often said (and I have recently said it myself) that mutation is random with respect to adaptativeness, but this can be misleading. It is highly likely that the majority of mutations reduce adaptiveness, as there are more ways of reducing it than increasing it. But a minority of mutations increase it, and these are the ones that are favoured by natural selection. This is not a tautology. It would be logically possible that mutations occur preferentially in adaptive directions. Many non-Darwinian theories - Lamarckism, orthogenesis, ‘directed mutation’ of all kinds - have maintained that this actually happens. If this were true, TENS would either be false or reduced in importance. Indeed, there have recently been claims that in some circumstances directed mutation does occur. It remains to be seen whether this is confirmed, and if so whether it is really important or just another minor ‘tweak’ to evolutionary theory.

I conclude that while population genetics may contain some tautological statements (as John Maynard Smith once remarked, any theory involving two lines of algebra will contain tautologies), the theory of evolution by natural selection is by no means a tautology, and rumours of its death are, as usual, greatly exaggerated.

Monday, November 14, 2005

"Among Orangutans: Red Apes and the Rise of Human Culture"   posted by Theresa @ 11/14/2005 10:39:00 PM

Short but interesting interview with Carel van Schaik (orangutan researcher) in the NYT:
Q. So your discovery that the orangutans learned tool use from one another explains "the rise of human culture" part of your book's subtitle?

A. Well, yes. Orangutans split off from the African lineage some 14 million years ago. If both chimps and orangutans make tools, our common great ape ancestor probably had the capacity for culture.

I, atheist   posted by Razib @ 11/14/2005 08:36:00 PM

I received this email from a reader:

First, I find your blog interesting at the very least.

You seem to know your stuff, and I need a question answered regarding atheism, a quasi-religion (in my mind) that I am assuming you subscribe to follow. It is as follows:

How can an atheist reject religion based on the fact that it has no scientific backing? Doesn't the belief that there is, in fact, no God subscribe to the same non-science dogma. I would think a scientist would welcome any possible hypothesis for, say, the beginning of life...even design.

Please explain.


My atheism is a given that suffuses my perspective on this weblog. I don't talk about in much detail, but below is the transcript of my response to this individual's questions.

1) Atheism as a religion depends on how you define religion.

2) Also, Jains and some forms of Hinduism are explicitly atheistic. If you didn't know that, well, you should do some more research. I certainly am not a Jain or a Hindu, but am an atheist. In short, atheism is simply a contention relating to a specific hypothesis, the theist God, nothing more, nothing less.

4) Atheists can reject a specific God hypothesis on scientific grounds. i.e., some Hindus believe that Sai Baba is God. Atheists can stipulate that God meets definitions a, b, c...and see if Sai Baba meets those conditions. If he does not, you reject the Sai Baba God hypothesis (the emperor Domitian also declared he was a living God, I believe he was incorrect, I am an atheist in regards to the Domitian God hypothesis).

5) Atheists can reject God on philosophical grounds. i.e., that the definition of God is incoherent. For example, the old standard that a theist God is omniscient, omnibenevolent and omnipotent and the problem of evil. If evil exists, such a God can not by definition exist, and so on (if he is good and has power to generate good at will, then he should abolish evil, because he can). My understanding is that some theologians get around this issue by contending that evil in this world is not due to God, because of free will, or that evil is the lack of good (a negation rather than a positive trait), so God did not create evil. In my opinion this is word-play or sophistry (free will has been a dispute within Christianity since St. Augustine, with no real resolution that I can see).
I find philosophical dodges of this sort unconvincing, nort do I find the "proofs" in Summa Theologia, or by latter day thinkers like Norman Malcolm or Richard Swinburne, plausible.

6) There is a long dispute in online atheist circles about distinctions within atheism, negative atheism (lack of belief in God) vs. positive atheism (belief that God does not exist). Ultimately, they are word games to the first approximation. I would say that:

a) on a subset of God hypotheses are I am an atheist for scientific reasons. Rambling God-men seem not to be any sort of God that I can understand, they are outside the parameters of my God definition, i.e., I am a positive atheist in regards to them.

b) on a subset of God hypotheses I am an atheist for philosophical reasons. There are logical incoherencies in the traditional monotheistic God concept which must be resolved by "faith" or "mystery." Viewed in the context of logic supplemented by empirical observation ( i.e., Jesus did not return with the passing of the generation) I conclude the probability value of this God existing is trivial, and likely impossible assuming some premises. On the other hand, anything is possible if faith and mystery are on the table, but that is a different issue.

c) on some Gods I am a negative atheist, in that I do not reject their existence, but I presume they do not exist because I see no reason for their existence. This is the "invisible pink unicorn" idea, there are no logical or scientific grounds where I can really falsify this construct, but I really don't believe in it without further evidence. Some of the ideas of God promoted by liberal theologians are certainly in this ball park, I have a difficult time trying to understand what sort of God Marcus Borg is talking about, so it is really difficult to conclude if I am an atheist toward his panentheism (that is not a typo, I do not mean pantheism, panentheism is really different, trust me, or trust Borg).

d) some Gods I do believe in due to semantic issues. Some have told me that God is love. Well, I believe in love.

If you have further questions, I refer to you to the Atheism Web:

This isn't rocket science :)

One thing I will add, which isn't in the email, is that the implication of what I have said above is that depending how you define atheism, it is somewhat orthogonal to beliefs about Intelligent Design. After all, the Designer doesn't have to be God! (*wink*) Also, some atheists are naked as babies when it comes to Christian apologetics or familiarity with the scriptures and theology of that religion. I am not one of those atheists, regular readers can glean that, my lack of belief is not likely due to ignorance of the major world religions. I only add that because some have asked on this blog whether I have even considered the possibility that God might exist, I would ask that people who pose this question go read Summa, Norman Malcolm and Richard Swinburne, before implying that I might not have explored the possibilities of the Way of Reason.

Finally, it seems to me that the primary reason people believe in God is not because of reason, though they will often give teleological or cosmological explanations (i.e., "believe there are trees and birds, they must have been designed"). I think there are particular cognitive biases that humans have that predispose us to acceptance of the reality of supernatural agents. I suspect that a wide range of variables canalize the development of the human mind so that in social groups a modal acceptance of supernatural agents is nearly universal, that is, all human cultures seem to believe in God-beings. This contention is wholly separate from disputes around the theistic God of the philosophers. I do not believe that the God that people have in their minds is the Ultimate Ground of Being of Tillich or the Brahma of Hinduism or the Trinitarian entity of traditional Christianity, rather, they are more prosaic supernatural agents which are individuals, persons, with traits and characters that render them above humanity (a mix of conventionality with counterintuitive powers). In terms of why I am an atheist in regards to the broad sense of supernatural agents, I suspect that the primary reason is frankly innate. Not that I don't have a God module, I don't think that there is such a thing, I suspect I do not exhibit the conformation of traits and characteristics which result in a biase toward God belief. In other words, if you have a normal distribution of "God belief," with a few hypermystics and fanatics, with a majority of mild believers, you will also always have those who are simpy not predisposed to believing in supernatural agents. There are some people who reject God for deeply personal or philosophical reasons (Dan Barker comes to mind), but I think these are a minority whose prominence is assured only by their participation in atheist organizations. Similarly, there are people who believe in God simply because of social, cultural and personal reasons, though if they reflected upon it they would likely acknowledge that their own belief was a tepid and rote affair in comparison to most people in the pews.

Hobbits and humans and giants ... oh my!   posted by Theresa @ 11/14/2005 04:00:00 PM

Giant ape lived alongside humans

A gigantic ape, measuring about 10 feet tall and weighing up to 1,200 pounds, co-existed alongside humans, a geochronologist at McMaster University has discovered.

Using a high-precision absolute-dating method (techniques involving electron spin resonance and uranium series), Jack Rink, associate professor of geography and earth sciences at McMaster, has determined that Gigantopithecus blackii, the largest primate that ever lived, roamed southeast Asia for nearly a million years before the species died out 100,000 years ago. This was known as the Pleistocene period, by which time humans had already existed for a million years.

"A missing piece of the puzzle has always focused on pin-pointing when Gigantopithecus existed," explains Rink. "This is a primate that co-existed with humans at a time when humans were undergoing a major evolutionary change. Guangxi province in southern China, where the Gigantopithecus fossils were found, is the same region where some believe the modern human race originated."

I'm a fan (always have been since her stint on SNL)   posted by Razib @ 11/14/2005 03:07:00 PM

Profile of Sarah Silverman.

The bounds of discourse   posted by Razib @ 11/14/2005 11:58:00 AM

This an expansion on the post below. What is the problem when individuals like Alexandra pose their questions and critiques? You see the problem before you, I'm taking time out to talk about meta-science rather than real science. Time and resources are scarce. Alexandra threw out some contentions related to Fisher's Fundamental Theorem of Natural Selection. From what I can gather, she seems to be curious as how to evolution dependent upon variation (adaptation) can occur when natural selection exhausts that variation. Godless addressed many of the confusions due to the Theorem previously, and it is illustrative that the answers were directed at a very different perspective (i.e., the salience of evolution in regards to human beings). The key is that evolutionary biology is not fixed in 1930, and the relevance of Fisher's idea is disputed within the field. I am personally of the opinion that it is a good starting point, but that evolutionary biology will never be amenable to reduction into a deterministic science with an Ideal Gas Law analogy as Fisher would have liked. Mutation, migration and random genetic drift, as well as the reality that "fitness is a bugger," play important roles in modulating response to selection in a Fisherian context. I suspect Sewall Wright was right, in any reasonable time frame the landscape is often rugged. I'm being short, terse and unspecific because time is finite, and I'm peeved at having to offer this apologia when it would behoove anyone genuinely interested in the topic to read Jim Crow's Perspective: Here's to Fisher, additive genetic variance, and the fundamental theorem of natural selection (Crow is more positive than most in field of evolutionary genetics toward the Fundamental Theorem from what I can gather, including one of Crow's former post-docs who I am acquainted with).

Or look at this assertion:

Some scientists make the common mistake of assuming that all advantageous mutations are successfully incorporated into evolution.. In reality, almost all advantageous mutations are eliminated by genetic drift and play no role in evolution.

"Some scientists?" How to evaluate the impact of a qualitative assertion. Were there surveys done? Do physicists count in terms of their opinions as regards natural selection? As for the last assertion, it seems a garbling of the Neutral Theory debate. The probability of fixation of a mutation is 2s, where s is the selection coefficient, all things being equal. The probablity of a fixation of a neutral allele is 1/(2Ne), Ne being the effective breeding population. The relative power of selection vs. random genetic drift is a function of the relationship to each to effective population size, the larger the population, the more relative power selection has as generation-to-generation sampling error due to random genetic drift is reduced, the smaller the population and the noise from random genetic drift is liable to swamp out selection. Given a small enough population, even deleterious alleles can be fixed (for example, in inbreeding that occurs in a population due to its extremely small size, even if breeding is random). Motoo Kimura's insight via Neutral Theory is that most substitutions, that is, replacement of one allele for another in a fixed state, might not be due to positive selection, but rather neutral fixation. That does not imply that selection is irrelevant, rather, its power might be constrained to particular loci and regions of the genome. Assuming that the vast majority of the time the selection coefficient is less than 10%, well, by definition the majority of favorable mutations would not be fixed. This is naked algebra (and probability distributions), not a great mystery.

I am eliding over the issues relating to the character of the genome (psuedogenes vs, functional sequences vs. introns, etc. etc.), epistasis, frequency dependent selection, heterozygote advantage, variation of fitness over time and space, and the general shiftiness of fitness in a host of contexts. There are many books have been written about this topic, and whole careers have been devoted to it. And yet here we have Alexandra ambling on in and presenting her talking points as if they are important and we should address them. It is rather frustrating. I am skeptical that she was in good faith examining evolutionary genetics and asking us for pointers to the literature, she was telling us how things really were, as if the secondary and tertiary information she recieved was the last word. You ask Alexandra why I insult you instead of engaging you, the broader problem is I wish you would engage the extent literature before you waste, yes, waste, my time. Someone with your intelligence could assimilate the information in Evolutionary Genetics, and so obviate the need for me to respond to your queries. More importantly, the basic concepts and their analytic elucidation take time and effort, and you can not assume that the questions you ask in 1-4 sentence formats really have 1-4 sentence responses, they do not. There are many parameters in these models, and each parameter is scaffolded by qualifications and conditionalities. For every minute of your time spent asking, there goes 15-30 minutes of my time responding. This doesn't seem fair to me. From your prespective I am sure it seems rude of me to insult you, but I have spent many hours studying population genetics and evolution, and it is an insult to the work I have put in to knowing this area to see that you expect that I should respond in a timely fashion to what seems to me like an uninformed query. To ask good questions in science one must already know many answers.

One problem I have with this issue in regards to Creationism is that I am skeptical that most non-evolutionary biologists, let alone a lay person, would know about Fisher's Fundamental Theorem. No matter the reality that evolutionary biologists on the whole don't see the theorem as explanatory in a general sense, use of "technical terms" like Fisher's Fundamental Theorem of Natural Selection seems to me a question of style and bluster rather than substance. I've seen this before, the use of the Second Law of Thermodynamics to disprove evolution. Today, we see it in irreducible complexity and no free lunch theorems. I think this sort of tactic is shit, it undermines our trust and value of genuine technical knowledge by its obfuscation through use in ideologically driven models. All science is to some extent politicized, but instead of being part & parcel of the method and dynamic of the scientific ecology, these tactics are more likely to yank the keystone species (trust) out of the network and send the system crashing. Creationists and Intelligent Design folk complain they don't get funding, well, I just heard that a recent NSF grant panel approved funding for 10% of the applications in the area of evolution and ecology, so don't come crying. If Creationists and Intelligent Design people want money from the government, they should find a way to make it relevant to human health so that they can tap the NIH money train.

Moving from this specific case to the general point, there is the persistent problem of how to judge the veracity of one's comments if one does not have specialized knowledge in a given field. Again, this is a topic of wide berth. Those of you who read this blog know that I try to be a "shit filter." If I don't know about a topic, but feel I should, I try to read some monographs. Being a non-specialist, and having finite time, I don't get far, but I try to make the best of it. Sampling error is going to be high, I'm only going to read a max of a dozen books on a topic, and a dozen papers. Nevertheless, I also try to take the temperature of the field and try to impart to readers of this blog what I perceive to be the dominant paradigm. I don't expect readers to be the same, time is finite and we allocate it according to our personal preferences and utility functions. Most readers of this blog are pretty intelligent, and I suspect they are used to being able to bluster and bullshit their way through everday discourse, but remember, that shit don't fly here homey, do your fucking homework. Don't repeat pointless cliches in language that connotes erudition, I am good at picking out historical errors and evolutionary mistakes, and there are dozens of readers here with specializations deep enough that they can pick you apart if you don't have your shit together (I know, it happens too frequently to me when I post). It's a good thing when you can admit you are wrong, a bad thing is being stubborn and refusing to accept the judgement that you overextended yourself and aren't in the same comfortable intellectual milieu where everyone agrees with you, or, where everyone is less intelligent than you.

Who judges what? That is the question. Here, I'm the final judge. I sure make a lot of mistakes, but the end, you're going to have to have faith. If you don't like the rules, no one is forcing you to play, and you certainly aren't invested in anything aside from a few minutes of your day (your investment is far less than the time and energy I've put into this weblog over the years).

Time is finite, and there goes 30 minutes.

Sunday, November 13, 2005

More than meets the Census worker's eye   posted by Razib @ 11/13/2005 11:19:00 PM

Earlier this year in Genetic structure, self-identified race/ethnicity, and confounding in case-control association studies the authors found a very tight correlation between reported racial ancestry and separable genetic clusters derived from data drawn from many microstatellites. Importantly, though the Chinese and Japanese in the "Asian" cluster were separable, there was little evidence of further substructure within the other racial populations, but they offered caution in regards to the Hispanic group, which is clearly admixed. So, no surprise that Population stratification confounds genetic association studies among Latinos. They conclude, "Our findings suggest that empirical assessment of the effects of stratification is critical to appropriately interpret the results of case-control studies in admixed populations."

Saturday, November 12, 2005

Evolution, Dover, Kansas   posted by Razib @ 11/12/2005 11:29:00 AM

Linda Seebach quotes me in her column, One step forward, one back in the struggle against 'design'. If you recall, Linda commented on the Ashkenazi IQ affair last spring.

Friday, November 11, 2005

Asian American Demographics   posted by Razib @ 11/11/2005 11:29:00 PM

Googling the web I stumbled on to this nice little site on Asian American demographics (for some bizarre reason they add "Russians" to this list). There isn't a whole lot there, but it is nice layout for the Census data they are presenting. On a mildly related note, no surprise, George Barna finds that Asian Americans are the least religious of American ethno-racial groups while black Americans are the most (in the context of a wider survey). From the text:

...In fact, there was only one measure for which a majority of Asians exhibited commitment: 52% said their religious faith is very important to them, lagging the 68% among whites, 72% among Hispanics, and 89% among African-Americans.

No big surprise.

Never be so stupid   posted by Razib @ 11/11/2005 10:52:00 PM

Well, see this comment. I'm an atheist, but I'll pray for Derb if this is the caliber of gibberish that he gets whenever he posts about evolution. If you are as wilfully ignorant as this individual, never read this weblog again, you make me ill (OK, lightheaded with disgust). If you (dear readers) think putting this on the front page is unseemly, never read this weblog again, I have little patience for people lecturing me on how to run my weblog. I can't believe that standard Creationist tracts are debunking Fisher's Fundamental Theorem of Natural Selection, this has to be coming out of a quasi-intellectual Intelligent Design publication, but I don't know which. Just one more reason to be a believer. It is often said the more you know, the more you know how little you know. The converse is certainly true, the less you know, the less you know how little you know. Thank Sophia that Eugenie Scott, Michael Ruse and Ken Miller bear the cross of having to preach to the pagans in the dark heathen demon haunted lands. To tear believers from the contemplation of Truth is a vile thing that the heathens do with their falsehoods....

Update: I looked again at the comment again, and I couldn't help but wonder if the individual wasn't foreign. The second comment is really incoherent, it looks like it was produced by a really shitty AI that's still trying to learn English. Well, when I traced the IP, it was an AOL account (no offense to those of you with AOL accounts who are regular readers or friends, there can be virtuous pagans in heaven, never fear). So that explains it....

Update II: Alexandra has responded. Says:

I don't feel a need to defend my IQ....I will share that we have graduates of Brown, Julliard, Harvard, Purdue and Oberlin in my immediate family. I will also share that I send my children to a college prep Christian Academy who teach both ID and evolution and most of their graduates are not harmed by exposure to ID......they are accepted even at Yale.

You have nothing to fear from us.......but the way you have talked about me, people would think I have some contangeous disease and somehow just got off the boat from some 3rd world country.
It is important to note that intelligence is a necessary, but it is not sufficient, condition, to banish ignorance. Alexandra is clearly not familiar with the literature in evolutionary genetics, and is propogating patently false assertions when she contends that "most biologists believe that advantageous mutations become fixed" (it depends on how advantageous, most biologists would not assent to such an unqualified statement). The problem on this weblog tends to be that people spout off on things they don't know about (i.e., making a very weak analogy between historical and ecological processes and not willing to concede that that analogy was weak), not that they don't have innate intelligence. Smart people can be stupid, and in fact, they are stupid in a more verbally impressive and coherent fashion than the innately dumb. To speak specifically to Alexandra, would you trust the conclusions of a Harvard physicist as to the character and historical validity of the Bible if he had only read snips and a small number of exegetes? That is very close to what most advocates of Intelligent Design engage in, you know a few critiques very well, but the whole forest is a deep dark mystery.

As for whether Alexandra and her ilk have a disease, to some extent, yes, they do. The disease threatens the intellectual edifice that the West has created over the past two centuries which I percieve to be singular in the history of our species. The threat is minimal now, but if realized, the implications are catastrophic. I am currently satisfied with the rebuttals put forth by the missionary monks I pointed to above, but it seems that each iteration of the counter-meme is getting stronger and stronger. More later.

Flu, evolution and Ewald   posted by Razib @ 11/11/2005 06:24:00 PM

John Hawks has a nice post up summarizing the debate that Paul Ewald has been getting into in regards to avian flu. It seems to me John leans a bit toward Ewald's position, and that is where I also come down. As we have noted on this weblog, the downstream consequences of an avian flu "pandemic" are likely to be negative and significant no matter the biological probabilities. But, I also tend to suspect that the "public health experts" are not as knowledgeable about the evolutionary big picture as the public might think (actually, I doubt the public is much aware of the evolutionary issues implied), and, there is some overreaction going on to take into account the worst-case-scenario, as opposed to the expectation. And you can't discount the influence that personal interests (jobs, research money, etc.) might have on the opinion of experts who really aren't that expert in the first place.

Population genetics notes   posted by Razib @ 11/11/2005 12:14:00 AM

Check out the class notes (HTML & PDF) on population genetics here! If you want to know why only 1 migrant per generation between populations of any size can prevent divergence in allelic frequencies, please read this.

Thursday, November 10, 2005

France   posted by Razib @ 11/10/2005 11:00:00 PM

Diana says:

There's nothing wrong with the French model of assimilation. It's worked beautifully with a variety of previous emigrants, which included Arab Muslims and Iranians. The problem is the NUMBERS. You can't assimilate huge amounts of people who speak a different language and worship a different God, especially Allah, a very masculine warrior sky-god. Something's got to give. A society is as fragile as an ecosystem. France will survive...but it is suffering a terrible case of indigestion.

I've been thinking of the ecosystem model lately. I have little else to say...for now.

...may I say....   posted by Razib @ 11/10/2005 06:35:00 PM

Statements like this, "I'd like to say to the good citizens of Dover: if there is a disaster in your area, don't turn to God, you just rejected Him from your city" (i.e., voted the Dover pro-ID school board out) make it a lot harder sometimes to enthusiastically reject the facile equivalence between Christian conservative nuttiness and Islamic conservative nuttiness. Robertson isn't encouraging people to bomb abortion clinics, but he obviously does live in a different cognitive world. Sometimes I wonder if the only chapter of the New Testament he has read is Revelation, but then I remember that he is a Pentecostal, so readin', writin' and 'rithmetic go out the door when the Holy Ghost comes a callin'.

(a)Sex scandal   posted by Razib @ 11/10/2005 04:19:00 PM

Bdelloid rotifers have been called an asexual scandal because they are long-lived (30-40 million years) lineage which does not make recourse to sex. The fact is that asexuality and clonal lineages litter the tree of life, but they are invariably lineages with little time depth. In other words, asexuality is often a recently derived character (from an ancestrally sexual state) across a taxon where there are a mix of sexual and asexual lineages. One could hypothesize that asexuality is a recent fad. This seems implausible. Rather, the conventional explanation is that asexuality in complex organisms results in a tradeoff, in exchange for a short term benefit there is a long term increase in the risk of lineage extinction.

Imagine a group of organisms which exhibit a variation in fitness. Even if a trait is 100% heritable, and perfect assortative mating results in trait matching, there is a strong possibility the favorable genetic combinations of the parents will be destroyed by Mendelian segregation (as alternative perfect combinations are broken up and scrambled together in the next generation in a more disharmonious fashion). On a population genetic level alleles which are coinherited together because of physical linkage on a particular chromosome also tend to be dispersed (toward linkage equilibrium) by recombination. Now imagine that one of these hyperfit individuals mutates and develops the ability to reproduce asexually (one assumes this would be a "female"). Voila, no more dilution of its advantageous genotype. Assume that the mutation that flipped the organism to asexuality was on one particular locus, call it Sex-. Because Sex- has packaged itself into a nice suite of genes and traits, it will start to outcompete Sex+ (i.e., the form of the gene which confers sexuality). Additionally, all the genes within the asexual individual are now being passed at a 100% rate to the next generation, instead of a 50% rate. Remember, your children are 1/2 of you genetically, clones are 100% of you. A mutation that confers clonality should spread like wildfire.

All is well. But the problem is that fitness is quite often not some intrinsic tendency, in other words, it is not necessarily an essential characteristic. A mutation that screams "abort me" and autodestructs is obviously intrinsically unfit, but we are talking about more subtle differences. Fitness is often a relative state, that is, the difference between an individual organism (or locus) and the mean population. It can vary a great deal as a function of time, environmental context and the dynamical state of the population within which the individual is embedded (both intra and interspecies). The problem with the Sex- locus is that it has fixed itself into a particular stable strategy that it won't be able to snap out of, barring mutation. In the short run there might be riches, but in the long run it will likely be overtaken by the changes in the world around it. And I haven't even gotten into explicitly genetic issues like Muller's Ratchet.

10 questions for Derb   posted by Razib @ 11/10/2005 08:29:00 AM

Recently John Derbyshire was kind enough to answer a few questions I posed for him. You all know John, so I'll introduce him with a quote from a commentor at John Holbo & Belle Waring's weblog:

Like him or not, John Derbyshire is one of the smartest people writing for NRO (Brookhiser may be comparable). For another example, Derbyshire is typically the voice of sweet reason itself when natural selection vs. creationism is at issue. It would be nice if all one's ideological opponents were as newborn-baby-dumb as [another conservative pundit]....

1) Over the past year you've really been hammering intelligent design. As someone who works in conservative journalism, that seems peculiar. I know in your famous/infamous "Metrocon" column you offered that no one at NR rejects evolution, but I am curious as to your motivation for devoting considerable space to this topic of late. What has the for:against ratio in your emails/letters been?

My motivation, so far as I am aware, is my lifelong fascination with science, the extreme scientific shoddiness of the I.D. movement, and my indignation that the I.D. people should presume to claim a place at the science table, when they don't deserve one. The main reason they don't deserve one is that THEY DON'T DO ANY SCIENCE. When I said this to Bruce Chapman, head of the Discovery Institute, at a meeting with him and some I.D. honchos, he said: "Oh yes we do!" and passed me a paper. Here is the paper.

Read it for yourself. I rest my case. The Discovery Institute has been in business since 1991, the CSC (its most currently active offshoot) since 1996. That's an aggregate 23 years, and this is all the "science" they have to show -- or at any rate, this is a star paper that the HMFIC likes to carry around to hand to people who accuse him of not doing any science. What a bunch of frauds.

Of course, if you press this point, the I.D. people say: "Oh, you know, our people just can't get their stuff published in the science journals because of prejudice." To which the response should be: "So you have abig pile of scientific results written up over there at the Institute, that you haven't been able to get published? Mind if I take a look through them?"

I know some young scientists. They have to waste half their time playing politics, angling for NIH grants, filling out forms. For all that, they are mostly poor, the grants mostly very niggardly, academic salaries lousy. If they had the kind of money the Discovery Institute/CSC has, who knows what they might be able to do? It's criminal that they have to scrape and struggle as they do, just to get some real science done, while these ID people are flying around the country on PR junkets -- the Discovery Institute is SWILLING in cash -- DOING NO SCIENCE AT ALL, yet claiming a place at science's table. Feugh!

I.D. is in fact an evangelical Christian movement, a fact amply documented in Barbara Forrest & Paul Gross's excellent book CREATIONISM'S TROJAN HORSE. I have absolutely no problem with evangelical Christianity, and am inclined to believe that it is on balance a strengthening force in U.S. society. It is not science, though, and its teachings don't belong in the science classroom. Everything in its proper place.

I don't know why standing up for science and against pseudoscience should be at odds with conservatism. I.D. is an outgrowth of American folk religiosity, whose political "color" is populist, not conservative. William Jennings Bryan would have socked you on the jaw if you'd called him a conservative. Again, I don't mind populism. I regularlywatch Bill O'Reilly, the foremost TV populist of our day, and even agree with him on some things. That's nothing to do with science, though. Populism and science can't mix, and shouldn't.

2) A personal question, with what you know about genomics now (I am told you have informants in the business), how cheap would a full sequencing have to get before you would be willing to pay up? (assuming privacy was safeguarded)

It's not a thing I am much interested in having done, and I am seriously poor, so I guess the answer is "real cheap." I'm talking two digits to the left of the decimal point.

3) Your Metrocon column was in part a response, or lack of, to the tendency for people to specify what kind of conservative they are. I've heard people label you a "paleocon," and been surprised at your support of Israel, or assumed you were a "neocon" because you wrote for NR but noted that you also published in THE AMERICAN CONSERVATIVE. Can you make heads or tails of all this today anymore than you could 2 years ago? Do you care?

I confess to being a bit uneasy about it. These widely-discussed categories have real meaning (as, I believe, does my "metrocon" category, whose failure to gain general currency I attribute to people mixing it up in their minds with "metrosexual"...) The different positions gathered together under one heading usually have some common philosophical foundation. If you don't fit clearly into any of them, the reason very often is that you haven't really thought things through, or are not being completely honest about your positions. I am honest -- a bit too honest for my own good sometimes -- but I am not really an intellectual. Philosophy puts me to sleep, I can't read it. I keep trying Roger Scruton's books, but I just can't get past page 30. I'm really not very good at connected thinking, and work mostly from impressions.

The upside of this is that most people are the same as me, so lots of readers see their own thought processes reflected in mine, and they like that. The downside is that I nurse a nagging sense of inferiority towards people who really have read all the deep-brow stuff, thought everything through and made a coherent belief-system out of it in their heads. Though I'd add that when I meet such people, much more often than not I find their conversation disappointing. Having a well-thought-out world-view can make a person narrow and arrogant.

Israel? The mental map that I formed in my head quite early on in life -- after reading Wittfogel's ORIENTAL DESPOTISM in the mid-1970s, I think, though reading a lot of Chinese history contributed too -- is of a world divided into civilization and barbarism. There is a civilized zone, and a barbarous hinterland. I want to see the civilized zone defended, every damn inch. Israel is a civilized country; the Arabs are barbarous. There is nothing dogmatically biological about this, and I do think that civilized peoples can slip into barbarism, and vice versa. The Vikings were very barbarous; but they developed into the pale, hygienic Scandinavians of our own time. The Hungarians did the same thing very quickly, in a couple of generations, from the terrifying Magyar horde to the Christian kingdom of Stephen. The present state of the world is what we have to deal with, though, and I want the ramparts defended. It doesn't mean hating anyone. If the Arabs "got" civilization tomorrow, I'd be the first to rejoice. Don't see any sign of it, though.

The paleo response is that it is no skin off our nose what happens in the Levant, that we should mind our own business and look strictly to our own national interests. I am quite strongly sympathetic to that, as an instinctive nationalist, but I think it bespeaks civilizational overconfidence, and my sympathy is over-ridden by my affection for Western civilization at large. Civilization is, according to me, a very fragile thing, needing constant maintenance and unblinking, vigilant defense at every boundary. If forced to retreat to the borders of the
USA, it would not survive.

4) Is it hard knowing math when the world is filled with such innumeracy?

No. I belong to that generation of Westerners from low-class backgrounds who got access to higher education far beyond what was available to our parents. We spent our teens and our twenties with the unhappy understanding that our parents, whom we loved and admired, didn't actually know much. This created all sorts of psychological stresses. It had the great advantage, though, of teaching us that good, honest, worthy, hard-working people -- lovable people, admirable people -- could be very ignorant. I like to think that this inoculated us -- some of us, at least -- against intellectual snobbery. Certainly a contempt for ordinary people -- often guiltily but imperfectly disguised -- is very common among people raised in intellectual or professional households. This is independent of politics. I know some conservatives it applies to. No names, no pack drill.

5) Over the years I've seen the following comment (in some form) multiple times: So and so is "perhaps the second most pessimistic opinion journalist right now, after John Derbyshire...." Do you think this characterization of you is accurate? Or do you think everyone else is just unduly optimistic?

Well, it depends what you mean by pessimism. I am a religious person, in a very general way -- I believe there is a supernatural realm accessible to our minds, and more real (in some way) than the natural world, which is really just a play of shadows. The fact that the natural world is a pretty nasty place therefore does not depress me as much as it ought. A nearby supernova could extinguish all life on earth in a few hours, sure -- but if you feel in your guts that there is another place beyond this one, then that isn't the end. Somehow. So on the grandest scale, I am not really a pessimist at all. On the everyday scale, though, I acknowledge that most of our nature, life, & experiences arise from the natural world & therefore partake of its general nastiness, coldness, cruelty, and gross unfairness. Civilized life fences off the horrors to some degree, which is why I am a huge fan of civilization (see above), but the fences are fragile, and the Old Adam will break through them sooner or later. Not in my lifetime, please.

As to everyone else: Yes, I think that optimism, which I would actually characterize as wishful thinking, is epidemic. This is probably a good thing. "Humankind cannot bear very much reality." I can hardly bear it myself sometimes, and I think I am a psychologically quite robust person, a natural stoic. If the bulk of humanity wants to lull themselves with wish-fulfillment dreams, I can understand that. It's just that the kid scientist in me gets annoyed when their fantasies contradict reality too obviously.

I was at a friend's house some years ago just before Christmas. My friend had a daughter, a sweet child about four years old. They were fixing little Christmas stockings to the edge of a shelf over the fireplace. The stockings didn't stick very well, though. The little girl had particular trouble with one stocking. She pressed it to the shelf, but when she let go, it fell down at once. She picked it up and pressed again; it fell down again. At last she found a solution. She pressed it to the shelf, then as she let go she simultaneously turned away so she wouldn't see the stocking fall. It was a great solution, a developmental milestone like the ones Piaget logged. I think I missed that particular stage of development, though.

6) Speaking of how you feel about other people, how does it work that Andrew Sullivan has a "Derbyshire award" even though your opinions in regards to Intelligent Design (in terms of magnitude, if not vector) and Schiavo are at sharp variance with the center of conservative punditry? Do you find it amusing or annoying to the posterboy for the nutso as well as pessimistic Right?

I don't know Andrew personally -- we have never met -- and very rarely read his stuff. The reading I have done, and the opinions of people who know him well, tell me that he is a one-issue guy. His homosexuality is everything to him, and everything he says, if you peel off a layer or two, is really about that. I have the normal and universal (according to me) distaste for male homosexuality, or at any rate for "the man who plays the part of a woman," and so do not have much time for a person who builds his entire identity around that particular thing.

As to being the posterboy for this or that; I passed age 60 this year, and am entering the zone -- I think I'm well into it, actually -- where I don't lose any sleep over what people think about me. I can lapse into what Steve Sailer calls "Elderly Tourette's Syndrome" -- i.e. saying outrageous things and smiling around blithely while everyone gags and sputters. I am really looking forward to my 60s.

7) What publications do you have to read daily?

There aren't any that I compulsively HAVE to read. I read the New York Post every morning for something to do at breakfast. (I'm a very early riser, and usually breakfast alone.) I do a half-hour browse of the Internet -- read the Daily Telegraph from ancient loyalty, the BBC news site because it's easy to navigate, a few blogs -- Steve of course, who usually has something interesting to say, Michelle Malkin, Randall Parker, a few others. I subscribe to a ridiculous number of magazines -- no wonder I'm so poor -- but I'm not sure there are any I'd really miss. The New Criterion, perhaps.

8) What is it like living with a Democrat? How are the kids being raised?

I can't really call Rosie a Democrat. Though intelligent and well-read, she doesn't care about politics. She's like Julia in "Nineteen Eighty-Four" -- what was that passage, where Orwell says that all the political jargon just went right through her, like a seed through a bird's digestive tract. That's the consequence of growing up in a totalitarian society. (I have often wondered if Orwell was talking about his own late wife, Eileen.) So we rarely talk politics, and when we do, it never gets rancorous. So politics is not a domestic irritant. The kids are only 10 and 12, so they don't know much, and the only political work I can do is to try to disabuse them of some of the sillier things their schoolteachers say. You know: keep telling them that the major figures of U.S. history are NOT Sacagawea, Harriet Tubman, and MLK. There are others!

9) If you believe there have been scientists smarter than Carl Friedrich Gauss, who?

No, I don't. He was the bee's knees. Of course this kind of thing is hard to rank, despite Charles Murray's efforts. Newton was of pretty much the same caliber, I think, though I'd say Gauss had the edge on him in breadth of understanding. And there are undoubtedly brighter gems that had the misfortune to be hidden under rocks all their lives. If the Duke of Brunswick hadn't spotted Gauss and helped him up, Gauss might have ended up a schoolmaster somewhere. But no, it's Gauss. In the realm of math there are all sorts of names that excelled him in some particular way -- Euler in industriousness, Riemann in sheer imaginative power, and so on. But net-net, Gauss is tops.

You're the top
You're Carl Fred of Brunswick.
You're the top
You're a boobs-and-buns flick.

Sorry, nervous habit.

10) Are you still thinking of retiring to China?

Not very seriously. My wife wouldn't go, anyway. She likes America too much. And I don't speak the language very well. And I'm getting kind of set in my ways, really don't want that much of a disruption. Still, for all the awfulness of communism, or post-communism, whatever they're in now, China is a fundamentally civilized place, and I have always felt at home among Chinese people. An old friend -- one of my first Chinese friends -- used to say that I was Chinese in a previous life, an idea I am quite open to. In this life, however, I am English, and in an ethnostate like China, I should always be to some degree an outsider. I think it would get on my nerves at last. Of course, if things got really bad here, I would try to find somewhere less stressful to live.

For all my much-advertised pessimism, though, I don't honestly see things getting that bad in the USA. Not in my lifetime. I am 60.


Wednesday, November 09, 2005

ID vs. creationism, what's in a name.   posted by Razib @ 11/09/2005 10:12:00 AM

In my post below in regards to heritability I was a little unclear, I consciously conflated "Intelligent Design" with Creationism. The fact is that prominent proponents of Intelligent Design, like Michael Behe and William Dembski, actually accept common descent of organisms (ergo, macroevolution). This is important because my discussions with working biologists suggests that most do not care or know of these particular distinctions. Creationism as it is conventionally understood is the "Young Earth" kind which posits separate creations for animals by a God ~10,000 years ago and a "flood geology." If you are interested in exploring the various flavors of "anti-evolutionists," The Creationists by Ronald L. Numbers is an excellent survey of the pre-1990 Creationist movement, while Larry Witham's By Design is a mildly sympathetic portrait of the intellectuals behind Intelligent Design. There are differences within both these factions, there are Old Earth Creationists like Hugh Ross, and Yough Earth Creationists associated with the Intelligent Design think tank, Access Research Network. The short of it is that the gross social diversity of the non-naturalistic evolution camp (for lack of a better term) has all the hallmarks of a ideo-political entity, not an incipient scientific paradigm. As a matter of practicality naturalistic evolutionists, as I am, as well as theistic evolutionists, form a clade which is an "outgroup" to the bushy tree of Young Earth Creationists ↔ Intelligent Design. All this matters because my personal experience is that in one-to-one rhetorical disputes it is important to understand the nuance and subtly of your opponent's position to be able to play games of divide, counter and conquer. But when it comes to more generalized public discourse, operationally Young Earth Creationists and Intelligent Design advocates can be lumped together, because their essential impact is negative. The terms are dictated by the name of the game.

Related: You might want to check out William Dembski's weblog Uncommon Descent. Personally, I see Dembski as a synthesis between William Paley and the apocryphal Leonhard Euler, but I suppose whether you see his weblog as a trainwreck or a profile in intellectual courage depends on your angle on the cultural debate he is at the center of.

Update: The two real scientists of the ID movement are Michael Behe, a biochemist, and William Dembski, a mathematician and philosopher. Here are some quotes you might find of interest:

Behe: "I'm an 'evolutionist' in the sense that I do think natural selection explains some things ... But from what I see, the evidence only shows natural selection explaining rather small changes, and I see profound difficulties in thining that it explains much more than trivial changes. It is fine by me if common descent is indeed true, and there is some sort of designed program to power changes over time (i.e., evolution). And I think things like pseudogenes are strong arguments for common descent ...."

Dembski: "Right now I'm inclined toward a preprogrammed form of evolution in which life evolves teleologically (human being the end of the evolutionary process."

It seems that both seem to be promoting a form of orthogenesis.

Source: The Evolution-Creation Struggle.

Update II: Some of you may have noticed that the Dover school board which pushed Intelligent Design/Creationism has been booted out. I'm not surprised. The public has generally favored the addition of Creationism to the curriculum. Hell, my high school earth science teacher was generally in favor of "equal time," though he accepted evolution himself. On the other hand, Kansas is swinging back toward Creationism in schools (or at least, anti-evolutionism). What's going on? One point to consider is that the public is very stupid, so take their "opinions" with a grain of salt. Most people don't think about evolution, or care much about it, and if given 30 seconds of thought they might generally favor teaching "both sides." It seems fair. But the sentiment is very shallow. Most of my friends in high school were "Creationists," but in reality, they didn't know much about evolution or creationism. It was more a cultural badge than a well thought out view about how the world worked. Similarly, most people who believe in evolution do so because it shows that they are enlightened people who aren't superstitious, they don't know the details of the process of evolution, as opposed to the fact of evolution (please note, the fact of evolution has been a hypothesis which as been floated for 2,500 years, at least). What you see in places like Dover and in Kansas are periodic swings in political motivation on a topic which isn't really very important to most people. For enlightened educated people Creationism in the schools moves a small minority to drastic action only when there is a clear and present danger (this small minority includes the intellectual and public elites, which explains why in a nation where 60-70% favor teaching "both sides" Creationism has been usually excluded from state funded schools). When that danger abates, then it is business as usual, and the Creationists start slipping back into the ecosystem. And so the cycle begins again.

Homo Secretariat   posted by Jason Malloy @ 11/09/2005 08:14:00 AM

Two new reports suggest that humans are nearing their limit of record-breaking running achievement, and that the sex difference provides no evidence of ever closing. Abstracts below the fold:

More males run fast: a stable sex difference in competitiveness in U.S. distance runners
Robert O. Deaner
Evolution and Human Behavior
Article in Press, Corrected Proof

Sex differences in competitiveness are well established, but it is unknown if they originate from sociocultural conditions or evolved predispositions. Testing these hypotheses requires a quantifiable sex difference in competitiveness and the application of a powerful sociocultural manipulation to eliminate it. Study 1 reviews previous work showing that more male distance runners are motivated by competition and maintain large training volumes, suggesting that more males should run fast relative to sex-specific world-class standards. I then use two independent statistical approaches to demonstrate that, in matched populations of male and female U.S. runners, two to four times as many males as females ran relatively fast in 2003. Study 2 investigates whether the growth in opportunities and incentives for female athletes in the past 30 years is eliminating this sex difference. I first show that there was a marked increase in the number of fast female runners in the 1970s and early 1980s, a period during which female participation increased dramatically. However, I found no indication of an absolute or relative increase in the number of fast female distance runners since the mid-1980s. These findings therefore support the hypothesis that sex differences in competitiveness partly reflect evolved predispositions.


Are There Limits to Running World Records?
Medicine & Science in Sports & Exercise. 37(10):1785-1788, October 2005.
Nevill, AM, Whyte, G

Purpose: Previous researchers have adopted linear models to predict athletic running world records, based on records recorded throughout the 20th century. These linear models imply that there is no limit to human performance and that, based on projected estimates, women will eventually run faster than men. The purpose of this article is to assess whether a more biologically sound, flattened "S-shaped" curve could provide a better and more interpretable fit to the data, suggesting that running world records could reach their asymptotic limits some time in the future.

Methods: Middle- and long-distance running world record speeds recorded during the 20th century were modeled using a flattened S-shaped logistic curve.

Results: The logistic curves produce significantly better fits to these world records than linear models (assessed by separating/partitioning the explained variance from the logistic and linear models using ANOVA). The models identify a slow rise in world-record speeds during the early year of the century, followed by a period of "acceleration" in the middle of the century (due to the professionalization of sport and advances in technology and science), and a subsequent reduction in the prevalence of record-breaking performances towards the end of the century. The model predicts that men's world records are nearing their asymptotic limits (within 1-3%). Indeed, the current women's 1500-m world record speed of 6.51 m[middle dot]s-1 may well have reached its limit (time 3:50.46).

Conclusions: Many of the established men's and women's endurance running world records are nearing their limits and, consequently, women's world records are unlikely to ever reach those achieved by men.


Related: African Endurance Running and Genetics, The Physiology of Kenyan Runners, Baby, we were born to run, Born to run!, Born to Run. (Three times the same title; pretty lame, I know. On the other hand 1) I did it first 2) I came up with Homo Secretariat - I mean c'mon!)

Also see Steve's The Gender Gap: Elite Women Are Running Further Behind

Tuesday, November 08, 2005

Response, heritability and selection (R = h2 * S), little bits and reiterations   posted by Razib @ 11/08/2005 08:32:00 PM

A few more thoughts on R = h2*S. First, h2 isn't "squared,"* it is just the narrow sense heritability, which is the additive genetic variance. For the prediction equation to be valid you need a continuous quantitative trait. In other words, not an on-off trait which we are familiar with in the "Mendelian" world. This trait should be easily characterized by a normal distribution, the canonical bell curve. A classic Fisherian perspective would hold that this distribution is simply a reflection of the central limit theorem, numerous loci of small effect are equivalent to the independent random variables which result in a normal distribution, which displays a range around a median. This last point is important, heritable traits (where some of their variation is due to additive genetic factors) are usually not extremely unequivocal in their fitness implications. The reasoning is simple, there is still heterogeneity at their loci. If the fitness deviation was either extremely positive or negative for a given allele, it should be purged or driven to fixation. Over time, one would assume that all the polymorphism across the loci, where the frequency of the modal allele at a locus is less than 95% (or 99%, depends on who you talk to), would be expunged. The "random variable" wouldn't be so random and variable and you would see a concomitant reduction in the additive genetic variance. Eventually, the trait would become classically genetic, like the number of fingers you have (this kid aside, all humans are pretty similar on this trait)

Two heritable traits are height and IQ. They are continuous quantitative traits, you can peg a number to them on a distribution chart. They exhibit both exhibit a classical bell curve (assuming a population isn't subject to famine, steroids or high stakes testing!). Though one would assume that being taller and smarter would make you more "fit," the fact that there is a great deal of intra and interpopulational variance on these traits should make you reconsider this assertion. Larger people have greater caloric needs. The brain is also an energy hog. Additionally, there might be correlated responses of other traits which would cancel out the fitness boosts as one moves up the distribution on a trait (extremely tall men often have health problems, extremely smart people are often pretty weird). One could posit a host of frequency dependent selective effects, in other words variation is preserved because a fitness equilibrium is reached between the various alleles (you get too common, and your "edge" is lost). And of course, there might be a lot of variation as a function of time, so that periodic famines increase the fitness of alleles which confer small size to males (who have lower caloric needs) before they are purged from the gene pool. Many stories can be spun from this one distribution.

Now, one implication of breeding a population using the prediction equation is that heritability should decrease if you are selecting strongly for a trait, because you are exhausting the additive genetic variation (you are purging the diversity from the loci). In practice, this takes often takes a while. Additionally, the range in phenotype you begin within is not necessarily a fundamental bound on the range in phenotype for the population. That is, the highest value within a population at generation t might be lower than the mean value at generation t + 1000, even without the addition of new alleles via mutation or migration. The reasoning is simple: in the initial population extremely rare alleles might never have combined and expressed extreme phenotypes, but, as you selected for particular alleles via their average effects on the phenotype you are shifting the underlying gene frequencies and altering the architecture. Eventually, extremely rare alleles might not be so rare, and so combinations which once might have appeared once every few generations in a large population could theoretically become modal! An important point to remember though is that continuous traits are only roughly normal. This is important because of the "fat tail" tendency of some of these traits, like IQ. There are many more high IQ individuals than a real normal distribution would predict. This discrepancy tends to increase in magnitude as you slide up the scale. Remember before that a priori we simply modeled the distribution as being due to independent additive effects across loci? This the theory, the reality is that there are almost certainly alleles of larger effect and dependencies across loci. Some of the non-linear kinks could be due to epistasis on the genetic level. Or, on the extra-genetic level they could be due to gene-environment interactions (imagine an allele which is subject to a norm of reaction which modulates its magnitude of effect as well as its propensity toward epistasis). And of course, as Michael pointed out, small deviations of the mean even in an ideal normal distribution can have outsized effects at the extremes (check it yourself computationally, I kept trying to get people to do this during the Summers fiasco).

Now, I've tried to make this concrete, but, I want to emphasize that quantitative traits and additive genetic variation are not simply empirical laws and phenomena, they can be derived a priori from basic genetics. Rather than repeat the details, I invite those with an interest to flip to the last chapter, 9, of Principles of Population Genetics (a lot of mundane multiplication of fractions if you want to know the truth!). Or, for the more historically inclined, I suggest R.A. Fisher's classic 1918 paper, The Correlation between Relatives on the Supposition of Mendelian Inheritance (PDF), where he manages to elucidate how continuous quantitative traits emerge out of the cloud of discrete mendelian genetic loci (Please note, Fisher received a degree in mathematics, and his first postgraduate academic training was in statistical mechanics in the context of physics).

Finally, I just noticed in Introduction to Quantitative Genetics that the halfway point of theoretical response to selection assuming an ideal populational additive genetic architecture and a selected proportion per generation of 1/21 is ~1.4Ne, Ne being the effective breeding population, while for recessive genes it is ~2Ne. If you look it up, it is a bit more nuanced than that, but it is a first approximation that emphasizes that the size of the population is an important factor to consider because of the range of standard genetic variation that that population brings to the table.

In this age when the soldiers of Creationism are marchin' it behooves us to remind our citizens that evolutionary theory as it emerged out of the Modern Synthesis has a strong mathematical basis. Creationists often reply that they accept microevolution as opposed to macroevolution, but the border between the two is often as fluid as the continuity which characterizes quantitative traits. Macroevolution is predicated on species level distinctiveness which implies walls between the flow of alleles between populations because of mating barriers. In fact, even something as concrete as "species" can be tenditious and fluid, as opposed to a precise type (or "kind"). In the early 1990s genetic tests confirmed that there were 3 hybrid whales who were "Fin-Blue" whales, and that one of these hybrids was a pregnant female (page 364 of Molecular Markers, Natural History and Evolution). A few weeks ago I listened with amusement as a developmental biologist rattled off exactly how he would go about hybridizing a human with chimpanzee and what sort of chromosomal rearrangements would need to occur for the possibility of a fertile hybrid to emerge from the offspring of the F1 generation. After I observed that the process seemed pretty clear in his head, the researcher smiled and explained that he was "simply extrapolating" from what he knew in regards to . Sure. Are humans fish? Actually, cladistically we are (lobe-fin fish that is, as opposed to ray-fin fish).

Addendum: A few weeks ago Jim opined that this blog was diving into "diving deep into technical genetic jargon." 1) I don't think that something like the breeder's prediction equation should be intimidating (no calculus here!), and 2) the jargon is highly salient to our everyday life, and our discussion of public policy. I simply invite those for whom this is jargonistic and technical to bear with me, I'm not the best communicator, but, I think these concepts need to be part of the toolkit of many more intelligent people. Frankly, too many biologists don't know basic population genetics! Speciation, differences and shifts between species, is really cool and charismatic, but microevolution within a species, especially the human species, is a very important topic as well. And of course my interests in history and religion haven't disappeared, and I will be posting more on those topics in the near future, just as I think non-scientists need to know about science (the means of much of modernity), I think scientists should know more about non-science (the ends of modernity).

Update: In the comments David B points out:

IIRC, heritability is symbolised as h^2 (not h) because back in the early days h was used for a correlation coefficient between phenotype and genotype, while h^2, the square of that correlation coefficient, measured the proportion of variance 'explained' by the correlation. (This is a standard statistical result: if r is the correlation between a and b, the variance of a for given b, or vice versa, is (1 - r^2)V, where V is the full variance of the relevant population.) But when someone (Wright?) later introduced the term heritability, they were stuck with the existing symbolism, which was too well-established to change.

Obviously if h2 explains the proportion of variation of the phenotype, that sounds rather like r2, the coefficient of determination, which quantifies the proportion of the variation of Y due to X. I simply wanted no one to get confused and actually take a heritability value, 0.5, and square it, when actually calculating R from h2 and S.

1 - As the proportion selected of the population from each generation drops, the S is increasing, but the Ne is dropping. The relations above are to give a rough measure, the main point is that there is a dependency on the number of breeding individuals that could contribute to additive genetic variance.

Monday, November 07, 2005

8th grade math for the rest of us   posted by Razib @ 11/07/2005 03:26:00 PM

Occasionally I appeal to formalizations or equations on this weblog to illustrate a general verbal principle. I don't do it to obscure or needlessly technicalize a topic of interest, but rather, it is often a neat and dense way to package the information and express precisely the various relations that I am attempting to communicate. Most of the formulas are extremely light on mathematical subtly, and there is little need for a level of fluency beyond what one should have attained in 8th grade algebra. The difficulty is almost always an unfamiliarity with the notation. But, the formulas are condensations of some of the general concepts that I want to communicate to readers of this blog. I know that a substantial proportion of the core 300 readers of this weblog come from backgrounds in the mathematical sciences, and the main hurdle for this subset is simply to map over knowledge from their own fields into biology (though I haven't thrown out diffusion equations here in relation to changes in allele frequency, so I'm not sure how much mapping even needs to be done, seeing as how it is almost always 8th grade algebra on display, with a little basic statistics and probability). But many do not come to this weblog from the mathematical sciences, so I am here to reassure you that you need not skip any equation or formalization, because they are mathematically quite trivial and easy to grasp. For me, formalization and mathematicization in the context of this weblog helps everyone trade in a common currency. It facilitates communication and cuts down on needless verbal confusions. Over the past 3 years I myself have slowly become more and more prone toward formalizing my genetical thinking in a "Wright-Fisher" model, so to speak. In the rough outlines little has changed, but I have gained a great deal in precision and predictivity. As I note above, this gain in precision and predictivity is attained via the most minimal acquisitions of mathematical tools. Many of the models can be easily illustrated with difference equations, which can be confirmed computationally (in MS Excel even!) because of their discrete nature (i.e., don't sweat not taking any courses in differential equations, linear algebra, probability and statistics, or, yes, even calculus! Though I think if you don't have calculus you probably will miss some of the logic and implications).

Godless & I never have gotten around to a "GNXP FAQ." The reasons are rooted in human psychology, this weblog is a hobby, a pastime, and writing an FAQ requires forethought and effort we simply never felt we could spare! Nevertheless, I do link to technical webpages whenever I can when I use an equation, and at this point, I feel I should go over a few formula that I feel are particularly useful, and good currency to have "under your belt" so that one can get beyond vague impressions and intuitions. And I want to emphasize: there really isn't much beyond 8th grade algebra here!

For example, consider the Hardy-Weinberg Equilibrium (HWE)....

p2 + 2pq + q2 = 1

p = frequency allele ("A") at a locus (def. 4) in the population
q = frequency allele ("a") at a locus in the population
p2 = frequency of homozygote A genotype in a population (that is, frequency of p squared, p X p, because you have two copies, AA, at a locus)
q2 = frequency of homozygote a genotype in a population
2pq = frequency of heterozygote genotype in a population

G.H. Hardy (most well known to the public because of his collaboration with Ramanujin) thought little of this formula, and didn't understand why it wasn't obvious for biologists! As most of you know from high school biology, if you have two parents who are heterozygotes for a "dominant" and "recessive" allele, that is, they are Aa and Aa, on a locus, and they have offspring, 1/4 of the progeny will exhibit the recessive trait and 3/4 will not (because only the 1/4 who are homozygotes, aa, express the trait). Biologists in the early 20th century actually debated why populations did not exhibit the 3:1 ratio that emerged out of the Punnet Squares. Of course, the key is that the expression of the recessive trait is a function of the frequency of the recessive allele within the population, the 3:1 ratio on a populational level is only valid where p and q are both at frequencies of about 50%.

This model has many assumptions (like all models, otherwise, they wouldn't be models!), but, it works as a good null hypothesis. You might think that it isn't worthwhile to even know this equation, but I disagree, for two reasons....

1) It gives more concreteness to your ability to think about genetic questions, and it is the basis for extrapolation of that thought. Believe it or not, HWE is the starting point for a lot of mathematical population genetic models, and for a reason.

2) A lot of the genetic issues that come up in everyday discourse are amenable to in-your-head-HWE calculations. For example, cystic fibrosis, which is a recessive disease. Or, Rh- status (again, recessive). The payoff in terms of utility is not that great, but the ease of doing the calculation in your head and being able to brush aside verbal qualifications is I think useful. Remember 3 years ago when stories popped up that 'blondes were going extinct' (it seems like it was a hoax)? As our own David Burbridge noted, this seemed a peculiar assertion to make sans massive selection (some selection was implied of course, though little evidence given as to the magnitude of differential fitness), the alleles which caused blondism likely wouldn't disappear from the population, assuming that one models it as a 'recessive' trait (I actually think the recessive-dominant talk confuses more than helps, but that's another post).

So, with the preliminaries over, on to a few trivial issues which I hope to bring to your attention. I want to first excuse myself of any pretense at a high standard of rigor and formality, the threshold for success is low if we get beyond vague verbal platitudes. There are lots of different notations, and I'm mildly constrained by the formatting of HTML (no, I don't want to use MathML, this is not a math weblog, and I don't want to give people bizarre javascript warnings). So bear with me....


Vp = Va + Vd + Ve + Vi

Vp = Variation of the phenotype (trait)
Va = Additive genetic variation
Vd = Dominance genetic variation
Ve = Environmental variation
Vi = Interactional (epistatic) variation

Normally you should see some σ2 (where I put the V's) to make it clear that you are talking in terms of statistical parameters of variance. Roughly speaking, all that matters is that the variation of a given phenotype attributable to a subcomponent is being illustrated here. If you want to get into the nitty-gritty of this equation, the last chapter of Principles of Population Genetics is nice, while Introduction to Quantitative Genetics really does more than "introduce" you to the nuances of this formalization. But, on this weblog we have talked about Va a lot, because that is what is to a large extent responsible for the normal distribution you see on continuous quantitative traits. When we are delving into psychometrics, this really matters. But, to get less contentious, let me use height as an illustrative trait. Clearly there is a median and modal height, an "average," and variation around this average. Some of this is no doubt due to genes, we see rough relationships between parents and their offspring. But the key is that the relationship is rough, there are other components of the variation. As Francis Galton first noted, if you plot offspring height against parental height one notes a correlation, but an imperfect one. Va, the additive genetic variance, is roughly proportional to the regression coefficient of the line of best fit. In plain English, the similarity in height between a population of parents and their offspring (correct for sex) is due to Va. Va on the genetic level can be thought of as constituted by genes of small effect across the loci. Going back to the notation I used for the Punnet Square, instead of just AA, Aa and aa on a locus, imagine multiple loci, each with its own cluster of alleles, and each contributing a small increment independently to the phenotype. A large number of random variables of small effect will tend to result in a modal, that is, most frequent, value that is also intermediate on the range of the distribution (see central limit theorem, I don't know how to put this in plain English well). But here is the key: the Va, which is basically the "narrow sense heritability" is the populational proportion of variation, it doesn't mean much on the individual level. This is important because a recurrent problem on this weblog is that people have conflated the point and taken a stand on the "Nature vs. Nurture" issue by stating that "I believing that the trait X is mostly genetic/environment." Though the gist of the comment is well taken, the way the phrase is put suggests a misunderstanding of the details of what is being communicated, that is, these values explain populations, but are not necessarily relevant when speaking, or conceiving of, individuals.

Additionally, the calculation of these values is often problematic. I have also left off the important confounding parameters of gene-environment association and gene-environment interaction. The former is basically an increase of the dispersion because of the correlation of particular genotypes to particular environments (the classic example is the increase in feed to extremely productive dairy cows, this obviously increases the difference between the animals in terms of their milk productivity since the environmental variable is different across them). Gene-environment interaction is even more difficult, as it involves the unpredictable reactions of genotypes to varied environments. This is the classic norm of reaction problem. The epistatic gene interactions are also important confounders of the idealized genetic world, as gene-gene interactions break up the calm of the additive independent loci universe. In sum, this idealized model is an utopia which is never attained in the real world. Does that mean we should give up on this formalization?

Developmental psychologist Alison Gopnik noted earlier this year:

Because humans create and change their own environments we don't and can't, in principle, know what the range of possible environments will turn out be. And we don't know how those possible environments might interact with genetics over the course of development to cause a particular distribution of adult traits. This means that we simply don‘t and can't know how much genes contribute to complex human traits in general — the question is incoherent. In a particular case, with a particular specified environment, and a complete developmental history of the causal interactions between the organism and the environment, we might be able to give a causal account of the path from gene to trait. But there is no general answer about how gene and trait are related across all environments.
Frankly, I wonder why Alison Gopnik is not a solid state physicist or a novelist, because these types of assertions make me wonder as to validity of any attempt at a rigorous and predictive intellectuality any softer than molecular biology! Ultimately, such stringent standards for controlling of variables seems to render only the purest of humanities and the hardest of sciences immune from the taint of noise, the former because of its unalloyed reliance on intuition, and the latter because of its recourse toward deterministic models of extremely precise caliber. Why is Alison Gopnik a developmental psychologist? Does her "Theory Theory" stand up to the scrutiny of this standard? I doubt it.

The fact is anyone who is doing work in a noisy and statistical science is very well aware of confounding factors. It is part of the business. But even in the midst of the murkiness of the complex and messy world around us, we attempt to model it as best as we can. This is what Gopnik is doing in her corner of cognitive science. This is what public policy analysts do when they decompose and examine topics of human importance in a rational manner. If the critiques of the likes of Gopnik are taken to their logical conclusion, outside of the physical, and to some extent biophysical, sciences, all we will have recourse to are customs, traditions and a priori values. Is this what Gopnik would want? If you read Curious Minds, you will get a feel for the cultural milieu that Gopnik grew up in, and her personal biases in terms of politics and culture. I doubt that she would be excited about mapping her views expressed above to other fields. I have pointed out this hypocrisy before, that the norms and biases we hold tend to hold result in wildly different standards of rational integrity and model building depending on the domain we are addressing. As a cognitive scientist, Gopnik should know better!

There are two key problems here which is the real root of Gopnik's issue (at least on the objective big picture scale as opposed to tactical sniping within-field). Verbal expositions about variation tend to underemphasize the various subcomponents of the variation, amongst those "in the know," the problems are known, accounted for, and we keep moving on operationally with our mental process. But, amongst those not in the know, it seems we are ignoring the other components of variation. Obviously this is a function of clarity and reiteration. But, there is another problem: the tendency toward cognitive models to canalize into typologies. Two independent variables contribute to this specifically, human bias toward slotting statistical-populational concepts and trends into idealized types, boxes, bins and categories, usually in relation to "theories" in a Gopnikesque manner, and, frankly, stupidity. A large proportion of the human race, perhaps the vast majority with sub-115 IQs, simply can not understand basic statistics, conditional probabilities, and so on. But even for those whose intelligence and motivation is high, it can be difficult to break out of preconceived boxes. The "Nature vs. Nurture" box is a very powerful one, and I believe it coopts a natural tendency to think in terms of black and white dichotomies. We have to climb up the hill of our biases with the rope and ladder of logical-abstraction, and allow ourselves to be guided by the system and the mathematical logic. Simply keep the faith alive!

OK, enough polemics, I want to leave you with some positive.

R = h2 X S

R = response, S = selection and h2 is the narrow sense heritability I mentioned above (additive genetic variance). You often hear talk of evolution, but what about quantitizing how fast it occurs? This "prediction equation" comes out of animal breeding, but the basic principle is obvious, the response to selection is a function of the amount of selection you are engaging in (i.e., selecting a subset of the overall population via some truncation for minimum phenotype value) and the narrow sense heritability. Over time if the selection is strong enough the additive genetic variance should be exhausted, and "evolution" should stop. This sort of start-and-stop gradualism is common in microevolutionary processes (though even in breeding it takes a while, especially in a large population). When someone wonders if black Americans are somehow more robust because of slavery, remember, you need to have high heritability and strong selection for "robustness" to be shifted in just a few generations. You too can "do the math"!

Molecules and phylogenies

Back in the mid-1980s we started hearing a lot about "African Eve." As we note on this weblog, there were two parts of this:

1) A caution not to overread the results into imagining a single foremother.
2) The popular press basically ignoring this caution.

But here are a few "fun facts."

1) The probability of fixation of a new mutation is 1/2N, where N is the population size.
2) The time until fixation is usually 4N, where N is the population size.
3) 1/2N X 2Nμ, where μ is the mutation rate, reflects the reality that the probability of mutation times the rate of mutation results in the substitution, the turnover of alleles, on loci being a function just of mutation rate (μ).
4) Time until extinction of an allele is usually 2Ne/N X ln(2N).
5) The long term effective population is 1/t(1/N0 + ... + 1/Nt - 1).

You can do some "plug & chug" in Excel if you want to check out the long term effective population, but trust me when I tell you that it is far closer to the low bound as a function of time than the high bound as far as what your intuition would tell you. That is, population bottlenecks are extremely salient demographic events, and tend to be important even after the population bounces back. This also should make one cautious about assuming that larger populations have more genetic variation than smaller ones, that is only true if you correct for the long term effective population, as often large populations are simply "blow ups" of small populations. Probability of fixation, extinction and time until fixation should give you a clue as to an important fact: lineages come and go, the only thing that is inevitable in a world without selection is extinction. If you go back 100,000 years, about 5,000 generations, it stands to reason that most lineages will have gone extinct. Think of it like surnames that are passed through the male line, how likely is it going to be that a surname will be passed for 5,000 generations through an uninterrupted line of males? (remember, mtDNA is passed through females, flip the logic!) Using some of the equations above, and considering the wild fluctuations in population size that were likely in the past, the caution seems a lot more solid I think.


r X B > C

The logic of kin selection. r = coefficient of relatedness, roughly, the chance that an allele picked from a locus will be identical by descent to an allele selected from another individual at the same locus (i.e., 1/2 between siblings, 1/2 between parents, 1/4 between grandparents & grandchildren, etc.). B = is the fitness benefit and C = cost. It's a simple way of thinking about the world, kin clearly matters. As J.B.S. Haldane was reputed to have said he would "give up his life for 2 brothers or eight cousins" (1/2 r to a sibling, 1/8 to a cousin, makes sense).

But here is one thing to consider, recent literature reviews I have seen in Molecular Markers, Natural History and Evolution as well as Cooperation among Animals suggests that kin selection can not explain the full range of eusociality amongst haplodiploid hymenoptera across that taxon. They were William Hamilton's original models because sisters are more closely related to each other, r = 0.75, than they would be to their own offspring (r = 0.5) since males are haploid. In many species the coefficients of relatedness are empirically far lower the idealized kin selection models due to multiple queens and multiple inseminations of each queen (there weren't genetic tests when Hamilton published his original paper in The Journal of Theoretical Biology). And yet eusociality exists amongst them, just as in other species who do fit the ideal kin selective parameters eusociality also flourishes. The explanatory bubble seems to have burst...or has it? One solution is that kin selection might have been the necessary condition for eusociality to evolve, that is, the ancestral state, but once eusociality was a feature of this class of organisms other mechanisms also appeared to reinforce it, allowing the relexation of the necessity for a high coefficient of relation.

This is not to deny Hamilton's point or his logic, but, like Triver's reciprocal altruism, or the older ideas of group selection, I think it should makes us cautious of "one formalization to rule them all!" Gopnik was right in that, generalization is a difficult enterprise in higher order biology, and even more difficult in the human sciences (hard to do controlled lab tests!). But that does not mean that formalization is all for naught. In the sciences we should attempt to achieve the maximum level of predictive power with the minimum number of parameters. If a given species requires a synthesis of various models in a layered palimpsest, that's life. Model building must continue, because even if each model is only a brick, the house needs those bricks to ultimately be completed.

OK, I was going to hit a lot more equations and formulas...but I've already gone WAY too long because of my inability to shut up with the words. Perhaps I'll revisit this topic. But, here are some books you might find of some interest:

Principles of Population Genetics
Genetics of Populations
Introduction to Quantitative Genetics
Genetics and Analysis of Quantitative Traits
Narrow Roads of Gene Land
Evolutionary Quantitative Genetics

ScienceWeek Idiots   posted by Jason Malloy @ 11/07/2005 02:33:00 PM

Uh oh, the backlash against Bruce Lahn is beginning. At first report of the big news, many "Science for the People" [sic] types, tried to play it cool, like none of it threatened them: Lahn and his research were Good, it was just those awful racists misinterpreting his work. But as the reality sets in of what's to come and what it all means, Lahn will find his "mainstream" defense on the wane (if you think critics denying to the high heavens clear evidence for selection was troubling, just wait until issues like intelligence testing enter the mix, that's when the real obfuscation begins). The "editors" at ScienceWeek blog take issue with John Derbyshire's recent National Review piece on Lahn, but that's not surprising, more interesting is the fact that Derbyshire isn't the point, he's just their brief launching pad for slamming the Lahn team themselves; and I must say it's a real pathetic sight. Foremost they take umbrage at the implication that brain size has anything to do with intelligence - of course as the most encephalized animal we are smart enough to know that such an idea is ridiculous:
. . . [the research group of Bruce T. Lahn] nowhere discuss the important fact that within and across present human populations, studies of brains without pathology show no evidence of correlation of brain size with brain function or cultural "achievement". Certainly, if the authors are working on genes apparently associated with brain size, and the authors are also interested in relating their work to current anthropology, one would expect some discussion of their problem, to wit: If greater human brain size is still undergoing evolutionary selection, how come we have no strong correlations between brain size and important functional attributes of the human nervous system? If the brain is still evolving in size, what are the conceivable selection pressures, given no apparent correlation between non-pathological brain size and function? We're unhappy that the authors were not urged by the referees to make some statements about these questions.

Hmm, these quote-unquote "facts" sound a little a lot like complete lies. Not to mince words, I'm just going to quote at length from Thompson and Grey's 2004 paper (PDF) from Nature Reviews Neuroscience:
Imaging studies of intelligence and brain structure. Correlations between intelligence and total brain volume or grey matter volume have been replicated in magnetic resonance imaging (MRI) studies, to the extent that intelligence is now commonly used as a confounding variable in morphometric studies of disease. [compare with "brains without pathology show no evidence of correlation of brain size with brain function"] MRI-based studies estimate a moderate correlation between brain size and intelligence of 0.40 to 0.51. [compare with "no apparent correlation between non-pathological brain size and function"] One MRI study determined the volume of 13 brain regions, and found that the brain regions intercorrelated substantially - a general factor (the first unrotated principal component in a factor analysis) accounted for 48% of the variance. We found that g was significantly linked to differences in the volume of frontal grey matter, which were determined primarily by genetic factors . . . this analysis underestimated the extent to which grey matter volume in each brain region correlates with g. We reported partial correlations that indicated the association between the volume of each brain region and g, independent of other brain regions. In other words, the volume of frontal grey matter had additional predictive validity for g even after the predictive effect of total brain volume was factored out (as is common in morphometric studies).

Posthuma et al. extended these findings using a cross-twin cross-trait (bivariate genetic) analysis to compute genetic correlations. They showed that the linkage between volume of grey matter and g is mediated by a common set of genes. Intelligence therefore depends, to some extent, on structural differences in the brain that are under genetic control, indicating a partly neuroanatomical (structural) explanation for the high heritability of intelligence.However, brain structure is not completely determined by genes - learning a difficult perceptual-motor skill (juggling) induced a 3% increase in the volume of grey matter in visual attention areas. Although such plasticity has not been shown in all regions of the brain, it is possible that the volume of grey matter is correlated with intelligence partly because more intelligent individuals seek mentally challenging activities that increase the volume of their grey matter."

I encourage you to read the PDF and note the references. I also encourage you to read two more references. First yet another brain size and intelligence meta-analysis (PDF) was published this year by Michael McDaniel. The correlation between brain size and measured intelligence is again about .4 for adult men and women, and a little bit lower for children. Second, for the functional relationship of this correlation, you should read Gilles Gignac et al's chapter 6 in Scientific Study of General Intelligence.

Bottom line: the editors at ScienceWeek are blaming Bruce Lahn for their own ignorance. Besides lying about what the literature does show, they also have the gall to be outraged that Lahn doesn't similarly rely on their own poor sources from the 1960s:
We're also fascinated by the opening sentence of the first paper: "The most distinct trait of Homo sapiens is the exceptional size and complexity of the brain (1,2). That's good, but the problem is the two references are 46 years old and 32 years old, respectively, and we're trying to imagine why anyone would choose these particular references for a report of such research. If we're to choose old references, why not choose von Bonin? But maybe that would be against the approach of these authors. Consider, for example, the following quotation from von Bonin:

"The results of our inquiries into the brains of fossil men are somewhat meager: we cannot deduce any details about their mental life, whether they believed in God, whether they could speak or not, or how they felt about the world around them... That the brain increases in size as we go from the Australopithecinae to modern man -- or to the Upper Paleolithics, for that matter --is quite obvious and, of course, gratifying. But the meaning of the increase is again not quite clear because, as we all know, brain size as such is a very poor indicator of mental ability. This has been shown best perhaps by Pearson (1925) some years ago. In his series, very gifted persons, such as Leon Gambetta, Anatole France, or Franz Joseph Gall, had very small brains, of about 1100 grams. Other equally gifted persons had very large brains; thus Byron and Dr. Johnson had brains of about 2000 grams. And, of course, some very ordinary persons had equally large brains. So brain size was certainly not very important, and the correlation between brain size and mental capacity was insignificant. But whether this argument can be extended to an evolutionary series is again another matter. For one thing, we know far too little about the bodily proportions of fossil forms. Obviously, the brain stands in a certain relation to the rest of the body, and this rest is still largely hidden from us. Brain size as such is none too meaningful. Moreover, mere size completely leaves out of account the inner structure of the brain, which may be different in different forms and which may determine to a great extent what the brain can do." Gerhardt von Bonin: THE EVOLUTION OF THE HUMAN BRAIN University of Chicago Press, 1963, p.76

So why cite Spuhler (1959) and Jerison (1973) rather than von Bonin (1963)?

Its hard to emphasize how stupid and ignorant this argument is, so I've thought of a good way to illustrate it. Why did the Lahn team reference Harry Jerison's book, Evolution of the Brain and Intelligence, that ScienceWeek finds so archaic and stupid, and not Gerhardt vo Bonin's? Maybe because Jerison's work was revolutionary and is still wildly relevant to the subject and area of study, while Bonin's is a fossil. In the Preface to 2001's Evolutionary Anatomy of the Primate Cerebral Cortex Dean Falk writes:

Beginning with 1973 publication of his classic monograph, Evolution of the Brain and Intelligence, Harry Jerison's ongoing research has had a profound impact on the questions, methods, and theoretical framework that continues to shape the field of brain evolution. On April 2 1998, researchers from Europe, Africa, and the United States gathered in Salt Lake City at the sixty-seventh annual meeting of the American Association of Physical Anthropologists to take part in a symposium that recognized and celebrated Harry Jerison's intellectual influence on the development of our discipline.

The prologue is written by none other than Stephen Jay Gould, widely celebrated among lay intellectuals for his Mismeasure of Man which lampooned many 19th researchers for seeking a link between brain size and intelligence. Gould describes his early resistance and eventual conversion to Jerison's work after realizing that Jerison truly "delivered the goods" - or, as Gould's title pithily informs us, "Size Matters". [1]

But the semi-recent Internet tool of Google Scholar gives us an even better way to demonstrate it is the ScienceWeek editors, not Bruce Lahn and company, that are truly out of date. In addition to finding papers, GS also gives us a rough indication of how important (or unimportant) a reference has been, by telling us how many other scholarly works have cited it. Then by clicking on that number we get a list of those references, including their dates, and also how many times those references have been cited - giving us an important glimpse into where the beefs at. For instance typing in 'HJ Jerison Evolution of the brain and intelligence', we see that Jerison's book has 231 citations. Clicking on that we see that many of those citations are also highly cited. All of the ones on the first page are cited at least over 50 times. The citations are also very recent, indicating, contra ScienceWeek, that Jerison's book is still relevant to current research. All of the references on the first page are post 1980, a majority are from mid to late 90s, and the rest are post-2000 (including the Falk volume above) . In contrast, we find that 'G von Bonin The evolution of the human brain' has 1 citation! And that citation has 4 citations which themselves trail off to nowhere.

In other words it's a no-brainer why Lahn's team cited Jerison's book instead of von Bonin's. To steal their condescending rhetoric, I suggest the editors "do more homework". But given their editorial earlier this year that Larry Summers comments might be "possible evidence of brain damage", the possibility of their objectivity and honesty on these issues is, of course, highly in doubt. I expect many more shoddy, deceptive attacks on Bruce Lahn and similar genetic researchers in the coming years.

[1] Also, at the risk of being obvious, I should point out that referencing a book first published in the 1970s because it pioneered a set of ideas is not the same as saying those ideas ended or stopped developing in the 70s. The Falk book is just one collection proving that Jerison and the field have expanded on those original insights ever since.

Actually, given the transparent reason for their opposition, the ScienceWeek folks should be grateful that the Lahn team didn't instead point to the most recent Jerison summary, which is in the 2002 psychometric volume The Handbook of Intelligence, where Jerison not only states that the distinction between the significance of brain size between species and within species is false, but affirms the existence of human race differences in brain size too. He don't connect them, but the dots they ain'ts hard to connect.

Good News   posted by Fly @ 11/07/2005 02:06:00 PM

UCLA scientists use statins to overcome learning disabilities in mice

“In a surprise twist that recalls the film classic "Flowers for Algernon," but adds a happy ending, UCLA scientists used statins, a popular class of cholesterol drugs, to reverse the attention deficits linked to the leading genetic cause of learning disabilities. The Nov. 8 issue of Current Biology reports the findings, which were studied in mice bred to develop the disease, called neurofibromatosis 1 (NF1).

The results proved so hopeful, that the Food and Drug Administration approved the use of the drugs in three clinical trials currently under review to test the effect of statins in children and adults born with NF1. The findings could help the estimated 35 million Americans who struggle with learning disabilities.”

"This is mind-blowing – we think we have a real fundamental reason to be optimistic," explained Silva. "Here is a drug that affects a key learning and memory pathway, and completely rescues the most common genetic cause for learning disabilities. We don't have to do extensive clinical trials for toxicity or safety – these were already completed for other uses."
"NF1 afflicts one in 4,000 people, about one million people worldwide."

I don't know where they get the estimate of possibly helping 35 million Americans, but even if it ONLY helps one million people, it is good news.

Format sidebar   posted by Razib @ 11/07/2005 12:19:00 AM

I've now created a format sidebar option, which will be permanently available on the top of the sidebar itself. The feeds are now turned off by default because occasionally they are very slow, and if you use Internet Explorer the full page does not load until every last packet has trickled in. I suggest that you get Firefox or Flock, as these browsers load the page sequentially, and I specifically placed the sidebar to the right so that you can view the content even if the bits of code don't load properly (i.e., the blogrolling script). But, if you use Internet Explorer, as I said, the feeds will be turned off. Additionally, you can mask/hide other portions of the sidebar, and your preferences will be saved in a cookie the next time you visit. It's all pretty self-explanatory, if you can't figure it out, you shouldn't be reading this weblog in the first place.

Update: Doesn't seem like the feature works on Flock. It does work on Firefox and Explorer. You are dead to me if you use other browsers (this is just so I don't get emails and complaints from every Safari, Opera and Konqueror user out there).

Update II: Use cautiously in Safari. Looks like I can make things disappear, but not reappear (i.e., the cookie settings seem to persist within session).

Sunday, November 06, 2005

Avain Flu images   posted by Scorpius @ 11/06/2005 07:30:00 PM

The Swedish newspaper, Dagens Nyhete, has just released electron microscopic images of the H5N1 strain of the avian virus. I present them here without commentary (unless someone wants to step up and translate Swedish for me), here is the slide show

No real reason to post this other than sometimes science images are simply cool.

Update This Breitbart article on the Swedish Newpaper article says that the viral particles are the "string of blue balls attacking and destroying healthy pink cells." but looking at the photos (without the benefit of a translation) it seems to me that the viral particles are the greenish-yellow clusters attacking the pinkish healthy cells with the bluish invaginations being the newly lysed cells.

Update II Thanks to everyone who pointed out that I linked to the wrong article. This is what you get when you get all excited about an article in a foreign language you do not understand at all.

Saturday, November 05, 2005

Molecular Genetics   posted by Fly @ 11/05/2005 08:51:00 AM

From “The Genius” blog. (From a link by Jason Malloy.)

“If you have academic access to Nature magazine you should totally check out this awesome movie thing about RNA interference and silencing. Watching stuff like this, I think, gives you good little models to play with in your head when you are trying to think about this stuff. From now on, when I think of Dicer, it will do that cool spinny thing to chop up the dsRNAs.”

I don’t have academic access to Nature but the link worked fine for me. Definitely worth a look.

Friday, November 04, 2005

Considerations on Alito's Casey Ruling   posted by TangoMan @ 11/04/2005 07:19:00 PM

I've been a silent observer of the recent debate about Justice Alito's ruling in Planned Parenthood v. Casey and have witnessed varying levels of sophistication in the arguments and responses from all sides of the issue. Jeff Goldstein at Protein Wisdom makes a good faith effort to argue that supporting spousal notification doesn't necessarily imply that one supports a religiously-based effort to strip away a women's right to control her own reproductive health. On the other side of the sophistication metric I've read the conspiracy inclined stylings of Garance Franka-Ruta and the feminist "patriarchy around every corner" perspective of Pandagon.

It seems the anti-spousal notification forces have drawn a line in the sand and oppose any form of notification, even with the exceptions that are designed to protect women that are noted in the Pennsylvania legislation. Which leaves me with a few questions. At what point during a pregnancy does a husband have any right to be informed about the health of the fetus? Is it only the decision on abortion that must remain hidden from the husband or does this line of reasoning extend to all decisions regarding the fetus?

Consider this situation: A husband and wife are at the doctor's office for a consultation after some routine lab tests on the pregnant woman. High levels of maternal serum a-fetoprotein concentrations were obtained in the first trimester of pregnancy and this is highly indicative of myelomeningocele, or Spina Bifida, in the fetus. An amniocentesis procedure is recommended. Clearly it will be the woman who will have to undergo the procedure but the Anti-Casey line of reasoning would preclude any notification to the husband about the wife's medical procedure or for that matter, any information on the condition of the fetus. Should the husband be asked to leave the consultation for fear that the physician will be breaking patient confidentiality by simply assuming that the wife wants the husband to hear the news with her, in effect being notified of the condition of the fetus and the procedures that are to be recommended?

After the amniocentesis the physician recommends intrauterine surgery at 25 weeks gestation. The procedure will involve either an endoscopic surgery or a more invasive procedure of opening the mother's abdomen and uterus, partially removing the fetus and sewing shut the opening over the fetus's spinal cord. Now that surgury is to be performed on the actual fetus does the father have any right to be notified of the impending procedure? Does the father have any right to consent to the procedure which is to be conducted on his child? Of course, if this procedure was done on a prematurely delivered baby the father's rights would automatically be granted.

The obvious distinction between the two cases is that the fetus is still within the woman and only the woman can decide for herself the questions that pertain to her own health. Depending on the jurisdiction in which this couple reside, the woman may still have the right to abort the fetus and make the decision independently of her husband's wishes. However, many states impose restrictions on the freedom to abort as the length of gestation progresses. So at what point in the pregnancy does a father have the right to be notified of his fetus' health status, if at all? For the anti-notification advocates, does it all really boil down to "My Body, My Choice, Our Obligation? Is there room for gradualism or is such a position tantamount to a restriction on a woman's right to reproductive freedom? If a gradualist expansion of a father's right to be notified of, or consent to, a medical procedure for a fetus is considered a threat to the right of reproductive freedom then how is reproductive freedom itself defined? It would seem that the definition is quite expansive if it also incorporates medical decisionmaking on behalf of a fetus that will continue to term. The reproduction and the continuance, or discontinuance, of the pregnancy are not at issue. The health and welfare of the woman is not at issue. The crux of the issue is the health of the fetus and notification to both parents of relevant information. Are fathers absent all rights until the moment of birth or do those rights gradually come into existence? If those rights do gradually come into existence then does the Anti-Casey position with regard to notification weaken as the length of the pregnancy increases, before it become self-evident, of course? As you can see I'm having a little trouble understanding the full parameters of the controversy. Can anyone help clear up the details?

Neural Wiring   posted by Fly @ 11/04/2005 04:36:00 PM

Scientists Crack Code for Motor Neuron Wiring

“Dasen's functional analysis revealed a Hox coding hierarchy. “He found that the Hox proteins involved in pool identity are different from those involved in column identity,” said Jessell. “So from these data, the idea began to emerge that within the chromosomal Hox clusters, some Hox proteins are dedicated to broad aspects of motor neuron differentiation, and others to finer aspects of diversification. Ultimately, what crystallized from these experiments was a code — an organized relationship between Hox proteins, their chromosomal organization, and the differentiation and connectivity of motor neuron pools,” he said.

Jessell said this code appears to govern three levels of motor neuron organization: the columnar organization that ensures that motor neurons project into the limb; the divisional organization of motor neurons that determines whether motor neurons project to muscles in the dorsal or ventral halves of the limb; and finally, the motor neuron pool identity that governs the muscle target of each set of motor neurons. In a key set of experiments, Dasen showed that alterations in Hox expression patterns in specific neurons resulted in changes in motor neuron identity, and in their connectivity to muscle targets.”

“The studies also raise the possibility that the combinatorial code contains additional information, beyond the regulation of motor neuron wiring. “This is still conjecture, but the sheer number of Hox proteins, and their capacity to direct neuronal differentiation, suggests that they may also impart identity to the interneurons that enable them to connect selectively with motor neurons. And, aspects of the code could also give identity to sensory neurons, enabling their connections with motor neurons,” said Jessell. Deciphering the entire Hox code could provide crucial insights into the organization of the complex circuitry that the spinal cord uses to control muscle action.”

(Warning: leaving the realm of science and entering Fly speculations…or fantasy. Erroneous info ahead.)

We have two pieces of the puzzle. The Hox proteins provide a label (or trigger) that tells a cell what it is. We also have gene chips and protein chips that can tell us what genes are turned-on and what proteins are being built. So what occurs in between?

I believe there is DNA whose expression is triggered by the Hox proteins and that DNA controls the cell specific gene expression. I think of this DNA as scripting code. The scripting DNA wouldn’t directly code for the common structural, enzymatic, or signaling proteins.

The scripting DNA would be short in comparison to most protein-coding DNA. A mutation in this DNA would only affect specific cell types so evolution of the scripting DNA could lead to optimal gene expression for different tissues. (Whereas a mutation in most protein-coding genes would affect many cell types.) Since the scripting DNA would be short, mutations would be infrequent so less selection would be needed to maintain genome quality. Scripts would be built on top of other scripts. Low-level common scripts should be highly conserved.

The scripting DNA should have a distinctive nucleotide signature. Unlike protein-coding DNA, every nucleotide could be significant. The script DNA would be copied into RNA that would then fold into specific functional shapes. So the RNA functional shape patterns should be represented in the DNA sequence patterns. (Some scripting DNA could act through regulatory proteins. My guess is that nature doesn’t care if “machine code”, “C code”, or “scripting code” is mixed together into a complex jumble.)

My guess is that most of the design information for an animal is in this scripting DNA. Protein-coding genes tell how to build blocks and scripting DNA tells how to put the blocks together to form an animal.

What would be scripted?

Consider brain wiring. How is one neural cluster connected to another by a nerve bundle? First each cluster of neurons must travel to the proper location in the brain. The body has many fluid pathways. There is the blood circulatory system, the lymph system, and slow fluid flow from the blood system through the tissues to the lymph system. (In the earliest embryonic stages, diffusion would play a major role. As the embryo grows I’d expect fluid flow to become more important.) Thus the entire body is a drainage system with directional fluid flow. These fluid flows serve to pass chemical signals from one place to another. So chemical gradients could be used to guide cells to their destination. Each neuron type would need its own address (Hox proteins?) and instructions that convert that address into directional movements (DNA scripts?).

Once in place, the neuron sends out chemical signals. Somehow two neural clusters recognize specific signals and axons grow to connect the regions. Some of the guiding is constrained by body architecture. The axons are going to flow along the body fluid paths carrying the proper chemical signal. But occasionally the axon is going to have go against the main fluid flow and follow the chemical gradient generated by the target neurons. So DNA has code for the target neurons releasing specific signals and for the source neuron axons to respond to those signals and grow toward those targets.

There may be many unique chemical messengers and many unique receptors. (Protein-coding genes with alternate splicing could generate the unique types. A DNA script could be translated into RNA that interacts with intron RNA to control mRNA splicing.) Or there might be many ways for a cell to interpret chemical signals. Suppose a neuron axon is tracking three chemical signals. The neuron might track signals with a special ratio of those three types. A DNA script that controlled the ratio of cell membrane receptors for those signals might determine what signals caused the largest response. Or perhaps a neuron recognizes a time varying pattern of chemical messengers. There are many ways that signals can be sent and recognized. All of the ways require DNA information.

Clearly the wiring isn’t determined down to the individual neurons. But there are many nerves and many specialized brain modules. Thus the information needed to wire the human body must be extensive.

Also consider instinctive behavior. Every instinct is embedded in neural structures. So there must be DNA that codes for specific neural patterns that underlie specific instincts. So even more information is needed to build that brain.

Why do I think that scripting DNA exists?

I don’t believe there is enough information in the protein-coding DNA to build a human being. There is twice as much non-coding DNA conserved in the genome as there is protein-coding DNA. Since the scripting DNA would tend to be shorter than the protein-coding DNA it could hold much more design information. Scripts could be built based on top of lower-level scripts making the information storage more efficient. Our cells contain elaborate molecular machinery for manipulating DNA and RNA. So there are many mechanisms by which DNA/RNA might regulate gene expression or protein production without requiring a protein intermediary.

A wrinkled landscape   posted by Razib @ 11/04/2005 12:13:00 PM

One of the most important things to remember about genetics and its effect on phenotype is the concept of correlated response. That is, you select for trait A, and you get a response from trait B, likely because A and B are both partly dependent on gene 1, which has pleiotropic effects. Antagonistic pleiotropy is this phenomenon in action in the world around us, selecting for long life tends to have correlated response in terms of reduced fecundity, so the two traits balance each other out at an equilibrium that maximizes fitness (obviously if you select for fecundity to the point that survivorship goes down too fast in the life history of an organism it might have fitness implications as the offspring might have benefited from parental protection). I only bring this up because of the hot or not post below, and musings about why there might even be variance on the metric of estrogenically induced beauty (i.e., if a trait is extremely beneficial, the population should shift toward reduced variation over time as positive alleles fix on a local at 99% frequencies, at which point it might become a genetic trait). If one assumes that estrogen levels have a causative influence on two traits, "beauty" and "fecundity," and if one of those traits (fecundity) has strong fitness implications, it makes sense to use the other as a proxy for fitness since the correlation between the two is strong due to a common variable. So why is there variation in beauty anyhow? If Geoffrey Miller has your ear, he would tell you it is a good proxy for individual mutational load, as he argues The Mating Mind. Mutations are simply a fact of the universe around us, not only do we inherit mutations from our ancestors, as individual humans we generate novel mutations de novo (I have seen estimates around potentially lethal 3 mutations per individual, the lethality being masked by a "good copy"). Because of variance around the expectation of a given number of mutations there will be a range of mutational load across the population, and even within a family. Even if a mutation doesn't kill you, the "masking" is likley to be imperfect, and the number of bad copies of a gene you carry might increase your predisposition to developmental problems which could result in asymmetry and other related traits. Some would argue that the sole reason males exist is to purge the genetic load out of a breeding population via the reproductive skew toward those individuals who are on the low tail of the mutational distribution (see Why Sex Matters for a human illustration of this model).

But back to point about correlated response. First, let me add the caveat that one must be cautious about connecting correlations together...but, bear with me and be generous with your credulity. Perhaps the variation within a population of females of relative testosterone levels (ergo, masculine features vs. feminine features) is partly a byproduct of correlated responses? Consider the fact that testosterone tends to correlate with sex drive. If women with higher testosterone levels do have higher sex drives, perhaps they are simply an "alternative strategy" that persists within the population? This might be because of frequency dependent effects, or because temporal variations in the fitness landscape (i.e., sometimes it pays to be promiscuous, and sometimes it doesn't). Additionally, I have read that women with higher testosterone levels tend to produce more sons (ratio). Again, in certain contexts this might be beneficial for fitness. And finally, perhaps women with more testosterone birth sons with higher basal levels of the hormone, and the sons are therefore far more fit than those of beautiful women? Ultimately, the coupled correlation between beautiful women and hypermasculine men might lead to modifier genes arising which would slowly dampen and eliminate any negative fitness implications of such matings (that is, the offspring being less fit than either parent because of additive effects resulting in population basal levels of testosterone or estrogen).

I don't offer any of these ideas seriously. They are speculations, but, the overall point is to be open to various explanations and remember that there are multiple paths to a given fitness peak. Over time I have become reluctant to post much about human psychology and its intersection with biology precisely because the popular press tends to take one research paper and take its model at face value, and then proceeds to blow out of proportion the importance of the factor which they pinpoint as explaining variation. I hope readers of this weblog have learned to be cautious and consider looking at the original paper that these stories are based on, that will allow one to take the step beyond entertainment and toward genuine analysis. Also, knowing a little genetic logic can add to both entertainment and analysis.

Update: Through the rugged roads of gene land.

Vincent Gallo offers to sell his sperm   posted by TangoMan @ 11/04/2005 01:37:00 AM

Vincent Gallo, apparently unaware of the fact that guys are giving their sperm away for free, is offering to sell his seed for $1,000,000. He provides the details on his website:

If the purchaser of the sperm chooses the option of natural insemination, there is an additional charge of $500,000. However, if after being presented detailed photographs of the purchaser, Mr. Gallo may be willing to waive the natural insemination fee and charge only for the sperm itself. . . .If you have seen The Brown Bunny, you know the potential size of the genitals if it's a boy. (8 inches if he's like his father.) I don't know exactly how a well hung father can enhance the physical makeup of a female baby, but it can't hurt. . . .Mr. Gallo maintains the right to refuse sale of his sperm to those of extremely dark complexions. . . .Under the laws of the Jewish faith, a Jewish mother would qualify a baby to be deemed a member of the Jewish religion. This would be added incentive for Mr. Gallo to sell his sperm to a Jew mother, his reasoning being with the slim chance that his child moved into the profession of motion picture acting or became a musical performer, this connection to the Jewish faith would guarantee his offspring a better chance at good reviews and maybe even a prize at the Sundance Film Festival or an Oscar.

Well, that sure sounds appealing, doesn't it? Gallo seems to have cornered the market on eccentric sperm, so perhaps if Jodie Foster is in the market for something other than genius sperm, she can have her people call his people. As for that $500,000 natural insemination offer, maybe Deuce Bigolow can give him some tips on the man-whoring business.

Thursday, November 03, 2005

A Cornucopia of New Intelligence Research   posted by Jason Malloy @ 11/03/2005 07:14:00 AM

Via my co-blogger and pro psychologist, Alex, I learn that the International Society for Intelligence Research is holding its 6th annual conference this December in Albuquerque, New Mexico, and by the looks of it, some very interesting research will be presented. Scientists exploring this important, difficult, controversial concept known as intelligence from many different disciplines and research paradigms - differential psychology, economics, sociology, neuroscience, evolutionary biology, paleoneurology, cognitive psychology, evolutionary psychology, artificial intelligence, genetics, animal cognition - are increasingly working together and combining their discoveries to powerful theoretical and empirical effect. For those interested, a PDF is available here with about 50 new abstracts for almost 60 presentations. Below the fold is a summary of the ones that I find the most interesting sorted by subject.

The Flynn Effect

Probably the most puzzling issue in psychometrics today is the Flynn Effect - the phenomenon of obsolete test norms as IQ scores continue to rise. The effect has caused problems or has had uncertain implications for any number of psychometric issues, including the authenticity of the rise itself, the black-white test score gap, the stability of intelligence with age, the effect of adoption studies, the actual IQ of the earlier generations of Asian Americans, and the existence of dysgenic trends.

Alexander Beaujean and Steven J. Osterlind follow recent reports of the Flynn Effect finally stopping, and even reversing, in Europe (see Alex's post here) in a presentation called Assessing the Lynn-Flynn Effect in the College Basic Academic Subjects Examination (Alex and David Burbridge have previously debated the nomenclature of the rise on GNXP here). Alex finds evidence, using special methods of test analysis based on Item response theory, that the Flynn Effect has started to reverse course in America as well.

And Jelte Wicherts, in Flynn Effect in the Woodcock-Johnson Cognitive Ability and Achievement Tests 1976-1999, uses Structural equation modeling techniques to explore whether Flynn gains have been an artificial score inflation (as Alex and I believe) or genuine gains in ability. Equally important, Wicherts attempts to explore whether the FE occurs between cohorts or to everybody at time of measurement (i.e. if you took an IQ test when you were 30, 40, and 50 would it be higher at each successive age (time of measurement), or would it remain stable for individuals across their lifespan, but three brothers age 6, 10, and 15 would be progressively stupider (cohort). Which one it is has meaningful implications for what's causing the rise (e.g. heterosis - a genetic cause - is only consistent with cohort). Previous evidence, such as the stability of IQ across 50+ year longitudinal studies, seem to falsify the TOM model.

On a related issue, Jan te Nijenhuis, et al. look into another area that might be plagued by "hollow" or fake IQ gains. IQ scores go up after retesting and through training programs. In Score Gains on g-Loaded Tests: No g the team demonstrate that these kinds of IQ boosts are not on the g factor (the business end of IQ), and suggest their results have implications for experiments that show schooling increases IQ. These increases may well be hollow.

Measurement and Mental Chronometry

One way to maybe better overcome this problem of "fake IQ gains" is getting at the underlying physical reality of intelligence. For instance, to determine if intelligence gains were "real" or not, we could measure the areas, tissues or structures of the brain that indicate intelligence or monitor more primal functions, such as things like how quickly or efficiently the brain registers simple stimuli through brain waves or glucose metabolism during problem solving. Issues of test bias and the potential of artifactual test gain would no longer be a problem because we could just clock the brain itself. Simple, more accurate, more efficient intelligence measurement is desirable and was Francis Galton's original vision for intelligence testing that ultimately lost out to Binet's measurement method.

One researcher who has helped revive Galton's model is Joseph Fagan, through his work with infants and young children. Habituation is a method for determining what’s going on in the heads' of infants less than one year old. By monitoring a baby's time spent discriminating stimuli, cognitive psychologists have determined innate or early notions of number and causality, evolutionary psychologists have determined culturally neutral standards of beauty and sex differences in social and object interests, and differential psychologists have tracked intelligence differences to the earliest months of life. In The Prediction, from Infancy, of Adult IQ and Achievement, Fagan et al. find that the correlation between the IQs of a sample of 20 year olds and their intelligence measured before the age of 1 is about .60. This is similar to earlier studies, which found the correlation between age 1 and age 11 was about .50.

Moving to the brain itself, a number of presentations come from Richard Haier and Rex Jung. Along with lead author Richard Colom in Correlated Vectors, g, and Gray Matter: A Frontal-Parietal Network and the Einstein Hypothesis they test the theory (named for the enhancement of this particular region in its namesake), through a number of lines of evidence, that the frontal-parietal network is key to individual differences in intelligence. They also review the current regions and structures of the brain known to be associated with intelligence.

Jung et al. also turn to the neurochemistry of intelligence in Biochemical Markers of Individual Differences in Cognitive Functioning, and "highlight the importance of white matter structural and chemical integrity to intellectual performance” which supports "the "neural efficiency" hypothesis that suggests optimal brain organization underlying individual differences in cognitive processes".

Finally, in Investigating the Cortical Temporal Dynamics of the Speed-Intelligence Relationship Using Magnetoencephalography (MEG), Robert Thoma uses MEGs to monitor the activity of the brain, to show that the regions involved in reaction time (RT) experiments (how quickly you lift your finger off a panel to turn off a light) are the same areas that show activity during complex intellectual tasks, suggesting RT is a simple and accurate measure of intelligence (something disputed by NJ Mackintosh in IQ and Human Intelligence, where it is argued that RT is a very nongeneralizable mental ability, not the same as g).

Group Differences

Those interested in HBD will not be disappointed, there are a number of presentations on race and sex differences, including a biggie from Greg Cochran and Henry Harpending titled The Evolutionary Biology of Human IQ Diversity: Some Current Directions and Hints. Fresh from their Ashkenazi notoriety, they discuss the far more contentious issue of Eurasian intelligence, with a new theory that fingers the Neanderthals!:
Modern humans apparently left Africa ca. 40,000 years ago and appeared soon afterwards in western Eurasia and in Australia. The southern arm peoples arrived with middle Paleolithic technology that persisted unchanged for tens of millenia while the northern arm peoples were host to the famous "creative explosion" of the upper Paleolithic with elaborate tools, worked bone, beadword and other adornment, sculpture, and painting. We discuss the hypothesis that incorporation of Neanderthal genes led to elevated intelligence (or something closely related) in the northern arm. We will mention some likely examples of such assimilated genes . . . We discuss the appearance and spread of an ASPM variant, one of the microcephalin complex genes, as an example. A puzzling pattern among candidate genes for elevating IQ is that they seem not to have spread in Africa

Additionally, two more talks add to and work off of Lynn and Vanhanen's Important book. In IQ & Wealth of Nations: Prediction of National Wealth, Deborah Whetzel and Michael McDaniel replicate Lynn and Vanhanen's findings and also find that education spending per student provides no incremental prediction of GDP beyond IQ. They examine a set of the highest predictors of GDP and find that economic freedom, health spending per capita and IQ explain 90% of the variance in national wealth (See also the Jones & Schneider paper and Garett Jones' newer paper (PDF)). Earl Hunt and Werner Wittmann also replicate Lynn and Vanhanen's finding in Relations Between National Intelligence and Indicators of National Prosperity, and add to it by examining cross-national student scholastic achievement from international datasets like PISA and TIMSS. They find a strong relationship between intellectual competence and economic indicators. In Criteria For Studies of Race and Intelligence, Earl Hunt also makes the case for agnosticism about genetics being the source of these (real and important) differences, with discussion of research ethics and study design for racial behavior genetics.

In Race Difference in General Intelligence g in Relation to Blood Pressure, Body Proportions, Hormones, and Personality, Helmuth Nyborg et al. test and reject another theory for the black-white IQ gap - that greater black hypertension plays a role in the difference.

Of course these kind of theories are DOA. The real problem is how to test the factor X theory, that the black-white IQ gap is due to something unique to the black environment that affects all blacks equally but is completely absent from the white environment in a way that could evade all detection thus far. A team of researchers published a paper (PDF) in 2003 responding to the well known argument that high within-group white and black heritability has no implications for their between-group IQ difference, showing that a common factor model "approach clarifies that absence of measurement bias implies common sources of within- and between-group variation" (earlier, the late David Rowe similarly showed, through an ingenious method of structural equation models using blacks and whites and their full and half siblings, that the source of the within group differences was also causing the between group difference). In Factorial Invariance and the Representation of Within-Groups and Between-Groups Differences: A Reconsideration Keith Widaman disputes their argument, but offers his own methods "for study design that will enable a test of the hypothesis that sources of within-group differences are also responsible for between-group differences".

On the sex difference front, Paul Irwing presents Sex Differences in General Cognitive Ability: A Reexamination of the Evidence, which seeks to question whether the 100 year old position in psychometrics - that there is no mean difference between men and women on IQ - is correct (as Jensen also concluded in 1998's The g Factor), or whether Richard Lynn's newer (1990>) position - that men have somewhat higher average IQs - is correct. Irwing concludes from large SPM samples that Lynn is correct (as was reported in the media a few months ago). Furthermore, he finds no evidence that this is due primarily to the male advantage in spatial visualization. Also, he finds that some research previously presented to show that there are no sex differences shows exactly the opposite.

David Puts et al. also present a meta-analysis titled Possible Organizational Effects of Early Androgens on Human Spatial Ability: Meta-Analyses of CAH and Digit Ratio Studies Showing that females that get a heavy dose of male hormones in utero also perform higher on spatial tasks like men do.


David Puts' finding has implications for the ridiculous Larry Summers' witch-hunt earlier this year as well. Rose Mary Webb et al. study the geniuses among us in Spatial Ability: A Neglected Dimension in Talent Searches for Intellectually Precocious Youth, and find using longitudinal data that children with high spatial abilities (who - a la Puts - are going to be disproportionately male) have higher levels of interest in math and science ("theoretical" endeavors) and that the ability can be used to predict which gifted students follow scientific or humanities pathways. Similarly, Summers' critics have tried to rebuff the annoying fact that many more men score at the top of the ability distribution by asserting that IQ/test score ability stops being meaningful at the higher levels of ability anyway (that is, conveniently, at the precise point where the male/female ratio starts to get ridiculously incongruous. e.g. 7 to 1 in the top 1%). In Creative Accomplishments Covary With Ability Even Among the Top 1%, Jonathan Wai et al. show this is nonsense; IQ keeps discriminating between levels of creative and career achievement (such as earning a math-science PhD, securing a patent, and achieving tenure at a top 50 U.S. university), even at the very skinny right tail of the ability distribution. (and it keeps on going: IQ even distinguishes those in the top .0001%!)

Two additional presentations on those at the right tail, An Examination of Spearman's Law of Diminishing Returns by Christopher Condon and David Schroeder and A Test of Spearman's Law of Diminishing Returns in the Kaufman Assessment Battery for Children, Second Edition by Matthew Reynolds and Timothy Keith, test Spearmen's idea that the g factor is more important at low IQ levels, and that lower order factors are more independent and important at progressively higher ability levels. Using different data sets both studies find support for this. "Multiple intelligences" (and not the fictional Gardner ones) are only something for the very smart, for people at the left tail it's all about g.

The Evolution of Human Intelligence

A number of presentations attempt to tie general intelligence into the framework of human evolution. James Lee's The Evolution of General Intelligence in the Primate Clade, for instance, talks about research showing that mental testing across primate genre best distinguishes them by a single general factor (see also the latest issue of Behavior Genetics for a detailed exploration of the g factor in mice). The correlation between brain size and the g factor across 25 primate genre is .77. Lee discusses this in the context of Bruce Lahn's recent papers.

David C. Geary uses material from his fascinating new book in The Origin of Mind: Evolution of Brain, Cognition, and General Intelligence. Geary argues that "The primary dynamic that has driven and is currently driving human evolution is competition with other people and groups of other people for resource control" and that intelligence involves the ability to form more accurate "mental models" of the outside world, and that the systems to build these models "are known as general fluid intelligence, working memory, and attentional control" and that "The combination of these systems and folk knowledge is the foundation upon which human intellectual and cultural advances have been built".

In contrast to Geary, Linda Gottfredson argues in Innovation, Fatal Accidents, and the Evolution of General Intelligence that competition with other people hasn't been the primary engine of human intellectual evolution, but instead that each boost in intelligence led to new technologies which created new dangers that continuously pruned off those at the bottom of the spectrum. Innovation then would boost IQs through increased selection, which would thus lead to even more innovation, and the cycle fuels itself. (her paper, by the way, is one of the few that can already be found online. Here (PDF).

Kim Hill presents The Adaptive Function of High Cognitive Ability in Hunter-Gatherers: Feeding Niche or Social Complexity?, where an IQ study of modern hunter-gatherers is discussed. In support of David Geary and the modern consensus of "Machiavellian intelligence", it was found that higher IQs in this group were associated with higher social status. Contradicting the old "Man the Hunter" theory of intelligence, Hill reports that there was no association between hunting prowess and measured intelligence.

In Mutual Mate Choice for Intelligence as a Fitness Indicator, Geoffrey Miller uses research from evolutionary psychology to support his theory that sexual selection was responsible for driving up human intelligence. And in a related lecture, Intelligence and Mate Choice, Mark Prokosch explores the assumptions behind the sexual selection theory (e.g. how important is intelligence in long and short term mates? How accurately do females judge intelligence?) and tests some of them directly.


A number of other presentations deal with the issue of "Emotional Intelligence" (empty) and "Life History Theory" (all the presented papers fail to support it). I do not find those issues interesting, but the abstracts are in there for you. A few more deal with technical issues, such as test refinement, which are no doubt important to the field but less fun to talk about. The last one I'll leave you with, though, might be of interest if you've ever had the misfortune to encounter Internet ads, and says all it needs to just in the title: Web-Based IQ Tests: A Concept Whose Time Has Not Yet Come.


Wednesday, November 02, 2005

Hotties gotz hormones....   posted by Razib @ 11/02/2005 11:03:00 PM

This paper, Facial appearance is a cue to oestrogen levels in women, is getting a lot of press right now. This tells us nothing new, there have been many, many, studies which show that there is a positive correlation between elevated estrogen levels and feminine (i.e., attractive) features. But check out the photos, isn't it striking how shaving a millimeter here and there can change things?

Update: The Royal Society has dynamically generated links from what I can should be fixed now.

The Sacral State   posted by Razib @ 11/02/2005 09:50:00 PM

Ross Douthat of The American Scene linked to my post A Prayer for Emperor, which was a reflection on the book The Impossibility of Religious Freedom. Unfortunately, the same confusion as to my intent keeps coming up: people seem to assume that I meant the title to literally suggest that the deification of the head of state was imminent. I sure as hell need to be more careful about titles! Of course, I was stupid in that I realize in hindsight that I have a particular understanding of the religio-political culture of the Roman state which others might not share, and I'm not too inclined on decomposing my thoughts on that now, or in the future (and I doubt any of you are inclined to read those thoughts if I did divulge them!). So, I thought I should restate what I actually meant. Consider a trichotomy.

  1. The "classic" church-state separation model which was dominant from the mid-19th century until the present day in the United States. In this situation, the various religious groups have commonalities, and a minimal "civil religion" is the norm which is accepted in public life. The dominant religions tend to emphasize creeds (beliefs) and prosaic and sacrally marginal forms of worship. Ornate rituals, liturgies and precise religio-legal injunctions are a minimal part of the range of religious practice.
  2. The established exclusive church model, which one can see in many parts of the Islamic world, and was once the norm in the Western world (roughly from Theodosius I until Westphalia). In this system even if there is a range of belief and folk practice, the public ritual space is monopolized forcefully by one religious group. All other groups lack state legitimacy.
  3. The established "loose" church model. A various times during the Roman Empire different cults were dominant in the public space. For example, the emperor Vespasian was a devotee of Isis. In the 3rd century various solar deities were ascendent. In the early to mid 4th century Christianity was dominant. But, this did not render all other cults illegitimate, nor did it exclude them from the public space. Note that Constantine's sons all held (ceremonially) titles which implied that they were the heads of traditional pagan state cults, even though they were Christian by profession and unbringing. It was only late in the 4th century that exclusive Christianity banished all other religious expression from the commanding heights of culture and the public fora (the last public elite pagan revival was quashed in 395).
I do not think there is any possibility that the United States can revert to #2. Ross makes a cogent point in terms of the mobilization of religion for politics theological illiteracy removes barriers of suspicion between groups of similar social persuasions. Nevertheless, politics is not religion in the end. #1 is problematic because religious pluralism has introduced traditions which emphasize form, practice and ritual to a far greater extent than Protestant denominations which have taken refuge under the 1st ammendment. Accommodating alternative belief is relatively painless, and banishing creedal recitations from the classroom is logically tenable. Accommodating every single expression of religious belief, practice and custom in the workplace, in schools or in public spaces is impossible. Even accommodating a moderate level of diversity might tax the system. For example, in the interests of religious equality shall we continue to add state sanctioned holidays to the current list?

Ultimately the state needs to favor some values. Where the line is drawn is up to the state, and the people. If the line is biased toward expansive accommodation, then it will extend the logic of #1 into other dimensions (i.e., beyond belief and the bare basics of neutrality in regards to funds and services). If on the other hand the state begins to favor a particular set of beliefs, then I suspect we will see #3, not #2. Instead of a Roman analogy, consider the Anglican church at the turn of the 20th century. Dissenters and Roman Catholicism (as well as Spiritualism, agnosticism, etc.) were all accepted as options within the culture, but Anglicanism was the elite and government norm. Today, that tradition continues de jure, though it has little force or implication. I suppose the next question would be: what religion would the future America choose? I'll take that on in the future....

Minor notes   posted by Razib @ 11/02/2005 04:51:00 PM

For some time now I've been telling people that John Hawks is making other evobloggers look bad. Frankly, I am tempted to link to every other post over on his weblog. Well, I won't be linking to his posts unless there is a non-trivial amount of commentary from this moment on, look to the right and you will notice that I am now displaying his RSS feed (Update: scripts are having issues, so I turned the feeds off for now).

On another matter, the dynamic duo have another paper out, Genetic diversity and genetic burden in humans.

Additionally, I'm noticing an uptick in people buying books, probably for the X-mas season. Remember that GNXP is an Amazon Associate, so if you go through our site to buy something we get a cut. Last X-mas someone bought a computer!

Finally, people often email me links to papers. I really appreciate that, but, if you wouldn't mind, you might also "cc" your find into the gnxp forum. I don't have time to comment on or link to every submission, but a lot of the papers are interesting. You might find something else of interest in the forum in the process.

Tuesday, November 01, 2005

Problems with HapMap   posted by Razib @ 11/01/2005 01:27:00 AM

Please see John's post.