Saturday, June 27, 2009

The Great, Profound, and Valuable Works of Evolutionary Psychology

A few weeks ago I was having an email discussion about evolutionary psychology with Gad Saad. Readers may recall an earlier posting about Gad's work on the correlation between the length of one's fingers and the kinds of things one likes to buy in a store [Psychology and Finger Length].

One of my criticisms of evolutionary psychology is that its proponents don't usually seem to have a good handle on modern evolutionary biology. Gad argues that, while this may be true for some evolutionary psychologists, it's not a widespread problem. He, for example, considers himself to be very knowledgeable about evolution. His undergraduate degree is in Mathematics and Computer Science. He then went on to obtain an MBA, an MS in Management, and finally a PhD in Marketing [Gad Saad].

He is currently an Associate Professor in the Marketing Department at Concordia University, Montreal, Canada. But over the years he has learned a great deal about evolution and in 2008 he was appointed to the "Concordia University Research Chair in Evolutionary Behavioral Sciences and Darwinian Consumption." Gad explained to me that this appointment was recommended by several experienced evolutionary biologists.

We weren't making much progress in our email discussions. It seemed that we had been reading different accounts of evolutionary theory because we couldn't agree on some basic concepts. Nevertheless, Gad advanced a number of vigorous defenses of evolutionary psychology including the following point that I reproduce from our email exchange with his permission. (Actually, he gave me permission to post his list of "great, profound, and valuable works" but not the actual paragraph where he made the claim. I posted the actual claim because it differs from what Gad said in the comment to my earlier posting.)
You are indeed correct that evolutionary psychology has at times succumbed to the allure of just-so storytelling. That said, it is unfair (and frankly dishonest of you) to place all evolutionary behavioral scientists under the negative umbrella that you repeatedly do. Evolutionary psychologists produce great, profound, and valuable works, and at times can produce weaker works with tenuous conclusions. This holds true of biochemists as well. Physicists disagree as to whether String Theory is valid or not. Should we equally view physicists as providers of shoddy and controversial work?
I was intrigued by the claim that evolutionary psychologists have produced "great, profound, and valuable works" and I asked for examples. He supplied them but around that time I got distracted by real life and didn't follow up on our email exchanges.

Now Gad has posted his list in the comments to yesterday's posting on Why Evolutionary Psychology Is False.

I think it deserves wider coverage so here, without comment, is Gad Saad's list of the great, profound, and valuable works of evolutionary psychology. This is the best of the best by one of the leading experts in the field. I think we can get a good sense of the overall quality of the discipline by examining the list.
  1. Women alter their preferences for the facial features of men as a function of where they are in their menstrual cycles. When maximally fertile, they prefer men possessing markers of high testosterone.
  2. Babies display an immediate instinctual preference for symmetric faces (at an age that precedes the capacity for socialization).
  3. Children who suffer from congenital adrenal hyperplasia display a reversal in their toy preferences. Furthermore, using inter-species comparisons, vervet monkeys display the same sex-specific patterns of play/toy preferences as human infants. This suggests that contrary to the argument made by social constructivists, play has an evolved biological basis.
  4. Individuals who score high on an empathy scale are more likely to succumb to the contagion effects of yawning. This is indicative that this particular contagion might be linked to mimicry and/or Theory of Mind.
  5. How provocatively a woman dresses is highly correlated to her menstrual cycle (a form of sexual signaling found across countless Mammalian species).
  6. Culinary traditions are adaptations to local niches. For example, the extent to which a culture utilizes meat versus vegetables, spices, or salt is a cultural adaptation (this is what behavioral ecologists study).
  7. Maternal grandmothers and paternal grandfathers invest the most and the least respectively in their grandchildren. Whereas all four grandparents have a genetic relatedness coefficient of 0.25 with their grandchildren, they do not all carry the same level of "parental uncertainty." In the case of maternal grandmothers, there is no uncertainty whereas in the case of the paternal grandfather, there are two sources of uncertainty. This last fact drives the differential pattern of investment in the grandchildren.
  8. Good male dancers are symmetric (paper published in Nature). One would expect that some behavioral traits might correlate with phenotypic quality as honest signals of an individual's desirability on the mating market.
  9. Self-preference for perfumes is linked to one's immunogenetic profile (Major Histocompatibility Complex).
  10. When a baby is born, most family members (especially those of the mother) are likely to state that the baby looks like the father. This phenomenon is found in countless cultures despite the fact that it is objectively impossible to make such a claim of resemblance. The reason for this universally found cultural tradition lies in the need to assuage the fears of paternity uncertainty.
  11. Environmental stressors (e.g., father absence) and the onset of menarche (first menses) have been shown to be highly linked. In numerous species, the likelihood of a female becoming reproductively viable is affected by environmental contingencies.
  12. Women are less receptive to mandatory hospital DNA paternity testing (for obvious reasons). In other words, their willingness to adopt a new product/service is fully driven by an evolutionary-based calculus.
  13. Women can smell the most symmetric men. In other words, women have the capacity to identify men who possess the best phenotypic quality simply via their nose. This is what I have referred to as sensorial convergence.
  14. Using fMRI, the exposure to ecologically-relevant stimuli (e.g., beautiful faces) yields distinct neural activation patterns in men and women.
  15. In choosing a mate, humans tend to prefer the smell of others that are maximally dissimilar to them along the MHC. This ensures that offspring possess a greater "defensive coverage" in terms of their immunological system.


82 comments:

  1. "Women can smell the most symmetric men"

    Sounds about as convincing as finger length

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  2. honestly? I think there is something seriously fucked up with the statistics here.


    Do evo psych's ever stop to think about the fantastic mechanims they are assuming on the basis of flimsy correlations?

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  3. I would hope that social constructivists and evolutionary psychologists aren't, like, arch enemies or something!

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  4. I think that this comment might be my last one on this blog as it does not seem as though we are able to engage in an honest and fruitful debate. For example, I would have loved to know specific criticisms that might be levied against the 15 findings that I enunciated. Have any of the readers that have posted disparaging words about the findings read any of the articles in question?

    By the way, I did not proclaim that these were "the best of the best" as Larry suggested. I simply sought to include a heterogeneous set of findings that struck me as valuable and interesting.

    On a different note, I had thought of including some of Larry's comments from our private emails in my earlier post. Then I thought that this would be unethical as I had not obtained his permission (and hence I refrained from doing so).

    Larry on the other hand took a passage from an email that I had sent him and included it in his post, and lied about having gotten my permission to do so. Larry: Can you provide a copy of the email wherein you sought my permission and I granted it? I do not recall having had such a communique with you (I still have our email exchanges stored in my email account).

    I will bow out of this blog with the following words: I think that it is best to contribute to science in an honest and productive way rather than to constantly castigate the works of others. I have found that the great majority of readers of this blog are of the same mind set: "Evolutionary psychology and its practitioners are all idiotic fools and no evidence is going to ever sway our formed opinions." I gave it a shot but I have apparently failed at shifting any of the formed anti-EP opinions. Fair enough. Ciao amigos. Be well.

    Regards,

    Gad Saad

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  5. Larry said:

    "I think we can get a good sense of the overall quality of the discipline by examining the list."

    I think we can also say that Larry's lack of curiosity about the specifics of research in a field other than his own gives us a good sense of his intellectual depth. Hope you and this "A. Vargas" guy are very happy together...

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  6. You guys are calling foul and backing away? ALREADY? It must be a modus operandi.

    I made a completely sincere argument. If you're telling me women can smell symmetry on a man (I'm guessing, on the basis of a statistical correlation), this means either:

    1) there is a copleteley unknown fantastic mechanism by which symmetry is signaled through odoriferous molecules

    or

    2) there is something fucked up about the stadistics

    Same thing about finger ratios. If you have statitic evidenc ethat some ratio of your choice corelates with your propesnity to buy a certain product, then its either

    1) An unknown common mechanism relates these two traits (what on earth? beats me)

    or

    2) fucked up statistics.

    In many cases, these evo-spych studies fail to replicate. What do you think that tells you about the supposedly "significant" correlations they find?

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  7. Dr. Vargas,

    You seem pretty curious and reasonable. May I recommend that you read a book by John Manning entitled "Digit Ratio"?

    http://www.amazon.com/Digit-Ratio-Fertility-Behavior-Evolution/dp/081353030X/ref=sr_1_1?ie=UTF8&s=books&qid=1246141910&sr=8-1

    It gives the details of the rationale for the research into digit ratios.

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  8. As I’ve said before – in the end you will have to come to terms with evolutionary psychology, because you have no option. Either the human brain and mind are products of evolution; or they are not. It really is as simple as that. Oh, my mistake, you do have an option – you could concede to Denyse O’Leary.

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  9. Ford Prefect, ChiropractorSaturday, June 27, 2009 10:22:00 PM

    Anonymous—

    Is anyone denying that the human brain is an evolved product?

    Way to take the debate up a notch.

    The problem is adaptationism.

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  10. This comment has been removed by the author.

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  11. Is anyone denying that the human brain is an evolved product?

    Good point.

    Dismissing the whole concept of evolutionary psychology as opposed to the way it is practiced by most today is equivalent to denying that that behavior is influenced by genetics, a fact that is readily observed in humans and other animals. As our genomes are ultimately the product of evolution, (and I want to heavily emphasize that probably most of the forces shaping them are non-adaptive) behavior is a subject of study from an evolutionary perspective.

    I guess the problems stem from psychologists studying evolution rather than with evoliutonists (at least the ones who know their genetics) studying psychology

    P.S. Without being an expert I can list quite a few much more profound insights into human nature that have come out of evolutionary psychology that were not on that list

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  12. I agree with anonymous. Really, what other alternatives are there? There is no cohesive foundation of psychology that equates to evolution as a cohesive foundation of biology. I'm not saying there aren't some lousy theories in evo psych, but the same is true of every branch of science.

    I don't think all of human behavior is strictly adaptationist. I do, however, think that logic implies that a pretty good chunk of it is. I don't think all physiological characteristics are adaptationist also, but to think of the majority of them as spandrels is ridiculous.

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  13. A bit off topic: Larry, did you have permission to reprint Gad's email? I would assume so, but he claims otherwise.

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  14. Larry and Gad, this is interesting stuff about an important topic. Stop the personal sniping, and keep the discussions going.

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  15. Gad says,

    I think that this comment might be my last one on this blog as it does not seem as though we are able to engage in an honest and fruitful debate. For example, I would have loved to know specific criticisms that might be levied against the 15 findings that I enunciated.

    I can't speak for the others but I don't have time right now to investigate every one of the claims. That's why I didn't post them. When you posted them in the comments I thought they were interesting enough to make into a separate posting and generate discussion.

    By the way, I did not proclaim that these were "the best of the best" as Larry suggested. I simply sought to include a heterogeneous set of findings that struck me as valuable and interesting.

    That's correct. You did not claim they were the best of the best. That's an assumption I made. Am I correct in assuming that you have left some of the best examples of evolutionary psychology off your list? Can you mention a few?

    On a different note, I had thought of including some of Larry's comments from our private emails in my earlier post. Then I thought that this would be unethical as I had not obtained his permission (and hence I refrained from doing so).

    I asked for permission to post your list when I said, "If you were to mention just three or four "great, profound, and valuable works," I could post them on my blog and we could have a serious discussion about them." You subsequently agreed and sent the list. (June 10, 2009)

    Larry on the other hand took a passage from an email that I had sent him and included it in his post, and lied about having gotten my permission to do so. Larry: Can you provide a copy of the email wherein you sought my permission and I granted it? I do not recall having had such a communique with you (I still have our email exchanges stored in my email account).

    I did not get permission to post that passage from our email conversation and I have corrected the statement on my blog that says otherwise. I apologize for making a statement that was not true.

    However, when you posted your list in the comments to a previous posting you described our email conversation by saying ....

    Several weeks ago, Dr. Moran asked me via email to provide him a single valuable or interesting finding that has been generated via the evolutionary psychology field. At first, I refused to do so, as I told Larry that it was frankly outrageous to posit that of the countless articles that have been produced via this framework, not a single one could pass his "lofty" threshold. Larry retorted that my refusal to provide him with a single example should be taken as a confirmation of his low opinion of the EP field.

    That was a misrepresentation of my position and a misrepresentation of what you promised when you said that the field had produced "great, profound, and valuable works." There's a big difference between an "interesting finding" and "a great, profound, and valuable" work.

    After thinking about it carefully, I decided to post your exact words in order to refute your false accusations concerning our email conversation. I erred in stating that I had your permission to post your exact claim along with the list and I apologize for that. I should have just posted it without claiming to have your permission.

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  16. Gad Saad says,

    I will bow out of this blog with the following words: I think that it is best to contribute to science in an honest and productive way rather than to constantly castigate the works of others.

    I'm sorry you feel that way but it's how science works. Scientists are in the skepticism business. Criticizing the results of our colleagues is how we operate and it's how science progresses. Maybe criticism is an evolutionary adaptation and we just can't help it? :-)

    The fact that works of evolutionary psychology come under a lot of criticism should be of concern to us all. Either it means that the field is doing suspect science or it is on the verge of overthrowing major paradigms. Either way, criticism is healthy and desirable, right?

    If you are an evolutionary psychologist the worst thing you can do is whine about the criticism and refuse to speak out in public against the obvious abuses in the discipline.

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  17. Larry:

    Your reply to Gad Saad shows some pretty fancy footwork. However, it is an honest answer to Matt's question: mea culpa: I lied.

    Re: your comment under "Psychology and Finger Length" Monday, June 08, 2009 1:13 PM "And thanks for the advance apology concerning your ad hominem attack."

    Please see "Fallacies on fallacies" evolvingthoughts.net "ad hominem (the use of insult) is not a fallacy unless it is designed to mislead the listener. There is nothing wrong with calling someone who is a thief a thief."

    However, your comment "I suppose that in the mind of an evolutionary psychologist that counts as a valid excuse," is more easily interpreted as ad hominem attack.

    I will not say as Gad has "this comment might be my last one on this blog." However, this post has forced me to re-examine my bias against evolutionary psychology; I will take the time to examine a good portion of the claims on Gad Saad's list.

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  18. Bayesian Bouffant, FCDSunday, June 28, 2009 11:01:00 AM

    Matt: I'm not saying there aren't some lousy theories in evo psych, but the same is true of every branch of science.

    OK, so you agree that there are some lousy theories. What are the good ones? That is the question which remains unanswered.

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  19. I'm sorry you feel that way but it's how science works. Scientists are in the skepticism business. Criticizing the results of our colleagues is how we operate and it's how science progresses.

    If the criticism was mostly directed at the strengths and weakness of the study in question, then what you said is both true and fair. Unfortunately, you in particular invariably leaven your criticisms of the science with heaping doses of ridicule and scorn directed at the scientists. Further, you invariably use the weaknesses (as you judge) of the particular study in question as an indictment of the whole field.

    The fact that works of evolutionary psychology come under a lot of criticism should be of concern to us all. Either it means that the field is doing suspect science or it is on the verge of overthrowing major paradigms.

    This is a false dichotomy. People are intensely curious about what makes us tick, and so unlike most areas of scientific inquiry the general media is going to exploit that interest for their own commercial interests. (You can subscribe to magazines with titles like “Popular Psychology” and “Psychology Today”, but you won’t find equivalent general audience periodicals on topics like “Popular Development” or “Hox Genes Today”.) Unfortunately the general media is ill equipped to evaluate the soundness of the study (but quick to spot the potential for an interesting story). If the Biochemical Society Meetings were scrutinized and covered by the general media was closely as the psychology meetings, there would be a lot more criticism at biochemistry research. And you know this: 50% of the work in all abstracts will never see the light of day in a peer-reviewed paper because it’s crap, and the vast majority of the rest will fall far short of the “great, profound, valuable” standard you want to hold evo-psych to.

    Either way, criticism is healthy and desirable, right? If you are an evolutionary psychologist the worst thing you can do is whine about the criticism …

    No one has an obligation to remain engaged in a discussion with you when you have demonstrated that participation will continue to subject them to personal ridicule and scorn, particularly when you will use unfair tactics to do so. This post is a perfect example. While indeed you did ask for an example of "a great, profound, and valuable work", by the time you posted his responses, you knew (from his posting in the other thread) that he was categorizing the list he provided as “valuable or interesting finding”. Yet you prefaced the list with the following: "Gad Saad's list of the great, profound, and valuable works of evolutionary psychology."

    IMO that was flat out dishonorable of you.

    You drove away someone who was making an honest attempt to give the perspective of someone who actively works in the field, and who can blame him for leaving? Unfortunately, the Sandwalk blog is poorer as a result.

    BTW, what are these important “obvious abuses in the discipline” that you feel psychologist have a duty to speak out against? Exactly who is being abused, and exactly what is the harm being caused?

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  20. The MHC stuff is bullshit, just so you all know.

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  21. "OK, so you agree that there are some lousy theories. What are the good ones? That is the question which remains unanswered."

    Not to answer for people, but to answer in general...

    For one, the emerging cognitive scientific theory of religion is informed by evo psych. See the work of Boyer, Atran, Barrett, et al. I don't buy into all the adaptationist bullshit either. But you can't deny the good contributions. Ignorance of them is not evidence of their absence.

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  22. "The MHC stuff is bullshit, just so you all know."

    ERV
    Please clarify what MHC stands for in the context of your sentence.

    A quick check on Google idicates that MHC is the abbreviation for Medicine Hat College.

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  23. You would think that social constructivists and evolutionary psychologists would, like, you know, cooperate with each other? They don't seem to like each other very much!

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  24. Veronica: my guess is that the "MHC" to which ERV refers is the Major Histocompatibility Complex - see http://en.wikipedia.org/wiki/Major_histocompatibility_complex

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  25. Digit ratio work is just complete and utter nonsense, no merit, no science, just a perfect example of how to make a living out of talking shite.

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  26. Is it just me or did most of that list seem like utter bull.

    "12. Women are less receptive to mandatory hospital DNA paternity testing (for obvious reasons). In other words, their willingness to adopt a new product/service is fully driven by an evolutionary-based calculus."

    That last sentence sounds like one hell of a jump in logic, and it's not alone in that list. Maybe there's some data out there, but I'm too busy reading up on useful science to bother with looking it up. Either way, Larry's still correct in saying that nothing on Gad's list is anywhere close to a great, profound, and valuable work.

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  27. Ummm... "How provocatively a woman dresses is highly correlated to her menstrual cycle (a form of sexual signaling found across countless Mammalian species)."

    I have to be mis-reading this sentence. I'm quite sure not even chimps or bonobos dress more provocatively depending on their menstrual cycles ;-)

    (p.s... this is a different "Jim" than above)

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  28. Ford Prefect, Gym TeacherSunday, June 28, 2009 6:21:00 PM

    "I don't think all of human behavior is strictly adaptationist. I do, however, think that logic implies that a pretty good chunk of it is. I don't think all physiological characteristics are adaptationist also, but to think of the majority of them as spandrels is ridiculous."

    Why? Large brains for whatever reason must yield most of our intelligent capabilities for free. I think the human brain may be the single best example of spandrels in the biological world, but discerning this may be a long, arduous process.

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  29. Divalent says,

    This post is a perfect example. While indeed you did ask for an example of "a great, profound, and valuable work", by the time you posted his responses, you knew (from his posting in the other thread) that he was categorizing the list he provided as “valuable or interesting finding”. Yet you prefaced the list with the following: "Gad Saad's list of the great, profound, and valuable works of evolutionary psychology."

    Gad Saad complained when I posted his actual words because he knows damn well that the list he gave me was in direct response to the following request ...

    P.S. Can you give me a few examples of the "great, profound, and valuable works" that have been done by evolutionary psychologists? I can't think of any.

    In his email message of June 10, 2009 the list directly follows his quotation of my question. There's no escaping the conclusion that he intended his list to be a list of great, profound, and valuable works of evolutionary psychology.

    At the end of the list he quoted from another email message of mine when I said, "If you were to mention just three or four 'great, profound, and valuable works,' I could post them on my blog and we could have a serious discussion about them."

    His response was, "See above and my book."

    Now that you know the truth, what are you going to say to Gad Saad? I'll be very interested to see how you respond.

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  30. T.A. Lewis says,

    I don't buy into all the adaptationist bullshit either. But you can't deny the good contributions. Ignorance of them is not evidence of their absence.

    I'm trying to find examples of good contributions by evolutionary psychologists.

    You could help by supplying a short list of what you think are the very best scientific studies done by evolutionary psychologists.

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  31. "Babies display an immediate instinctual preference for symmetric faces (at an age that precedes the capacity for socialization)."

    Presuming, for the fun of it, that this is solidly established, what does it actually imply? Any neural adaptation for distinguishing human faces from not-human-faces is likely to respond more strongly to the stimuli which embody the difference between face and not-face in exaggerated form. (Likewise for a network trained to distinguish, say, male from female.) That the preferred stimuli are associated with "fitness" on some other scale could well be dumb luck.

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  32. In a final, desperate attempt to inject a note of sanity to these proceedings (apparently, ol' Larry's idea of "scientific discourse") I urge all curious and rational participants to read Richard Dawkins' afterword to "The Handbook of Evolutionary Psychology" (2005).

    http://www.amazon.com/Handbook-Evolutionary-Psychology-David-Buss/dp/0471264032/ref=sr_1_1?ie=UTF8&s=books&qid=1246240385&sr=8-1

    There is a difference, after all, between criticism, informed criticism, and ranting based on 3rd and 4th hand exposure to uninformed science journalism.

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  33. Blake Stacey - This one's for you. Check out, especially, the 2nd to last paragraph...

    http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002106

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  34. Skeezix, whens the last time Dawkins made a fruitful contribution to the field of evo. biology?

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  35. Ford said:

    "Skeezix, whens the last time Dawkins made a fruitful contribution to the field of evo. biology?"

    Well...A lot more recently than Darwin, Mendel, Fisher, Haldane, Dobzhansky, Mayr, Maynard Smith, Hamilton, Williams, Trivers, Wilson....shall I continue?

    I'm assuming you ARE aware of his contributions? And, I'm assuming you've heard of scientists like John Krebs? Or, would you just prefer to ignore the entirety of evolutionary biology?

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  36. Skeeziks points us to a paper. From the PloS One paper Methodology/Principal Findings

    Here we show that measurements of symmetry and sexual dimorphism from faces are related in humans, both in Europeans and African hunter-gatherers, and in a non-human primate. Using human judges, symmetry measurements were also related to perceived sexual dimorphism. In all samples, symmetric males had more masculine facial proportions and symmetric females had more feminine facial proportions.
    Conclusions/Significance

    Our findings support the claim that sexual dimorphism and symmetry in faces are signals advertising quality by providing evidence that there must be a biological mechanism linking the two traits during development . (rest deleted)


    The problem many have with the evolutionary psychology field is the "there must be" statements. No, there does not have to be. This is the classic "just so" problem that Gould and Lewontin attacked head on. These could be spurious correlations. More times than not, the authors state a direct unproven "belief", without any real backing.

    http://ethomas.web.wesleyan.edu/wescourses/2004s/ees227/01/spandrels.html

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  37. Bayesian Bouffant, FCDMonday, June 29, 2009 8:52:00 AM

    "For one, the emerging cognitive scientific theory of religion is informed by evo psych."

    OK, religion is an excellent study subject for evo psych. How many dozen evolutionary theories are there for the rise and prevalence of religion? Which of those many theories is best, i.e. has the best explanatory power and predictive power based on currently available evidence?

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  38. Skeezix-- There is a difference, after all, between criticism, informed criticism, and ranting based on 3rd and 4th hand exposure to uninformed science journalism.
    Okay, so why is Gad Saad, an expert in evolutionary psychology, putting forth MHC studies as 'support' for evolutionary psych?

    Immunologists will tell you that human MHC 'smelling' is BS. The organ mice use for 'smelling' these signals is vestigial (or simply nonexistant) in humans. The hundreds of genes that code for the 'sensors' in mice are all pseudogenes in humans. According to evolutionary biologists, we started losing it about the time we got tri-color vision.

    So who, exactly, is the informed 'expert' in this discussion?

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  39. The Other Jim quotes a paper I recommended as saying:
    "Our findings support the claim that sexual dimorphism and symmetry in faces are signals advertising quality by providing evidence that there must be a biological mechanism linking the two traits during development . (rest deleted)"

    I agree that the "must be" portion of the authors statement is inappropriate and, if I was a peer reviewer for the journal (a task that I have partaken in on many occasions for several other journals) I would have the "must be a" replaced with "is." But, you are de-emphasizing the fact that the authors are simply saying that their paper provides EVIDENCE for their claim. They are not claiming that anything is true, just that there is evidence for their interpretation.

    I fail to see how this relates to "just-so" stories (a phrase that, in my experience, when it is used, it's a pretty good sign that all thinking has stopped).

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  40. ERV said..."So who, exactly, is the informed 'expert' in this discussion?"

    Well, frankly, not me. I never made a claim to be an expert in this area and, as I recall, neither did Gad. He simply referenced some research by individuals that did claim some expertise. Here's a few more...and, I do believe they might have some expertise in immunology:

    Ziegler, A., Kentenich, H. and Uchanska-Ziegler, B. (2005). Female choice and the MHC.
    Trends in Immunology, 26, 496-502

    Penn, D. J. and Potts, W. K. (1999). The evolution of mating preferences and major
    histocompatibility complex genes. American Naturalist, 153, 145-164

    Yamazaki, K. and Beauchamp, G. K. (2005). Chemosensory recognition of olfactory
    individuality. Chemical Senses, 30, i142-i143

    Rather than lazily labeling something "BS", might it not be better to level a decent argument against those in your own field that disagree with you (I'm assuming you consider yourself an "expert" in this field)?

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  41. Skeezo, my point was that Dawkins is writing afterwords to evo. psych. books when he isn't really doing any work at all in the field.

    Krebs, Tooby, Cosmides et al. are in reality a small group of workers doing research that is widely disowned by the evolutionary biological community and all this shall be recorded as an odd footnote in the history of science, rooted in an atomistic worldview that will soon yield to the more potent forces of organismic biology.

    Whatever makes you think that I ignore the entirety of evolutionary biology? You actually think that I include evo. psych. under that heading? I prefer rigor to fantasizing.

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  42. Dawkins is a fool that thinks we must focus all evolution on natural selection just to fight the creationists better...
    He has made no tru notable scientific contributions, and none at all since the 70's, but he's good at writing paperbacks.
    His "selfish gene" views on evolution is the kind of cartoonish hogwash evopsych just love, but it is no "official" evolutionary biology, as they seem to think (in their ignorance).

    Gould, on the contraray, has made imprtant contributions to science. He also has the due respect for the complexity of evolution that DOES characterizes most evolutionary biologists. Most evolutionary biologists I know see Dawkins as a charlatan.

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  43. "Dawkins is a fool that thinks we must focus all evolution on natural selection "

    That is as far as I needed to read on your comment. If you want to contribute something to the discussion don't use fallacious straw-men, as anyone who is informed will probably ignore most of what you write.

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  44. Skeezix-- Rather than lazily labeling something "BS", might it not be better to level a decent argument against those in your own field that disagree with you (I'm assuming you consider yourself an "expert" in this field)?
    I already did. Way to read, there, champ.

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  45. Skeezix,

    I'll be a little more clear. In the PLoS Paper, the headings in the materials and methods are;
    1) Photographs 2) Measurements
    3) Descriptives and distributions of scores 4)Fluctuating asymmetry and directional asymmetry 5)Sexual dimorphism in measures 6)Correlations between measures of masculinity and with symmetry 7)Making composite images 8)Rating the composite images

    Even with your suggested revision, how does any observation in the paper "provid[e] evidence that there [is] a biological mechanism linking the two traits during development"?

    I'll leave out the bragging about being asked to peer-review papers, and the insults.

    ReplyDelete
  46. ERV said: "Immunologists will tell you that human MHC 'smelling' is BS"

    I'm aware that the vomeronasal organ isn't "smelling' and there exists some debate among scientists as to its functionality in different species. I referenced three articles by people claiming to have some expertise in this area. I asked you:

    "Rather than lazily labeling something "BS", might it not be better to level a decent argument against those in your own field that disagree with you (I'm assuming you consider yourself an "expert" in this field)?"

    The point of this question was to determine if you had, at some point in your long, illustrious career as a graduate student, ever heard of individuals doing research like this since, as you indicated, "Immunologists will tell you that human MHC smelling is BS" and to suggest that you might consider taking the debate up with those experts that don't agree with you.

    Here's another researcher you might want to brush up on:

    http://www.ncbi.nlm.nih.gov/pubmed/14624846

    Good luck with that dissertation defense there, champ...

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  47. Skeenix, I dont have to do anything.

    The field is appropriately isolating individuals still pursuing MHC magic (recent example). Much like evolutionary psychology, apparently, human MHC-VNO researchers make shit up without data to support said shit.

    Scientists dont take kindly to that nonsense.

    Unfortunately media outlets and, evidently, evolutionary psychologists, are more than happy to give these individuals attention.

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  48. ERV said:

    "human MHC-VNO researchers make shit up without data to support said shit."

    So...scientists that don't agree with you and your take on things (such as the examples I referenced) "make shit up" and are just full of "BS"? I have absolutely no problem with any outcome that is favored by the preponderance of the evidence and there is certainly a lot of disagreement on this issue (although not, I'm sure, in the eyes of the main protagonists on each side). But "making shit up"? Really? Any evidence for this?

    As for evolutionary psychology, I am an expert in that particular field and if you would care to read some of the seminal theoretical and empirical work, I'd be happy to discuss it with you. But, if you are convinced that scientists like myself just "make things up", well, that could be a tad problematic.

    ReplyDelete
  49. Dawkins comment on this blog:

    "To refute creationists, we have to explain the evolution of adaptation, and that means we have to concentrate on natural selection as the important driving force of evolution"

    ReplyDelete
  50. If you read the link I just posted, you would notice that it is not my personal opinion that VNO research is bullshit, or that the researchers who champion this research make shit up.

    A recent paper proposes the hypothesis that the human vomeronasal organ (VNO) provides crucial inhibitory chemosensory information that discourages mating between "inappropriate" partners (Foltan and Sedy 2009). New information about human chemical communication would be exciting; unfortunately, the authors provide no data to support their hypothesis aside from an anecdotal personal observation. The authors also poorly cite research articles. For example, the section titled "How the VNO influences human behavior" presents only rodent data without any accompanying comparisons to human behavior. The authors discuss the crucial role that an ion channel, canonical transient receptor potential 2 (TRPC2), plays in rodent VNO function without mentioning that the human trpc2 is a nonprotein-producing pseudogene (Wes et al. 1995; Liman and Innan 2003).

    ...

    In our view, the hypothesis proposed by Foltan and Sedy (2009) that the human VNO provides crucial inhibitory chemosensory information preventing inappropriate mating is unsound. They provide no data to support their claim, and the cited research literature is mischaracterized. They acknowledge that it is generally agreed that the human VNO is nonfunctional but contend it is crucial for normal human social behavior. They assume that all putative pheromonal communication requires the VNO, where the research literature clearly demonstrates that suspected pheromones can activate both the main and accessory olfactory systems.

    THEY MAKE SHIT UP.

    Everyone in immunology knows this. At least the immunologists Im around.

    Why dont the evo psych people, if they are using it as support for their field? Fools making fools out of you.

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  51. ERV...

    This is well before your time but, the great film critic Pauline Kael was once noted to have remarked that she couldn't believe that Nixon beat McGovern in the 1972 presidential election because, as she stated at the time, "Everyone I know voted for McGovern." It's my impression that there are more than a few immunologists and other scientists that might take issue with the conclusions reached in the paper you cited (which I DID read, btw.). The fact that, as you say, all the immunologists "you're around" agree with you comes as no surprise. The following indicates that there is more disagreement than you suggest:

    http://chemse.oxfordjournals.org/cgi/content/full/26/4/433

    Even though it's a 2001 article, it still suggests a large degree of variation in opinion that's likely to still exist.

    Look, I have no dog in this fight. Whatever way this literature turns out will be knowledge gained as far as I'm concerned. Again, as for evolutionary psychology, it appears that the crux of the vituperative nature of the debate may be the difference between the methods and evidentiary nature of "whole-organism" biology and molecular biology/biochemistry (such as you, Larry, and A. Vargas).

    Just a more-or-less random case in point. I have here in front of me a book entitled "The Evolution of Parental Care" by Tim Clutton-Brock. It is considered a classic in the field of evolutionary biology and behavioral ecology. There is hardly ANY biochemistry in this book, yet, it has allowed evolutionary biologists to predict and understand a great deal about parental behavior in any number of species, including humans.

    My question for you is a very serious one: Is this type of stuff "BS" and "making things up"?

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  52. A. Vargas said...

    Dawkins comment on this blog:

    When and where did Dawkins make the comment you quoted.

    Did you intend to say

    Dawkins comment on [his] blog

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  53. This appears to be an important point relevant to this discussion:

    "There is evidence for chemosensory communication in humans, as in the synchronization of menstrual cycles among women who live together (Stern and McClintock 1998). There is also an intriguing influence of the Major Histocompatibility Complex (MHC) genes of both receiver and donor on the outcome of human-odor preference studies (Jacob et al 2002: see Vomeronasal Receptor Genes for another intriguing connection - between VNO and MHC). Whether these are "pheromone" communications by the more rigorous criteria remains to be demonstrated and there is no evidence to suggest that they are mediated by the VNO. Of course, the existence of a VNO-mediated response does not prove that a stimulus substance is a pheromone. Nor does the existence of pheromone communication imply vomeronasal mediation." From, Michael Meredith, FSU, http://www.neuro.fsu.edu/~mmered/vomer/extendedText.htm

    This whole thing started out, after all, with your original comment re: MHC..."The MHC stuff is bullshit, just so you all know."

    Meredith is the supervising professor of one of the co-authors of the paper you linked me to. This comment seems a tad more measured and cautious than you're characterization of this literature.

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  54. fwiw, "the MHC thing" deserves perhaps a bit more than out-of-hand dismissal. the research is far from conclusive, but there is suggestive evidence that in some human populations mate choice is influenced by MHC type:

    http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1000184

    (see also references within)

    for whatever reason, this really seems to get people riled up; possibly because there is no "smoking gun" piece of evidence either way.

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  55. THIS blog. here:

    http://sandwalk.blogspot.com/2009/02/dawkins-on-chance.html

    ReplyDelete
  56. Skeezix posted this quotation from someone who is supposed to be knowledgeable in the field of evolutionary psychology.

    "There is evidence for chemosensory communication in humans, as in the synchronization of menstrual cycles among women who live together (Stern and McClintock 1998)."

    Skeezix himself says that he is a expert in evolutionary psychology so I think we can assume that the quotation refers to the level of science that's typical in this field.

    Here's the problem. Evidence for the synchronization of menstrual cycles is very weak. The best we can say about it is that it is controversial. It's really strange to see evolutionary psychologists quoting the McClintock studies without at least adding a qualifier or two.

    Here's a New York Times article that exhibits the correct amount of skepticism. This is encouraging, although hardly typical.

    The article refers to a paper by Yang and Schank (2006)published in the journal Human Nature. The abstract makes interesting reading ...

    It is widely believed that women who live together or who are close friends synchronize their menstrual cycles. We reexamined this phenomenon in two ways. First, we collected data on menstrual cycles from 186 Chinese women living in dorms for over a year. We found that women living in groups did not synchronize their cycles. Second, we reviewed the first study reporting menstrual synchrony. We found that group synchrony in that study was at the level of chance. We then show that cycle variability produces convergences and subsequent divergences of cycle onsets and may explain perceptions of synchrony.

    Now, I don't claim that the Yang and Schank study is definitive but it's not the only one that questions McClintock's original data and her subsequent follow-up.

    You can read a pretty good short summary on the Wikipedia entry [McClintock Effect]. Not only does it mention the unreliability of the data but it also points out that synchronization doesn't make a lot of sense when the cycles of individual women vary by several days.

    This illustrates part of the problem with the field of evolutionary psychology. Its practitioners don't seem to be very good at questioning their assumptions and looking for alternative explanations. They seem to be a very gullible group.

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  57. Larry said:

    "Skeezix posted this quotation from someone who is supposed to be knowledgeable in the field of evolutionary psychology."

    AND

    "Skeezix himself says that he is a expert in evolutionary psychology so I think we can assume that the quotation refers to the level of science that's typical in this field."

    The material I quoted was from Dr. Michael Meredith, a neuroscientist at Florida State University and, as far as I can tell, NOT an evolutionary psychologist. On his website, his research interests are described as follows:

    "Function of special chemoreceptors, especially the vomeronasal and nervus terminalis systems. Neural coding and integration in sensory systems, especially chemoreception. Neural control of behavior (currently neural mechanisms in male reproductive behavior). Brain and neuron function." http://www.bio.fsu.edu/faculty-meredith.php

    My focus in quoting him was in reference to the MHC discussion. I made no claim re: the menstrual synchrony portion of the quote and, so as not to mislead the easily mislead Larry, should not have included it.

    However, I think Larry's commentary here is a valuable object lesson to those of you who frequent this blog. Ol' Larry appears to see those eeevil evolutionary psychologisssssts and adaptationisssssts wherever he looks. Even to the point where he sees them in the words of a respected neuroscientist (no real fan of the MHC research, btw) who is obviously not an evolutionary psychologist, as a simple glance at his website presence would tell those interested in finding out rather than those who just want to hurl invective.

    Larry says that evolutionary psychologists are not "...very good at questioning their assumptions and looking for alternative explanations." Larry, in his typical manner, couldn't even be bothered with checking out the details of this individual's work before launching his tirade. My man, maybe "questioning assumptions" and "looking for alternative explanations" has been missing from your scientific repertoire for so long that you simply assume that they don't exist anywhere. Your "all these people are this way" type of thinking is sloppy and clearly on display in this blog on a consistent basis. If you could stop throwing accusations around long enough to just listen and converse civilly, it might be a much more enlightening experience for your visitors.

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  58. Skeezix says,

    However, I think Larry's commentary here is a valuable object lesson to those of you who frequent this blog. Ol' Larry appears to see those eeevil evolutionary psychologisssssts and adaptationisssssts wherever he looks. Even to the point where he sees them in the words of a respected neuroscientist (no real fan of the MHC research, btw) who is obviously not an evolutionary psychologist, as a simple glance at his website presence would tell those interested in finding out rather than those who just want to hurl invective.

    Touché.

    In this case it's a "respected neuroscientist" who didn't make the effort to check his facts and it's an expert on evolutionary psychology who posted his comment as if it were support for the idea that evolutionary psychologists base their opinions on evidence and not speculation.

    You said that "Meredith is the supervising professor of one of the co-authors of the paper you linked me to." and I jumped to the wrong conclusion. I apologize.

    Skeezix says,

    Larry says that evolutionary psychologists are not "...very good at questioning their assumptions and looking for alternative explanations." Larry, in his typical manner, couldn't even be bothered with checking out the details of this individual's work before launching his tirade.

    I didn't post that quotation in support of my position. You did. I know enough about this literature to know that the claim of menstrual synchronization is suspect.

    Did you know that? 'Cause if you did it might have caused you to be skeptical about the other part of the quotation as well.

    With respect to the ability to detect HLA antigens, I think we can all agree that there's contradictory evidence and the jury is still out.

    So when Gad Saad includes the following in his list of contributions ...

    15. In choosing a mate, humans tend to prefer the smell of others that are maximally dissimilar to them along the MHC. This ensures that offspring possess a greater "defensive coverage" in terms of their immunological system.

    I think it's fair to say that he is somewhat exaggerating the firmness of that conclusion. Most of us would be a lot more skeptical and we would say things like, "There is some evidence to suggest that ..." or "While the evidence is contradictory, it is possible that ..."

    So, Skeezix, let's cut to the chase. Do you, or do you not, think Gad is right to claim that this is one of the valuable contributions of evolutionary psychology?

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  59. Larry,

    If you take a look at the thread re: MHC (mostly with "ERV"), you'll see that I never claimed to be an expert in this area and never claimed to "have a dog in this fight." I was simply taking issue with ERV's flippant dismissal of research in this area that came to different conclusions than she does. In fact, I agree with you. This research (as well as the synchrony research) is terribly muddled right now. This will change only by further research by people with open minds rather than dismissive "turf-wars." I AM skeptical about ANY firm conclusion in these areas and, again, was only providing the Meredith quote in an attempt to help ERV to understand that comments like "the MHC stuff is BS" were not terribly helpful.

    As regards your last couple of points, I agree that "the evidence favors" type of qualifiers are woefully missing from much scientific discussion. But, it's been my experience that scientists in ALL disciplines are equally guilty of this. I see no evidence that evolutionary psychologists are more guilty of this than any other group. However, if one looks for this problem selectively as it relates to only one discipline, they will likely find that that group is uniquely guilty of this oversight. I dare say that if one focused their concentration on biochemists, one would come away with similar conclusions. But...this is all just rank, dataless speculation (on both our parts) and I would prefer to not turn it into a pissing contest.

    With respect to your last query: I think Gad has the right to claim value for any research that he wants. This research has been published in mainline peer-reviewed journals and plays by the rules. The fact that it might seem less valuable, or even trivial, to scientists in other areas is irrelevant.

    As for me, I think there are seminal theoretical and empirical works that are not only central to evolutionary psychology, but evolutionary biology. Again, I urge you and other interested people, to read (or, at least, look at) the recent "Handbook of Evolutionary Psychology" (2005) to get some idea of what this theory/research looks like.

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  60. A limited preview of the Handbook of Evolutionary Psychology I referred to in the previous post is available from Google Books:

    http://books.google.com/books?id=esDW3xTKoLIC&printsec=frontcover&dq=handbook+of+evolutionary+psychology&ei=k29KSqLQD46-yQTz5IjPBg&client=firefox-a

    However, I assume the inevitable criticism will be based on a more thorough familiarity with the specific research reviewed rather than simply on the table of contents...

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  61. Skeezix, I read the first chapter ("Conceptual Foundations of Evolutionary Psychology") in the handbook. It confirms the general impression I have that evolutionary psychologists are committed to the adaptationist program (see page 10).

    It also confirms another general impression; namely that evolutionary psychologists don't share the same view of evolution that most evolutionary biologists support. That first chapter repeats claims that I've seen before in the evolutionary psychology literature. It divides evolutionary change into three parts: adaptations, by-products of adaptations, and noise (page 25). Dyslexia is an example of "noise."

    Most evolutionary biologists recognize that random genetic drift is an important mechanism of evolution. Some features of organisms are not adaptations and are not by-products of adaptations. They just arose and became fixed by accident. Most (but not all) evolutionary biologists think that fixation by random genetic drift should be the default hypothesis in studies of evolution.

    I get the feeling that evolutionary psychologists disagree. That's fine, they are entitled to be adaptationists if they like. We have those debates all the time in the field of evolutionary biology.

    What troubles me the most about evolutionary psychologists is that they don't even seem to recognize that there's another point of view out there. Maybe some behaviors have a genetic component but they are not adaptations. They may even me maladaptive.

    There an example in the book. Chapter 5 is all about "Controversial Issues in Evolutionary Psychology." It deals with lots of issues but the basic assumption of adaptationism isn't even questioned. The words "random genetic drift" don't even apper in the chapter as far as I can see. There's lots of praise for Dawkins and E.O. Wilson but the author doesn't seem to be aware of the fact that those men don't speak for all evolutionary biologists.

    Do you think this is a general problem in the field of evolutionary psychology or have I just been reading the wrong papers?

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  62. Larry,

    First of all, I appreciate you taking the time to review some of the material I referred you to and your thoughtful commentary.

    You said that you were troubled most by evolutionary psychologists' failure to recognize that there was another point of view with respect to the mechanism of genetic drift. All I can really tell you is that EP is informed by the same theoretical tradition as much of evolutionary biology; that of Fisher, Hamilton, Williams, Trivers, etc. The consensus in this tradition is that drift is not a powerful enough mechanism to "create" the degree of complex functional organization seen in "whole" organisms. The relative importance of various evolutionary mechanisms, of course, varies with such things as population size, etc. but, as I said, complex organismic design is assumed to require the more powerful mechanism of natural/sexual selection. That's the thinking, anyway. I believe you and Dawkins had a dust up on this issue a few months ago. It's probably one of those "agree to disagree" sort of things.

    Because of this tradition, drift and other mechanisms recede to the background, as they do in other work in (some) evolutionary biology. Earlier in a comment, I made reference to a classic work by Tim Clutton-Brock (The Evolution of Parental Care). This is pretty standard issue evolutionary biology (or, behavioral ecology, if you wish) and it is an example of work that has had an enormous impact in terms of the generation of falsifiable hypotheses in a wide variety of research areas. I'm pretty sure that drift wasn't mentioned there either.

    Evolutionary psychology is an initial attempt to apply this fruitful approach to an understanding of human behavior. As in every discipline, especially relatively young ones, the quality of research varies. However, the theoretical rationale and empirical realizations of a great deal of the work warrants serious consideration.

    I would genuinely like to hear your opinion re: the relationship between genetic drift and complex, functional, organismic design, particularly why, in your opinion, this mechanism would be expected to result in such design more efficiently than selection.

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  63. The role of drift in adaptive shifts of opsins in fish:

    Yokoyama S et al. (2008) Elucidation of phenotypic adaptations: Molecular analyses of dim-light vision proteins in vertebrates. Proc Natl Acad Sci USA 105:13480–13485.

    The huge amount of neutral genetic change is often portrayed by adaptationists as an irrelevant "background noise" with no phenotypic relevance.
    Alas, it STILL is structural change, and structure, believe it or not, has consequences.

    The example above (and many others) illustrate how changes with no phenotypic effect must first be accumulated by drift before certain phenotypic changes may occur.

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  64. A. Vargas said:

    "...changes with no phenotypic effect must first be accumulated by drift before certain phenotypic changes may occur."

    That's my understanding of how drift might work as one of the mechanisms of evolution. But, in order for any of these certain phenotypic changes to be maintained over time and, eventually, fixated in a population of whole organisms, isn't selection a more efficient force for that?

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  65. Please read the paper. You can only have an adaptive change in opsin structure if previous "silent" changes in the sequence have been accumulated by drift.

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  66. Skeezix says,

    All I can really tell you is that EP is informed by the same theoretical tradition as much of evolutionary biology; that of Fisher, Hamilton, Williams, Trivers, etc. The consensus in this tradition is that drift is not a powerful enough mechanism to "create" the degree of complex functional organization seen in "whole" organisms.

    That's a classic adaptationist statement.

    The problem with an adaptationist research program is not that natural selection can produce complex design. It's in assuming that everything is a complex design. You don't consider other mechanisms of evolution because you start with the ASSUMPTION that the thing you're examining is an adaptation. It's called begging the question.

    I'm well aware of the fact that EP is "informed" by the old traditional evolutionary biology of Fisher, Hamilton, and Williams. That's the problem.

    I get the impression that most of you don't even know that the old tradition has been challenged in the past forty years.

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  67. A. Vargas: Your point doesn't support Larry. Here is what Larry said:

    "Most evolutionary biologists recognize that random genetic drift is an important mechanism of evolution. Some features of organisms are not adaptations and are not by-products of adaptations. They just arose and became fixed by accident"

    But the opsin in deep sea fish match the light environment are adaptations, at least according to the paper you cited. That drift was a component of the evolution of the AA sequence is not relevant to Larry's argument, that complex phenotypes (not AA substitutions) might be present because of drift and *not adaptation* or by-product.

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  68. Please read the paper. It is an example of the role of drift in the origin of adaptation (not merely a component). No drift, no adaptation.

    Larry doesn't say this. As far as I know, Larry thinks drift does not have a role in the origin adaptation. He thinks adaptation is the turf of selection.

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  69. Larry: "Some features of organisms are not adaptations and are not by-products of adaptations. They just arose and became fixed by accident."

    This is truly an ironic statement when applied in the course of criticizing a related field for not producing the goods. Show me the voluminous data that establish that some non-trivial phenotypically-visible characteristic that has the potential to affect fitness in a real world organism nonetheless arose by drift. You CAN’T.

    And it’s not because such characteristics can’t arise by drift. It’s because proving it in any particular instance is extraordinarily difficult. You need access to the complete natural history of all the relevant alleles to show that there is not now, and never was in the past, a time when the environment would favor the trait. You can model the phenomenon of drift based on sound theoretical premises and show on a probabilistic basis that it must be important, but proving it in any given instance is the tough nut. Drift is a sound mechanism beyond merely neutral changes to the genome, but not because there are copious examples to support it.

    Evolutionary psychology is similarly premised on a strong theoretical framework: some behaviors clearly DO have a genetic component, DO have fitness consequences, and CAN be selected for. This is NOT controversial (except for those that don’t like the consequences for political reasons). Unlike more Mendelian traits, there is every reason to expect that behaviors are going to be extremely hard to pin down to a specific set of genes.

    For most traits where even the strongest skeptic would concede it’s a bona fide adaptation, the evidence remains circumstantial: it’s the most parsimonious explanation in the face of a plausible selective advantage and a reasonable mechanism. The drift hypothesis is mostly the one you are left with when the weight of the evidence rules out all the others. Essentially, it’s the null hypothesis. As a working strategy its not a very useful hypothesis to structure your investigations around because you end up having to rigorously test all the others anyway.

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  70. Vargas said:

    "Please read the paper."

    I did...

    Larry said:

    "I get the impression that most of you don't even know that the old tradition has been challenged in the past forty years."

    I am completely aware of the controversy in this area. Notably, of the contentions of Kimura and others in that tradition. While I am not a molecular biologist, I believe I have a handle on the outline of the debate. But why do you guys insist on making this an either/or question? It seems perfectly reasonable for molecular biologists to emphasize drift more than other evolutionary scientists just due to the nature of their subject matter. But, if someone is researching the patterns of sexual dimorphism, mate choice, and intersexual aggresion (for example) in penguins, peccaries, or people, selectionist thinking has proven over and over again to be more useful, parsimonious, and falsifiable.

    Speaking for myself and dozens of other evolutionary psychologists and biologists, I don't "assume that everything is complex design." But, at the "whole organism" level of analysis, this assumption has yielded spectacular results. I realize how you have dismissed people like Jerry Coyne in previous comments but, his treatment of drift in WEIT (for example) is a serious position, one that I share, and one that diminishes the work of those who hold it not one iota in terms of the types of research questions posed by these individuals.

    Again, I ask you: Why, in your opinion, would drift be expected to result in design at this level of analysis more efficiently than selection?

    You said that you are "aware of the fact that EP is "informed" by the old traditional evolutionary biology of Fisher, Hamilton, and Williams. That's the problem." No it's not. And scream and bellow as you might, this work will continue.

    (And, I am familiar with the logical fallacy known as "begging the question" so your condescension displayed by directing me to Wikipedia [the reference of champions!] is unnecessary).

    Again, your constant assumption that disagreement with you must obviously mean ignorance on the opposition's part has ended any interest I had (for a brief moment there when you actually seemed interested in respectful dialogue) in continuing this discussion. So, get your last "dig" in and then continue with your bullying tirades.

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  71. Vargas:

    I'm asking you how the paper you cited is relevant to Larry's claim that "Some features of organisms are not adaptations and are not by-products of adaptations. They just arose and became fixed by accident". That claim is the essence of this posting and thread, so if it is not relevant to the claim above, then I don't see how it is relevant to this thread. Again, the authors of the paper you cite claim the *functional* variation is adaptive and were not "fixed by accident"

    That said, the cited paper and the citrate paper by Lenski are sweet empirical examples of the role of chance events in adaptive evolution.

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  72. This comment has been removed by the author.

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  73. A final clarification: I agree with larry that lots of phenotypic traits are non-adaptive.
    But you DO catch him with his pants down on the topic of the evolution of adaptations, since he apparently doesn't know any other explanation for adaptation than natural selection.

    I am a bit more well-informed. Natural selection is simply an insufficient notion for understanding the evolution of adaptation. No matter what you may have happened to say to dumb ole creationists, ok?

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  74. A. Vargas said: "Natural selection is simply an insufficient notion for understanding the evolution of adaptation."

    Agreed For the naive, though, the conclusion seems wicked counter-intuitive. But they, and anybody who disagrees with the statement should be hit over the head with the fish opsin paper and/or Lenski's citrate metabolism paper (both in PNAS, interestingly, and not Science or Nature).

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  75. This comment has been removed by the author.

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  76. Now, mid prof, in the opsin study, we need fixation of "silent" mutations by drift for adaptation to eventually change.You MIGHT just be able to realize then, that organisms DO accumulate non-adaptive traits If you think non-adaptive traits do not exist, you cannot accept the opsin study, can't you.

    All of which is simply ridiculous. The existence of non-adaptive traits is a basic reality. Only panglossian crackpots can think everything may have a function.

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  77. middle.professor said...

    (both in PNAS, interestingly, and not Science or Nature).

    Not so surprising. Most of the excellent papers coming out of late are not in Science or Nature. In biology, S&N seem to like "exciting" much more than substance at the moment, IMHO.

    -Jim

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  78. Skeezix says.

    (And, I am familiar with the logical fallacy known as "begging the question" so your condescension displayed by directing me to Wikipedia [the reference of champions!] is unnecessary).

    It wasn't only you I was worried about. Most people misuse the term "begging the question." They think it means "provoking an obvious question." That's why I put in the link.

    Again, your constant assumption that disagreement with you must obviously mean ignorance on the opposition's part has ended any interest I had (for a brief moment there when you actually seemed interested in respectful dialogue) in continuing this discussion. So, get your last "dig" in and then continue with your bullying tirades.

    irony.

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  79. Divalent says,

    Evolutionary psychology is similarly premised on a strong theoretical framework: some behaviors clearly DO have a genetic component, DO have fitness consequences, and CAN be selected for.

    I agree that there are some clear examples of traits that fulfill these criteria.

    However, there are many that don't and the typical evolutionary psychologist simply ASSUMES that a trait is genetic, that is has significant fitness consequences, and that it was selected for in the past.

    Once you understand that the default evolutionary assumption is evolution by accident then you realize that you have to actually make a case for significant fitness benefits rather than just assuming them.

    Take the study I discussed earlier, Why Won't Your Daughter Call Home?, for example.

    What is the evidence for genes (alleles) that control incest avoidance? Why couldn't it just be cultural? Was there ever a time in human history when these alleles didn't exist and daughters mated freely with their close relatives?

    What is the actual fitness benefit of a gene (allele) that makes you avoid taking to your father when you are ovulating? Imagine that a mutation arose today in one or more of the incest avoidance genes so that the newborn was no longer genetically predisposed to avoid mating with close relatives. Would that person and their descendants be at a serious fitness disadvantage?

    I don't think so—and I don't think it would be any worse if everyone else carried the mutant allele. Almost all matings would still be outcrosses.

    The problem is not whether you can defend the adaptationist program by quoting statistics on inbreeding. The problem is that the debate never occurs in the evolutionary psychology literature. It's just ASSUMED that there have to be genes for incest avoidance and that the avoidance alleles confer significant fitness benefit.

    That's why the abstract concludes with, "Conclusion: this is the first evidence of adaptation in human females to avoid affiliation with male kin when fertility is at its highest."

    Divalent, do you agree with that conclusion? When did this adaptation occur? Was there a time when human populations didn't have this trait? Is this a good example of the "strong theoretical framework" upon which evolutionary psychology is based?

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  80. At any rate, I liked some of the vadlo evolution cartoons!

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  81. I could make this list much longer. But I would recommend people to read Buss book on evolution psychology. It's great and simple.

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