When Mendelism reemerged in the early 20th century to become what we term genetics no doubt the early practitioners of the nascent field would have been surprised to see where it went. The centrality of of DNA as the substrate which encodes genetic information in the 1950s opened up molecular biology and led to the biophysical strain which remains prominent in genetics. Later, in the 1970s Alan Wilson and Vincent Sarich used crude measures of genetic distance to resolve controversies in paleontology, specifically, the date of separation between the human and ape lineage. Genetics spans the physical and historical sciences, whereas physically oriented scientists may look to DNA as a basis for computation, historically oriented scholars can use it to illuminate mysteries in their own fields.
In the 1980s the “mitochondrial Eve” arrived on the scene, purporting to map out the demographic history of our species over the past 200,000 years. This was during an era when extraction and amplification of genetic material was primitive, and so the numerous mitochondria were the preferred sources of information. Additionally, the uniparental nature of mtDNA makes it ideal for a coalescent model.
Over the past two decades science has come much farther. Genetic material is easier to analyze, and the computers to do that analysis have become much more powerful. A non-trivial segment of the genome is now being brought to bear on questions of genetic history. More powerful computational techniques mean that the complexity of the models can be cranked up. This is evident in a recent paper, Inferring the Joint Demographic History of Multiple Populations from Multidimensional SNP Frequency Data:

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The other day I saw a flier for a colloquium in my department that sounded kind of interesting, but I thought “It probably won’t be worth it,” and I ended up not going. After all, anyone with an internet connection can find a cyber-colloquium to participate in — and drawn from a much wider range of topics (and so, one that’s more likely to really grab your interest), whose participants are drawn from a much wider range of people (and so, where you’re more likely to find experts on the topic — although also more know-nothings who follow crowds for the attention), and whose lines of thought can extend for much longer than an hour or so without fatiguing the participants.

So, this is something like the Pavarotti Effect of greater global connectedness: local opera singers are going to go out of business because consumers would rather listen to a CD of Pavarotti. It’s only after it becomes cheap to find the Pavarottis and distribute their work on a global scale that this type of “creative destruction” will happen. Similarly, if in order to get whatever colloquia gave them, academics migrated to email discussion groups or — god help you — even a blog, a far smaller number of speakers will be in demand. Why spend an hour of your time reading and commenting on the ideas of someone you see as a mediocre thinker when you could read and comment on someone you see as a superstar?

Sure, perceptions differ among the audience, so you could find two sustained online discussions that stood at opposite ends of an ideological spectrum — say, biologists who want to see much more vs. much less fancy math enter the field. That will prevent one speaker from getting all the attention. But even here, there would be a small number of superstars within each camp, and most of the little guys who could’ve given a talk here or there before would not get their voices heard on the global stage. Just like the lousy local coffee shops that get displaced by Starbucks — unlike the good locals that are robust to invasion — they’d have to cater to a niche audience that preferred quirkiness over quality.

So the big losers would be the producers of lower-quality ideas, and the winners would be the producers of higher-quality ideas as well as just about all consumers. Academics wear both of these hats, but many online discussion participants might only sit in and comment rather than give talks themselves. It seems more or less like a no-brainer, but will things actually unfold as above? I still have some doubts.

The main assumption behind Schumpeter’s notion of creative destruction is that the firms are competing and can either profit or get wiped out. If you find some fundamentally new and better way of doing something, you’ll replace the old way, just as the car replaced the horse and buggy. If academic departments faced these pressures, the ones who made better decisions about whether to host colloquia or not would grow, while those who made poorer decisions would go under. But in general departments aren’t going to go out of business — no matter how low they may fall in prestige or intellectual output, relative to other departments, they’ll still get funded by their university and other private and public sources. They have little incentive to ask whether it’s a good use of money, time, and effort to host colloquia in general or even particular talks, and so these mostly pointless things can continue indefinitely.

Do the people involved with colloquia already realize how mostly pointless they are? I think so. If the department leaders perceived an expected net benefit, then attendance would be mandatory — at least partial attendance, like attending a certain percent of all hosted during a semester. You’d be free to allocate your partial attendance however you wanted, just like you’re free to choose your elective courses when you’re getting your degrees — but you’d still have to take something. The way things are now, it’s as though the department head told its students, “We have several of these things called elective classes, and you’re encouraged to take as few or as many as you want, but you don’t actually have to.” Not exactly a ringing endorsement.

You might counter that the department heads simply value making these choices entirely voluntary, rather than browbeat students and professors into attending. But again, mandatory courses and course loads contradict this in the case of students, and all manner of mandatory career enhancement activities contradict this in the case of professors (strangely, “faculty meetings” are rarely voluntary). Since they happily issue requirements elsewhere, it’s hard to avoid the conclusion that even they don’t see much point in sitting in on a colloquium. As they must know from first-hand experience, it’s a better use of your time to join a discussion online or through email.

The fact that colloquia are voluntary gives hope that, even though many may persist in wasting their time, others will be freed up to more effectively communicate on some topic. Think of how dismal the intellectual output was before the printing press made setting down and ingesting ideas cheaper, and before strong modern states made postage routes safer and thus cheaper to transmit ideas. You could only feed at the idea-trough of whoever happened to be physically near you, and you could only get feedback on your own ideas from whoever was nearby. Even if you were at a “good school” for what you did, that couldn’t have substituted for interacting with the cream of the crop from across the globe. Now, you’re easily able to break free from local mediocrity — hey, they probably see you the same way! — and find much better relationships online.

If you haven’t been following the goings-on via Twitter, Luke Jostins has been posting some tidbits on his blog, Genetic Inference. If you get interested in something, remember you can search abstracts.

Enhanced Edar Signalling Has Pleiotropic Effects on Craniofacial and Cutaneous Glands:

The skin carries a number of appendages, including hair follicles and a range of glands, which develop under the influence of EDAR signalling. A gain of function allele of EDAR is found at high frequency in human populations of East Asia, with genetic evidence suggesting recent positive selection at this locus. The derived EDAR allele, estimated to have reached fixation more than 10,000 years ago, causes thickening of hair fibres, but the full spectrum of phenotypic changes induced by this allele is unknown. We have examined the changes in glandular structure caused by elevation of Edar signalling in a transgenic mouse model. We find that sebaceous and Meibomian glands are enlarged and that salivary and mammary glands are more elaborately branched with increased Edar activity, while the morphology of eccrine sweat and tracheal submucosal glands appears to be unaffected. Similar changes to gland sizes and structures may occur in human populations carrying the derived East Asian EDAR allele. As this allele attained high frequency in an environment that was notably cold and dry, increased glandular secretions could represent a trait that was positively selected to achieve increased lubrication and reduced evaporation from exposed facial structures and upper airways.

Every explanation for the “classic Mongoloid” phenotype seems to go back to “cold and dry.” Some things never change.

If you haven’t been following the goings-on via Twitter, Luke Jostins has been posting some tidbits on his blog, Genetic Inference. If you get interested in something, remember you can search abstracts.

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Very interesting paper in PLoS Genetics, Inferring the Joint Demographic History of Multiple Populations from Multidimensional SNP Frequency Data. Here’s the author summary:

The demographic history of our species is reflected in patterns of genetic variation within and among populations. We developed an efficient method for calculating the expected distribution of genetic variation, given a demographic model including such events as population size changes, population splits and joins, and migration. We applied our approach to publicly available human sequencing data, searching for models that best reproduce the observed patterns. Our joint analysis of data from African, European, and Asian populations yielded new dates for when these populations diverged. In particular, we found that African and Eurasian populations diverged around 100,000 years ago. This is earlier than other genetic studies suggest, because our model includes the effects of migration, which we found to be important for reproducing observed patterns of variation in the data. We also analyzed data from European, Asian, and Mexican populations to model the peopling of the Americas. Here, we find no evidence for recurrent migration after East Asian and Native American populations diverged. Our methods are not limited to studying humans, and we hope that future sequencing projects will offer more insights into the history of both our own species and others.

And from the abstract:

We infer divergence between West African and Eurasian populations 140 thousand years ago (95% confidence interval: 40-270 kya). This is earlier than other genetic studies, in part because we incorporate migration. We estimate the European (CEU) and East Asian (CHB) divergence time to be 23 kya (95% c.i.: 17-43 kya), long after archeological evidence places modern humans in Europe. Finally, we estimate divergence between East Asians (CHB) and Mexican-Americans (MXL) of 22 kya (95% c.i.: 16.3-26.9 kya), and our analysis yields no evidence for subsequent migration.

I would keep in mind these 95% confidence intervals, but I immediately wondered about this European-East Asian divergence time just like Dienekes.

After I hit “post” for the entry below, cheering linguistic uniformity, I realized that perhaps a word should be said about the obvious downsides. Large populations are probably a spur to innovation as the raw number of individuals of the smart fraction reaches critical mass. But denser populations also gave rise to numerous infectious diseases. Travel is a boon to communication, but it also spreads disease. The larger the population, and the more interconnected the populations, the more opportunities open up for pathogens. Similarly, despite the gains from global trade and common capital markets it also generates synchronous business cycles (and, perhaps exacerbates volatility). Good things usually have downsides. And so it would be with the rise of linguistic uniformity: a demagogue who could communicate with clarity, and subtle allusive power, to billions, would be enabled.

In Chinatown, Sound of the Future Is Mandarin:

He grew up playing in the narrow, crowded streets of Manhattan’s Chinatown. He has lived and worked there for all his 61 years. But as Wee Wong walks the neighborhood these days, he cannot understand half the Chinese conversations he hears.

Cantonese, a dialect from southern China that has dominated the Chinatowns of North America for decades, is being rapidly swept aside by Mandarin, the national language of China and the lingua franca of most of the latest Chinese immigrants.

It’s more complicated than that, as the article notes that Cantonese replaced the closely related dialect of Taishanese. Another interesting twist is that the new wave of migrants are themselves not necessarily native speakers of a Mandarin dialect as they are generally from Fujian. Rather, Standard Mandarin is a lingua franca among common people in the Chinese world now in a manner it may not have been when the earlier waves of South Chinese arrived in the United States. In Singapore and Taiwan the Chinese also derive from various regions of Fujian, but Mandarin is an official language, and the monolingualism in dialects is only common among the old.

This is just a specific case of a general dynamic; French, German and Italian all replaced numerous regional dialects, some of which still retain local vitality. Just as Taiwan’s predominantly Fujianese population accepts Standard Mandarin, so Switzerland’s dialect speaking population accepts Standard German as the official public face of the language (no matter that privately they may converse in Swiss German).

Though linguists and anthropologists bemoan the decline of diversity and local flavor, when it comes to communication this is probably a good thing for the individuals and the societies in which they live. Not only is language often a divisive fault line, but it serves as a barrier to the exchange of ideas and socialization. Whatever marginal cognitive benefits are accrued to individuals who learn multiple languages, on the balance uniformity of speech opens up many possibilities of coordinated action. Even the ancients knew that.

Note: Of course with the dying of a language with a large body of literature some aspect of immediate comprehension and memory of the past vanishes. When it comes to dialect traditions I obviously weight the loss of collective memory less because I tend to perceive oral cultures as encoding cross-cultural values by and large. There may be a thousand twists on the tale of the “Trickster god,” but moral of the story is rather the same. In any case, when the last native speaker of Sumerian died no doubt there was a subtle shift in perceptions of the story of Gilgamesh, but I think such losses are a small cost to pay for mutual intelligibility.

Addendum: According to Peter Brown in The Rise of Western Christendom the shift from Syraic dialects to Arabic among the Christian populations of the Levant and Mesopotamia was the tipping point in terms of conversion to Islam. So from some perspectives unintelligibility and separation of language are beneficial. Consider Hasidic Jews and Amish who have long been resident in the United States but continue to speak dialects of German amongst themselves (in my experience the Amish speak English without any accent except for a somewhat quaint aspect, but I have read and heard Hasidic Jews who speak English with a very strong accent which indicates they learned the language in their later teens at the earliest).

I’ve pointed out before that the most (reputedly) secular Muslim majority country, Turkey, is more friendly to Creationism and more religious than the United States. This is why I get really agitated by those who argue that Turkey should join the European Union, it isn’t culturally appropriate. Europeans might be prejudiced against Turks because they’re “oriental” (in the old sense) and Muslim, but that doesn’t mean that Turks are just like any European in values. Liberal elites terrified of seeming prejudiced and Eurocentric don’t want to acknowledge this generality of difference, but it is important to point out specific cultural shibboleths and markers which even they’ll have a reflexive response to. For example, Meet Harun Yahya: The leading creationist in the Muslim world:

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