If you find the material on this blog of interest, I highly recommend that you subscribe to Jason Malloy’s de facto clipping service: http://tech.groups.yahoo.com/group/gnxpforum/. A far number of the articles I blog about I find via that entry on my RSS….

Check out a long piece on bonobos in The New Yorker. Now, I’ve read a fair amount of Frans de Waal’s work, and I think the piece is making him out to be a little more PC than he is. Nevertheless, I am a bit disturbed by the fact that hasn’t seen a Bonobo in the wild! I just happened to have missed that assumed that though most of his research was based on captive animals, there must have been some field research supplementing it. No. And de Waal’s response it pretty lame:

Captivity can have a striking impact on animal behavior. As Craig Stanford, a primatologist at the University of Southern California, recently put it, “Stuck together, bored out of their minds–what is there to do except eat and have sex?” De Waal has argued that, even if captive bonobo behavior is somewhat skewed, it can still be usefully contrasted with the behavior of captive chimpanzees; he has even written that “only captive studies control for environmental conditions and thereby provide conclusive data on interspecific differences.” Stanford’s reply is that “different animals respond very differently to captivity.”

Frans has to know about the problems that might occur because of a norm of reaction. Environments don’t always have the same linear effect on phenotype as you vary them across different genotypes. Bonobos are complex creatures, just like humans. Just as controlled psychological studies on colleges students are important in smoking out the nature of our own species’ cognitive apparatus, field work by anthropologists is also essential in documenting the extent of variation of behavior in the “wild.” It see no reason why the same principle wouldn’t apply to great apes, even if to a lesser extent.
Update: Here’s an interview with a Bonoboologist.

Self-centered cultures narrow your viewpoint:

Chinese students would immediately understand which wooden block to move – the one visible to both them and the director. Their US counterparts, however, did not always catch on.

“They would ask ‘Which block?’ or ‘You mean the one on the right?”, explains Keysar. “For me it was really stunning because all of the information is there. You don’t need to ask,” he adds.

While 65% of the American participants asked this type of question, only one of the 20 Chinese subjects did so, equating to just 5%.

This comes close to the classic “they did a study on that?” criticism of psychology. Of course we know that East Asians cultures emphasize a contextual perception of self and collectivist values vis-a-vis Western ones. But, it is nice to get a quantitative sense of the extent of this difference. You can read the full paper on the author’s website. Here is an important point:

In fact, language can trigger a culture – bound representation of self…bicultural Chinese-born individuals tended to describe themselves in terms of their own attributes when writing in English, but to describe themselves in relation to other people when writing in Chinese.

This shouldn’t surprise you if you read Geography of Thought. It seems people can be easily “trained” to change their vantage points (casting some light on the grand claims made by the author in the aforementioned book). The facultative nature of these extreme differences seems pretty obvious; especially given that extreme individualism manifest in English speaking peoples in particular, while continental Europeans tend to lay between the East Asian collectivism and Anglo-Saxon collectivism despite their far closer genetic affinity to the latter. Nevertheless, though the extremity of the differences in operation of Theory of Mind here is likely cultural, I can not be suspect that there might small, but significant, initial differences between populations. After all, Jerome Kagan has shown that personality differences exist between Asian and European infants at very young ages, as well as between blue-eyed and brown-eyed children (in both cases the former tend to be more withdrawn and inhibited than the latter). The question that comes to my mind is whether the cultural differences selected for different personality profiles, or whether there were initially difference personality profiles which resulted in different cultural outcomes. My own suspicion in the East Asian case is the former.

I was putting off commenting on this, and wondering whether I had any value to add. But a reader pointed me to Noah Feldman’s Orthodox paradox, a piece in The New York Times Magazine where the author, a young Harvard law professor, reflects on his journey from the Modern Orthodox subculture into the wider world. The whole piece is worth reading. There is a problem in these sorts of articles insofar as Feldman is such an “insider,” while most of the readers are such “outsiders,” that one is totally dependent on the author for context and situation. For example, most gentiles have difficultly distinguishing between Reconstructionist, Reform, Conservative and Orthodox movements in the United States, let along the distinction between Modern Orthodoxy, and less modern Orthodox movements, the latter of whom are divided between the Hasidic and non-Hasidic. My own impression is that there isn’t a hard & fast line between Modern Orthodox and non-Modern Orthodox. I’ve had friends who call themselves “Conservadox,” and it is no surprise that the Conservative movement has had problems because of this broad scope. To illustrate this I know someone whose Conservative synagogue became a Reconstructionist synagogue, which might seem strange when you know that on the spectrum of religious ideals Reform probably sits somewhere in the middle between Conservative and Reconstructionism. But historically Reconstructionism emerged out of the Conservative movement, not the Reform one, so that makes the jump a bit more intelligible. In any case, the point is that though Feldman’s piece has broad and general relevance to the human condition, there are precise contextual details and differences of interpretation in regards to his narrative which are probably important to keep in mind before making sweeping generalizations.

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A Hunk’s Dental Downfall:

When males and females were about the same size, so were their teeth. But in species in which larger males evolved, tooth size increased relatively little. Thus, females ended up with larger chewing surfaces for their size than did males, the researchers report in the September issue of American Naturalist. The team concludes that teeth probably didn’t grow at the same rate as body size because males can successfully compete for females only in their prime. Once teeth wear down, they become ineffective, and the animal gets weaker and more susceptible to disease or injury. But that doesn’t matter to these males, as once they are too old to beat out rivals for mates, there’s no need to live a long life. When it comes to how many offspring a male can father, “it seems that compared to body mass, tooth size is relatively unimportant,” says Joanne Isaac, a mammalogist at James Cook University in Townsville, Australia, who was not part of the study team.

In highly polygynous species males in their prime are the fathers of a multitude. These species’ males enter into a winner-take-all lottery game when it comes to reproduction. It makes sense that these males wouldn’t live that long. It isn’t likely that they could greatly increase the fitness of their numerous offspring through parental investment simply because there might be so many of them. Male investment in humans makes some sense in the case where a typical man may have only a few children who survive to their reproductive years. Nevertheless, there is some reproductive skew within our own species, and the extent of that skew varies from population to population and across historical epochs. The reproductive outcome for the total population may remain the same no matter if it is characterized by a equilibrium of low risk & low yield male strategies, or high risk and high yield strategies, but the dynamics within the society are likely going to be very different. I am not convinced that our current low risk & low yield strategy (i.e., monogamous pair-bonding) isn’t just a metastable situation, highly susceptible to disruption.

Kosik and colleagues used laser capture microdissection to get RNA populations from dendrites or cell bodies of cultured rat neurons. They optimized their technique so that mRNAs known to be enriched in dendrites, such as CaMKII and MAP2, showed about equal levels from soma and dendrite. They then performed multiplex PCR for several mRNAs and 187 miRNAs. The distribution of mRNAs and miRNAs is similar with a large somatic population and a gradient going out into the dendrites. Some small proportion of miRNAs have a little bit of dendritic enrichment. One point the authors are trying to get across is that there is no such thing as a ‘dendritic RNA’ because even the mRNAs and miRNAs that show some dendritic localization usually show just as much in the cell body.

Two nice things are that this paper validates a couple miRNA target prediction programs (Pictar and Targetscan) and that they provide a quantitative view of the miRNA copy number per cell. Both of these prediction programs suggested that miR-26a would target MAP2. This is convenient since both showed a somatodendritic distribution, meaning they hang out together even out at the farthest dendritic reaches. Inhibition of miR-26a with a synthetic oligonucleotide resulted in increases in MAP2 protein expresion, as one would expect from the classic miRNA-target relationship. As far as I am aware this brings the total of known dendrtici miRNA target pairs up to three, the other two being mir-268 and CaMKII (in drosophila) and miR-134 and LIM-Kinase. Quantification was achieved using PCR with known copy number standards. They knew how many cell bodies they captured, so they could get a copy number per cell estimate (probably a minor undershoot since even if they are awesome they probably couldn’t save allllll the RNA from degradation). Anyway, they found… well I’ll let them explain it:

rno-miR-124a is among the most abundant miRNAs in neurons and fell in the range of 10^4 copies per neuronal cell body. Despite its abundance, rno-miR-124a is enriched in cell bodies. rno-miR-26a and rno-miR-16 are less abundant miRNAs and fell in the range of 10^3 copies per neuronal cell body (Table 6). Because (delta)Ct of 2.61 +/- 0.39 describes the distribution of most miRNAs between the cell body and neurite, the number of copies of many miRNAs distributed along this gradient may be as low as in the hundreds of copies in the dendritic compartment. Even a one-order-of-magnitude error in this number is far below the number of synapses on the dendritic tree, and, therefore, the copy numbers of many miRNAs are likely to fall below one per synapse.

Delta Ct refers to the number of PCR cycles (i.e. doublings) it takes for the dendritic levels to reach the somatic levels. For instance, a delta Ct of 2.61 means that there are 2^2.61 (~6.1) times more somatic copies of the miRNA than there are dendritic copies.

I was particularly intrigued by this last sentence even though I have no idea what it means:

Stochasticity derived from the effects of miRNAs will contribute to the activation barrier for coherent responses, to the utilization of information provided by translational bursting, and to the flexibility needed by dendrites to sample alternative states (Kaern et al. 2005).

Guess I’ll have to read Kaern et al. real quick.

Revere has the details.

Update II: John Hawks leaves a comment.
Update: Kambiz has much more comment.
Were neandertal and modern human cranial differences produced by natural selection or genetic drift?:

… Here we use a variety of statistical tests founded on explicit predictions from quantitative- and population-genetic theory to show that genetic drift can explain cranial differences between Neandertals and modern humans. These tests are based on thirty-seven standard cranial measurements from a sample of 2524 modern humans from 30 populations and 20 Neandertal fossils. As a further test, we compare our results for modern human cranial measurements with those for a genetic dataset consisting of 377 microsatellites typed for a sample of 1056 modern humans from 52 populations. We conclude that rather than requiring special adaptive accounts, Neandertal and modern human crania may simply represent two outcomes from a vast space of random evolutionary possibilities.

I am generally skeptical of drift as a catchall explanation (it often serves as a deus ex machina, just as sexual selection has become), but from what little I have gleaned from paleoanthropology it seems that some workers contend that the morphological differences between Neandertals and “modern” humans are overemphasized. I’m thinking here body form, e.g., the short & stocky build typical of Arctic peoples. Obviously the consistent patterns of changes in size and proportion of large mammalian species (larger & stockier the further north) across many taxa point to common selective pressures due to environment; but what about cranium? I simply don’t know. I do know that human bone structure and teeth have become less robust over the last 10,000 years, perhaps due to agriculture. This might simply be relaxing the selection for more robust physiques. I hope John takes a minute from his grant application and comments….

Ali Eteraz points me to the fact that the Grand Mufti of Egypt seems to have offered the opinion that ‘Muslims can choose their own religion’. This is important, because as Wikipedia says:

All five major schools of Islamic jurisprudence agree that a sane male apostate must be executed. A female apostate may be put to death, according to some schools, or imprisoned, according to others.
Some contemporary Shi’a jurists, scholars, writers and Islamic sects have argued or issued fatwas that either the changing of religion is not punishable or is only punishable under restricted circumstances, but these minority opinions have not found broad acceptance among Islamic scholars.

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Most of you could probably guess that my first post on Harun Yahya was meant to highlight what a joke the whole affair was. You see, making fun of Harun Yahya and his fellow travelers is a guiltless pleasure: you get to be snobby and elitist toward those idiotic moronic knuckle-draggers, and, you feel righteous about it because you’re on the side of the angels!. How much of a hilarious incident was this? The first segment of Bloggingheads.tv was devoted to it, and the two pundits, neither of whom had a science background, thought it was pretty sneer and smirk worthy. That’s what I told Ali when he asked me what I thought of the article, basically, I’d been laughing my ass off about how stupid those primitive Muslims were. Now, I know that not all Muslims are primitive let alone stupid. Nevertheless, Harun Yahya & company’s “proofs” about the falsity of evolution were so transparently a product of a sub-standard mentality that it isn’t hard to trigger the atheist schemas which attempt to portray all religious people as barely above apes. Fundamentally, Creationism without sophistry is more of a problem for religious people who value their intellects because it is so nakedly propagandistic to the neutral observer.

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