From Biology News Net comes this crazy article [Why aren't humans furry? Stone-Age moms could be the answer.
Medical Hypotheses, an Elsevier publication, has announced the winner of the 2006 David Horrobin Prize for medical theory. Written by Judith Rich-Harris, author of The Nurture Assumption and No Two Alike, the article, "Parental selection: a third selection process in the evolution of human hairlessness and skin color" was judged to best embody the spirit of the journal. The £1,000 prize, launched in 2004, is awarded annually and named in honour of Dr. David Horrobin, the renowned researcher, biotechnology expert and founder of Medical Hypotheses who died in 2003.This can't be correct, can it? An apparently respectable organization giving a prize to someone who postulates that stone-age women killed off their hairy children and kept the hairless ones and that's why we don't have hair? It's a joke, right?
Harris' paper describes Stone Age societies in which the mother of a newborn had to decide whether she had the resources to nurture her baby. The newborn's appearance probably influenced whether the mother kept or abandoned it. An attractive baby was more likely to be kept and reared.
Harris' theory is that this kind of parental selection may have been an important force in evolution. If Stone Age people believed that hairless babies were more attractive than hairy ones, this could explain why humans are the only apes lacking a coat of fur. Harris suggests that Neanderthals must have been furry in order to survive the Ice Age. Our species would have seen them as "animals" and potential prey. Harris’ hypothesis continues that Neanderthals went extinct because human ancestors ate them.
This year's prize judge was Professor Jonathan Rees FMedSci of Edinburgh University, Scotland – co-discoverer of the 'red hair gene'. Professor Rees said: "This paper is an excellent example of the kind of bold thinking and theorizing which David Horrobin intended to encourage when he began Medical Hypotheses. I hope that Judith Rich Harris' idea provokes debate and further investigation of this topic."
"Bold thinking" indeed. I can think of better words to describe that "theory."
This has to be a joke. It somehow HAS to be.
ReplyDeleteHas anyone heard of this journal before? From their web site I see this er interesting statement:
ReplyDelete“Medical Hypotheses takes a deliberately different approach to peer review. Most contemporary practice tends to discriminate against radical ideas that conflict with current theory and practice. Medical Hypotheses will publish radical ideas, so long as they are coherent and clearly expressed. Furthermore, traditional peer review can oblige authors to distort their true views to satisfy referees, and so diminish authorial responsibility and accountability. In Medical Hypotheses, the authors' responsibility for integrity, precision and accuracy of their work is paramount. The editor sees his role as a "chooser", and not a "changer": choosing to publish what are judged to be the best papers from those submitted.”
"traditional peer review can oblige authors to distort their true views to satisfy referees, and so diminish authorial responsibility and accountability"
ReplyDeleteHaving been on both sides of the process, I can appreciate the problems. There are reviews I participated in where I now think I should have come down less on behalf of the practical and communicative side, because it implicitly meant asking the authors to conform to the commonly understood paradigm. Sins of youth in overdoing it, perhaps.
But as they say, we all know that peer review is flawed, but it is hard to replace it. As the article shows...
stone-age women killed off their hairy children and kept the hairless ones and that's why we don't have hair? It's a joke, right?
ReplyDelete"Bold thinking" indeed.
More like "bald" thinking.
I would have thought that the most likely explanation for our comparitive hairlessness was the "aquatic ape" theory - how is that doing at the moment?
ReplyDeleteIt is a valid question, and I certainly haven't heard a sensible answer so far ....
Actually it seems to me a reasonable theory to consider, although I suspect it isn't going to pan out. Based on my own observation of mothers over the years I think it's doubtful that in general mothers give better care to their more attractive children over their less attractive children. My impression is that every mother typically considers her own children to be extraordinarily attractive, in other words that the mother-child bond trumps any cultural views about what is attractive. I suspect someone has actually studied that very topic and such research would obviously be useful in discussing this theory.
ReplyDeleteDawkins' hypothetical "green beard effect" from The Blind Watchmaker might be relevant. Hairlessness could be an example of runaway sexual selection, I've certainly heard women express a preference for non-hirsute males. As an extension of that concept we can consider the idea that females who make a preferential selection of a mate based on certain body characteristics might also make a preferential selection of which child to rear based on the same criteria.
Yup, as Tony pointed out this "journal" should really be named "Crazy-ass stuff the authors pulled out of their rear ends". So what do you expect?
ReplyDelete"Yup, as Tony pointed out this "journal" should really be named "Crazy-ass stuff the authors pulled out of their rear ends".
ReplyDeleteAnd if it's really, really crazy. they'll even give you a thousand pounds!
From a former comment of mine re the journal "Medical Hypotheses": Note that Medical Hypotheses is a non-peer reviewed journal which has published many of "aquatic ape" proponent Marc Verhaegen's articles on a pay-to-publish basis. Given the poor quality of Verhaegen's stuff, I wouldn't give the journal, or its editor, much weight. The editor, BTW, is a proponent of the AAT/H.
ReplyDeleteI would have thought that the most likely explanation for our comparitive hairlessness was the "aquatic ape" theory - how is that doing at the moment?
You asked the right guy. :) My site on the subject is at Aquatic Ape Theory: Sink or Swim? I'm the guy (or villian, to AAT/H proponents :)). My site has been (and is being) used by various college courses, and I recently wrote an entry on the subject for the Sage Encyclopedia of Anthropology. Bottom line: the idea has been argued, by every one of its proponents so far, with false information, altered quotes, claims that researchers said the exact opposite of what they actually did say, and basically, tactics reminiscent of creationists, which is sad. It doesn't make sense (the best pages on my site for why that is would be the "General problems with the AAT/H" and the "Summary", I'd think). Other pages deal with the various proponents' work.
It is a valid question, and I certainly haven't heard a sensible answer so far ....
It's pretty clear that the way our hair is now is due to sexual selection; it has all the classic earmarks: condition varies in different populations, varies between male and female, with major variation happening right at puberty. The fact that hair can change easily and quickly (it's due, apparently, to one or a very few genetic changes) does make it harder to tell more than that, although there's always the possibility of figuring out ways to see, for instance, just when it changed. The stuff with lice recently might help with that, and I wouldn't be surprised if someone figured out a way to tell from biochemistry and fossils just what happened and when, like we now can do to a limited extent with australopithecine diet.
anthrosciguy says,
ReplyDeleteIt's pretty clear that the way our hair is now is due to sexual selection; it has all the classic earmarks: condition varies in different populations, varies between male and female, with major variation happening right at puberty.
It's not clear at all. Our relative "hairlessness" may not even be an adaptation. It may just be an accident that arose by random genetic drift due to a bottleneck in an ancient population, or it may be a secondary effect of selection for sexual maturity at an earlier stage of development (paedomorphosis, sometimes called neoteny).
Okay. How would that produce the radical differences between males and female and the fact that these changes happen right at puberty?
ReplyDeleteAlthough I'm no expert, I've never heard of "parental selection" before, and find it an interesting concept. As an explanation for these particular traits, it may be just another "just so" story, but it does illustrate how it might work in particular circumstances.
ReplyDeleteKeep in mind that at the time human populations were mobile hunter-gatherers, and child spacing was important: too close and the mother is lugging two children around; too spread apart and the jones next door out-reproduced you. Based on modern "primitive" cultures, infanticide is clearly not an unheard of practice.
The physical features of a later born child arriving just before the optimal gap might influence the mothers decision.
I'll also caution against blithely dismissing this author. Anyone familiar with the initial reception of "The Nurture Assumption" knows what I mean.
I heard that in chimpanzees, some time before birth, the distribution of hair of the fetus is similar to that of adult humans: hair only on the head, and pubis.
ReplyDeleteI have never seen a photograph though, and can't remember references. If anyone can confirm this, please let us know.
If true, this is a quite plain deathblow to any hypothesis of sexual selection or other adaptationist speculation. It would be a quite clear secondary effect of paedomorphosis (as it is in several hairless paedomorphic mammals, other than humans)
"Based on my own observation of mothers over the years I think it's doubtful that in general mothers give better care to their more attractive children over their less attractive children. My impression is that every mother typically considers her own children to be extraordinarily attractive, in other words that the mother-child bond trumps any cultural views about what is attractive. I suspect someone has actually studied that very topic and such research would obviously be useful in discussing this theory."
ReplyDeleteI do recall reading that despite parental protestations, there was an observed bias in favor of attractive children. I don't know how valid this is, but here's the link:
http://www.uofaweb.ualberta.ca/prl/news.cfm?story=35170
"I heard that in chimpanzees, some time before birth, the distribution of hair of the fetus is similar to that of adult humans: hair only on the head, and pubis."
ReplyDeleteWell, a quick search (fetal development chimpanzee) does seem to confirm this:
http://natureinstitute.org/pub/ic/ic10/evol.htm
"For example, the skull of the newborn chimpanzee is remarkably humanlike (see figure), whereas the adult chimpanzee departs strikingly from the human form. Similarly, the hair on a chimpanzee fetus is, in humanlike fashion, restricted to the head, whereas the adult chimpanzee (like all other mammals except humans) is fully covered with hair. You could say, then, that humans tend to retain certain fetal traits."
There you go... where do the panglossian evopsychos disappear to when you dish out the good stuff?
ReplyDeleteHi all,
ReplyDeleteNice to see AAT mentioned here, but here's some serious information on the littoral theory of Pleistocene Homo (more correct term than AAT):
Homo trekked during the Pleistocene (exposed continental shelves) along the coasts & rivers to different continents & islands, not running over open plains as some PAs still believe.
The current opinion on AAT (with a totally different time-scale than Hardy's in 1960) can be found in a recent eBook edited by M.Vaneechoutte, A.Kuliukas & myself, with contributions of the late prof.Tobias, Elaine Morgan, Anna Gislén etc.: "Was Man More Aquatic in the Past? Fifty Years after Alister Hardy: Waterside Hypotheses of Human Evolution" Bentham Sci.Publ.2011.
Or google
- aquarboreal (on ape evolution)
- econiche Homo (on human evolution)
- pachyosteosclerosis (id.)
Or m_verhaegen@skynet.be