Sweet selection!!!

I know there's a member of the Sociobiology Study Group under every bed, but I wonder how any of these very interesting papers say anything about the particular complaints with Wade's book.

An ex cathedra "asinine" (which clever rhetorical move you seem a bit too fond of lately) just doesn't cut too much ice.

Yes, I also know that it's politically incorrect around here to cavil at genetic speculation but what, precisely, makes these particular complaints asinine?

Quotes from review in question:

"He also states that stressing genetic racial differences as he does is "objective" and scientific, but stressing human similarities is "political". Wade argues that Europeans resist 'mad cow disease' because their ancestors were selected for cannibalism. He also says that Jews were selected for higher intelligence than other peoples because of the calculational demands of money-lending. He suggests that high intellectual skills are a genetic adaptation that occurred only after the origin of settled societies in places such as Europe. And he says that the Chinese as a "race or ethnic group" excel at ping-pong, which should encourage researchers to look for a genetic explanation."

"Wade is long on speculating about what "is reasonable to assume", and short on circumspection of his own, or anthropologists', yarn-spinning. Most of the scenarios he reports have not been rigorously tested, nor is it clear how they could be. The book has many internal inconsistencies, and one can easily find contrary evidence or readily construct alternative 'just so' stories that invoke the same genetic scenario and the same kind of reasoning."

wow, in the world where oran kelley's opinions about evolution mattered, ouch.

p.s. anyone that questions lactase persistence, a canonical example of selection is being asinine and trying to pull a fast one, or didn't you notice?

Well, I realize my opinion on matters technical doesn't matter as much as someone who is actively researching in the field--like you?--but it would seem to me that you are focussing quite strongly on one statement here, when the point of the review is to criticize this person for making a whole cartload of claims that are rather more attention-grabbing than lactose tolerance.

Lactose tolerance is really a bit of a toss-off in the review, so let's grant you that one: you're right about lactose tolerance and they're wrong. But in the context of the review lactose tolerance is a nit.

My claim here is not to know the science better than you: it's that you look at least as disingenuous as your argumentative opponents. I may not be making my living in a laboratory, but you don't need lab goggles to see you have yet to present a single argument here that has any bearing on the point of the review. All you've done is cry "infidel."

I may not be making my living in a laboratory, but you don't need lab goggles to see you have yet to present a single argument here that has any bearing on the point of the review. All you've done is cry "infidel."

yes. i tend to do the same with creationists! i don't apologize for it, you know i'm an egoist. there are substantive critiques of much of the research that wade presents (which i tend to share to some extent). that book review does not go in that tack but attempts to obfuscate. and i just gave you the issue regard lactase, isn't that substance, or can't you recognize fact from fiction? again, you are under no obligation to read or credit my ex cathedra assertions. if i don't elaborate, it might be beause i have other obligations. in any case, i present the full text so you can make your own judgements (on the other weblog), you know my opinion.

and if you are curious, the entire first paragraph is misrepresentation (i read the book). but you can tell from the way it is couched that it is, so i see no reason why you should take their sage warnings to heart.

It is easy to claim that a trait is due to natural selection, but responsible selection-based arguments should have substantial experimental mechanistic support, at least for the fact of selection.

and oran, this here, this is no different than creationists and intelligent design types. rest assured, there will never be enough mechanistic support for some people, the goal posts will keep moving. there are cases where selection is the null hypothesis, plain and simple.

Linkage disqeuilibrium and allele statistics such as Tajima's D are in many cases a better way of determining selection than a mechanistic test: they don't require that you recreate past selective environments. Other approaches, such as a probability analysis of the way in which common mutations cluster in particular metabolic paths can also tell you a lot - you can apply this to many red-cell polymorphisms thought to have been selected as defenses against malaria Although nobody has yet, except for my first-cut analysis. Ken Weiss may not not be sure that alpha-thalassemia is a defense against malaria, but I am. Evidently he'd rather not know. Go figure.

The review disagrees exception to a lot of things that are simple facts. For example it takes exception to Wade's statement that "the alleles involved in differentiating the human population are likely to be of
the selected kind not the neutral kind. "
That statement happens to be true. As we check them out, the alleles differentiating races and ethnic groups _do_ mostly appear to be the products of recent selection. That is the case: check out the recent literature. Recent because they postdate the separation of the racial groups (and are therefore not universal), selected because what else coud have raised them to high frequency so fast?

gcochran:

One day I'll dig into the whole question of how a genetic change is deemed to be "likely" caused by selection, but I'm far from well-informed at the moment.

So I'll just have to take your word for the current state of the science, and thank you for the info to follow up on.

Anyhow, "Other best-case scenarios for human genetic adaptation, such as adult lactase persistence and skin colour, are also incomplete." Doesn't mean the authors don't believe the hypothesis, it means the evidence is not yet terribly strong in their view.

And that's beside the point anyhow. If Wade's book had been primarily about hereditary blood diseases that, everyone acknowledges, are "probably coevolving with the strong selective force of malaria," we wouldn't be having this conversation.

This, it seems to me, is the point of the review: "Explaining selection is particularly problematic for behavioural traits because of the powerful role of culture and facultative ability, which is probably what human evolution really favoured. Human phenotypic changes can far outpace genetic ones, making it challenging to know whether such traits are even genetic, much less what they 'evolved for' millennia ago."

The rest, while it may reflect a standard of evidence you regard as needlessly or mulishly rigorous, is just rhetorical lead-in. Perhaps TOO rhetorical? Fine. But still, ancillary.

And one has to suspect there's a lot of rhetorical motive behind dragging one's attention to these ancillary points.

To you parting question: I'd be specualting wildly, but . . . how about a relatively small pioneering population, combined with gentically-based but non-selective mating preferences encouraging certain phenotypic traits.

I guess the question would really have to be is natural selection really the only explanation for the circumsatnces you lay out. Is there a strong scientific consensus that what we might identify as common racial phenotypes reflect environmentally induced selection?

I've never regarded this as a particularly compelling question, but I'd even be willing to grant that natural selection is probably the answer.

But to say that "stressing genetic racial differences as he does is 'objective' and scientific, but stressing human similarities is 'political'" [not a direct quote from Wade, please note], that goes quite a bit further. Does the science unequivocally support the purported significance of probably-selected-for racial traits?

But to say that "stressing genetic racial differences as he does is 'objective' and scientific, but stressing human similarities is 'political'" [not a direct quote from Wade, please note], that goes quite a bit further. Does the science unequivocally support the purported significance of probably-selected-for racial traits?

yes, that's the point. the review puts paraphrases into his mouth. writing 500 word reviews isn't easy, and sometimes you do have to elide over complexities, but still, what they did is not acceptable. wade simply does not say what they say he says.