tag:blogger.com,1999:blog-37148773.post6291509639172706384..comments2024-03-27T14:50:47.345-04:00Comments on <center>Sandwalk</center>: The Central Failure of Evolutionary PsychologyLarry Moranhttp://www.blogger.com/profile/05756598746605455848noreply@blogger.comBlogger11125tag:blogger.com,1999:blog-37148773.post-84107407659963328952007-06-26T07:07:00.000-04:002007-06-26T07:07:00.000-04:00Erm, well EP never claims to explain cultural chan...Erm, well EP never claims to explain cultural change actually, so this post only hits a straw man.<BR/><BR/>EP does claim to explain the universal cognitive mechanisms which underlie human cultural capacities and behaviour, and hence which allow for (and constrain) cultural and behavioural variation.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-37148773.post-1212620287931064022007-03-16T15:29:00.000-04:002007-03-16T15:29:00.000-04:00Just to clarify:Before one proposes that a varying...Just to clarify:<BR/><BR/>Before one proposes that a varying trait is merely a phenotypic variation of a Darwinian adaptation, one should demonstrate a proof of mere phenotypic variation before a wholesale proposal that the trait is Darwinian. Some varying traits are variations of genetic imperatives and some are not, and particularly where behavior is ocncerned (not skin color), I suggest we be careful in just ignoring cultural and developmental determinants. If the focus is behavior as a Darwinian adaptation, we need extra care -- not less care.<BR/><BR/>Dan AginDan Aginhttps://www.blogger.com/profile/17180559839959161283noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-2640816145802956582007-02-20T10:50:00.000-05:002007-02-20T10:50:00.000-05:00Larry, there are a great many behaviors that are c...Larry, there are a great many behaviors that are common across much of humanity: a number of the core facial expressions, for example; the institution of marriage; incest taboos; a greater tolerance for male infidelity in marriage than for female infidelity, to name just a few. This poses the reverse challenge: if all behaviors are culturally defined, then why are <I>so many</I> behaviors common across so many different cultures?Chris Crawfordhttps://www.blogger.com/profile/14926445098765433310noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-3203281463596127872007-02-20T06:22:00.000-05:002007-02-20T06:22:00.000-05:00Greg Laden says,Larry ... sorry, I completely disa...Greg Laden says,<BR/><BR/><I>Larry ... sorry, I completely disagree with Agin's premise. Consider applying the rule that a "trait" to be considered an adaptation must be universal and very deep in time to all traits.</I><BR/><BR/>I agree that these are not absolute requirements. There are lots of genetic traits that are currently segregating in our population (i.e., not universal) and some that may have arisen within the past 100,000 years.<BR/><BR/>The point, in <B>my</B> opinion, is that in order to mount a convincing case for a genetic component you have to postulate a behavior that's nearly universal. I admit that you could try and demonstrate that the differences in behavior between, say, black Americans and those of European descent, might be due to genetic differences in the populations, but that's much harder to prove.<BR/><BR/>The point about a trait being ancient is just simple population genetics. It takes thousands of generations to fix an allele that only confers a small benefit. If the evolutionary psychologists postulate that this allele conferred an advantage to our hunter-gatherer ancestors then that's when it would have become fixed in the population. That means it arose much earlier.Larry Moranhttps://www.blogger.com/profile/05756598746605455848noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-5997289135221981132007-02-19T13:28:00.000-05:002007-02-19T13:28:00.000-05:00According to your logic, the existence of black-sk...According to your logic, the existence of black-skinned people is a cultural phenomenon, because black skin is not universal across geography.<BR/><BR/>C'mon, guys, you can do better than this.Chris Crawfordhttps://www.blogger.com/profile/14926445098765433310noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-48108598469970238532007-02-19T10:07:00.000-05:002007-02-19T10:07:00.000-05:00Yes, Agin's argument is sloppy, this part in parti...Yes, Agin's argument is sloppy, this part in particular:<BR/><BR/><I>Since Darwinian evolution can only work across enormous ("geological") time scales, which means nothing much has probably happened in the way of Darwinian human evolution during the past 100,000 years...</I><BR/><BR/>Has he not heard about the PLoS article "A Map of Recent Positive Selection in the Human Genome"? Or the loads of evidence from other species demonstrating rapid natural selection?<BR/><BR/>Steve LaBonne wrote: <I>But I can't believe that Larry's animus has led him to be impressed by a laughably bad argument that he would dismiss wth contempt in any other context. Especially when he himself offered some much more cogent objections in the "Another Boring Just-So Story" post.</I><BR/><BR/>Actually there is some serious research into the Westermarck hypothesis. See my answer to that post, or this paper (which has a good discussion of previous results that should be interesting to skeptics as well):<BR/><BR/>http://www.sscnet.ucla.edu/anthro/faculty/fessler/pubs/Fessler3rdPartyIncest.pdfAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-37148773.post-5272049595456479062007-02-19T08:51:00.000-05:002007-02-19T08:51:00.000-05:00Greg is correct. I share with Larry a general cont...Greg is correct. I share with Larry a general contempt for the rubbishy armchair theorizing that gets dressed up with the name "evolutionary psychology", and I even suspect that the whole project will never get off thte ground in a serious way (probably under a different name, to escape the taint) until a good deal more is known about the brain. But I can't believe that Larry's animus has led him to be impressed by a laughably bad argument that he would dismiss wth contempt in any other context. Especially when he himself offered some much more cogent objections in the "Another Boring Just-So Story" post.<BR/><BR/>I mean, forget behavior and take the hoariest, most trivial of Gentics 101 textbook examples. A genotype that predisposes its bearers to above-average stature won't be expressed in a population suffering from widespread malnutrition. Therefore it's not "universal". So what?Steve LaBonnehttps://www.blogger.com/profile/05315820864846104986noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-10709057546449754452007-02-19T08:26:00.000-05:002007-02-19T08:26:00.000-05:00Larry ... sorry, I completely disagree with Agin's...Larry ... sorry, I completely disagree with Agin's premise. Consider applying the rule that a "trait" to be considered an adaptation must be universal and very deep in time to all traits. This allows for zero populational variation, zero local adaptation, zero learning as an adaptive process, etc. For instance what a predator hunts and how it does is is probably adaptive and under selection. But some vertebrate predators vary across populations because of a combination of learned behavior, local conditions, and even some physical trait variation that is interpopulational. By this logic, hunting behavior by a predator is not "darwinian" (i.e. not shaped by natural selection). This is a bunch of hooey.<BR/><BR/>This is not the central failure of evolutionary psychology, not even close. <BR/><BR/>There are other factors that play that role.Greg Ladenhttps://www.blogger.com/profile/03973115018538144984noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-67364834267880180612007-02-19T01:41:00.000-05:002007-02-19T01:41:00.000-05:00I said, "humans having two arms and two legs is a ...I said, "humans having two arms and two legs is a universal, hereditary trait" -- I meant to add that a human with <B>one</B> leg does not necessarily require an evolutionary explanation. Ditto for a fair number of human behaviors and most specific actions. We have psychology, sociology, etc. to explain those.Nick (Matzke)https://www.blogger.com/profile/17024530213011582673noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-21181044561589194682007-02-19T01:39:00.000-05:002007-02-19T01:39:00.000-05:00This is very true, [* and **] and I can't understa...This is very true, [* and **] and I can't understand why it is not more widely understood -- although I suspect all of the more serious people, like Melvin Konner, understand it.<BR/><BR/>I like to use an analogy: humans having two arms and two legs is a universal, hereditary trait. This is the sort of thing that is useful to explain with the various evolutionary causes (ancestry, selection, exaptation, etc.).<BR/><BR/>* It should also be stated that one should have strong evidence that a trait is actually genetic before hypothesizing about an adaptationist explanation. Homosexuality is a case where this is often assumed but AFAIK with squat for evidence.<BR/><BR/>** There are some careful exceptions to the cultural universality rule. E.g.: (1) diabetes seems to be a case where innate constitution interacts with modern diets to produce the condition in certain populations. (2) Adult lactose tolerance is only found in certain cultures, as a result of adaptation to cattle/goat-herding and the resulting availability of milk for adults. This is a genetic trait that has not spread to fixation. I guess these are not exactly strictly behavioral traits but it gives an idea of where exceptions might be.Nick (Matzke)https://www.blogger.com/profile/17024530213011582673noreply@blogger.comtag:blogger.com,1999:blog-37148773.post-22561270074254142532007-02-19T00:38:00.000-05:002007-02-19T00:38:00.000-05:00amen! to that ... sometimes Dawkin's efforts seem ...amen! to that ... sometimes Dawkin's efforts seem a bit unconvincing to me. Though in general I agree that a larger survival feature must have evolved by a careful selection process. <BR/><BR/>But should every random auxiliary feature that seems less to do with survival have to be explained by evolution? for e.g. human eye brows? Can't humans have dog ears?<BR/><BR/>It is safe to say "we don't know" when we don't.bharathhttps://www.blogger.com/profile/17373725719154449138noreply@blogger.com