By Dave Wisker, Graduate Student in Molecular Ecology at the University of Central Missouri.
Creationists The Discovery Institute must have drooled when they heard a paper had been published by the respected journal, Animal Behaviour, which apparently reported that peahens did not prefer peacocks with more elaborate trains. Takahashi et al. (2008) appears to contradict several well-known studies that reported the opposite, and which have been cited as evidence for sexual selection in peafowl. Since the peacock’s tail is a venerable symbol of runaway selection for a secondary sexual trait, the DI ARN jumped on the story, crowing, with breathless excitement:
The alleged amazing powers of natural selection are much diminished as a result of these findings. The argument that it is “powerful enough” to maintain the feather display against the negative effects of attracting predators must be dropped. Furthermore, it appears not powerful enough to remove the display when it becomes an “obsolete signal”. Darwinists need to think very hard about the way they do science. This is a clear example of how a Darwinian hypothesis has become accepted as scientific fact, yet now has been disproved by some rigorous empirical research. This is a falsified prediction. This means that numerous textbooks and web sites need to be revised. More importantly, Darwinists should cease giving the impression that they have the keys to understand the natural world. So much of this ‘understanding’ is like peacock feathers - lots of show and no substance. Richard Dawkins extols Darwinism as a beautiful theory, but whenever we look closely, it fails to account for the observed data.
Unfortunately for the DI ARN, their enthusiasm for this paper may be premature, as I noted in a guest entry on Denis Ford’s “This Week in Evolution”. Essentially, the paper has two major problems (my article deals with some other minor ones as well):
- The authors used a different methodology to determine male reproductive success than the other studies, which makes comparing them very difficult. While the British and French studies measured male reproductive success by observed successful copulations, the Japanese one estimated the number of successful copulations, based on female pre-copulatory behavior.
- The genetic variance in tail morphology in all of the studies was very low (Takahashi et al.’s study had the lowest), which only magnifies the differences in methodology. Small differences in number of successful copulations have greater weight because the very low variation makes determining any kind of selection very difficult.
The main thrust of my article is that the differences in methodology for determining male reproductive success were magnified by the very low variance in the trait, invalidating comparison between the studies. It should be noted that Marion Petrie and Adriane Loyau, primary authors of two of the three major studies confirming peahen’s preference for more elaborate male trains, are in the process of publishing a reply to Takahashi et al’s paper. One wonders if the DI ARN will mention that.
I was reminded of how, in some species of pheasants, either Swinhoe’s, or Lady Amherst, the hens preferentially seek out males that have the longest spurs, and apparently don’t give much stock to plumage. In a study, researchers found that those pheasant cocks who had their spurs amputated mated with the fewest hens, while those pheasant cocks who had their spurs augmented with actual cowboy spurs mated with the most hens.
So that got me to thinking that perhaps now, during courtship, the peacock’s tail serves simply to identify to the female that he is an anxious suitor, and that, in turn, the peahen is more interested in other features of the male, such as his vocalizations or dances. Has anyone examined whether or not a peahen would attempt to mate with a tail-less peacock?
In birds of paradise, I saw footage of a male Greater Bird of Paradise attempt to woo what he thought was a female, but it turned out to be an immature male examining him too closely in order to learn the correct mating dancing procedure. So, perhaps fantastic male plumage may serve more important roles as species and gender recognition?
It might be worth pointing out that the resident expert who reviews evolutionary literature for the ARN blog is one Dave Tyler. Dave is an expert in textiles and has publications in such prestigious journals as Stitch World (seriously)
http://www.hollings.mmu.ac.uk/~dtyler/
Dave’s textiles experience provides him with the requisite background to not only shred evolutionary biology but also carve out a niche as a proponent of flood geology. Yup, he’s a young earth creationist. However he argues that most of the geologic record isn’t a record of the flood, but of the recovery from the flood, with the fossil record showing “recolonisation” by life. The flood occurred during the Pre-Cambrian. This revolutionary approach has resulted in important publications like:
Tyler, D., A post-Flood solution to the chalk problem, TJ 10(1):113, 1996.
This has earned him the ire of more mainstream YECs who accuse him of compromise:
http://www.answersingenesis.org/doc[…]nisation.asp
Nature News is reporting on another study into sexual selection (illustrated by the trusty peacock, of course), this time in yeast. The researchers claim that this allows them to accurately follow the spread of single alleles, something not possible in earlier studies.
http://www.nature.com/news/2008/081[…]08.1168.html
The paper in question is “D.W. Rogers & D. Greig, Proceedings of the Royal Society B, DOI:10.1098/RSPB.2008.1146 (2008)”. Perhaps a worthy subject of a future blog entry?
Dave Tyler says
This is a good example of Dave’s typically smug, self satisfied, slightly patronising style (which I’ve observed at online discussion fora). It’s also, I presume, utter bollocks. I imagine there are studies, empirical research, which supports sexual selection. The latest work may contradict some established notions, but that doesn’t mean that other research hasn’t been conducted on the subject.
So now I suppose we will see the DI sink millions into studies of peacock mating. After all, if they really thought that they were right about this, then shouldn’t they be trying to do the research themselves? Why let the “Darwinists” have all the glory of disproving a small example of sexual selection when they could become famous for it? Why assume that others will be able to break the conspiracy of silence when they cannot? Oh well, at least we know how this paper got published.
Of course , assuming that they were actually able to demonstrate something significant about peaock mating, that would only leave 5 million other examples of selection to deal with.
That would almost be like they really wanted to discuss the controversy.
If that were true, then I have delightful Nevada beachfront property to sell you.
I am going to take a stab at this, but I am not a statistician, so someone can comment if I screw it up. So they say that hens do not prefer cocks with elaborate plumage. So, I assume, (and this may be where I am wrong) that the null hypothesis was “there is no sexual selection for elaborate tail plumage”.…they did their analysis, and arrived at an insignificant P value, so they had to report there is no selection. However, technically, a significant P value would have allowed them to reject the null hypothesis and say that there is sexual selection for elaborate plumage.…but an insignificant P value DOES NOT PROVE THE NULL HYPOTHESIS TO BE TRUE…i.e. that hens do not really prefer elaborate plumage. Am I right or wrong about that?
To be accurate, the Access Research Network may not necessarily be the same as the Discovery Institute. Those two groups just happen to both support Intelligent Design. Dave Wisker might want to correct the entry above, lest the Disco dudes accuse us of libeling them.
Actually, I think that they would welcome a chance to show how the “Darwinian orthodoxy” is struggling to keep their dogma going in the face of the irrefutable facts. They could have their thorough misunderstanding of the rebuttal paper form the basis for their “evidence” that the “Darwinians” do not understand their own data. So far their “controversy” has been entirely of their own manufacture; I am surprised that they have not tried harder to inflate actual controversy to match their own. Then again, it is not too often that a legitimate scientific controversy (even one which appears to be fleeting, such as this one) comes along that involves one of their “icons”.
Feel free to slap me if this is in fact what they do. I would hate to think that I gave them ideas.
Hermit writes:
Right. More technically, the null hypothesis (in the case of eyespot number) is that any relationship between eyespot number and male reproductive success is what we would expect if the relationship was entirely due to chance. That is what the Japanese data led them to conclude.
Right again. In this particular case, Takahashi et al were unable to reject the null hypothesis, which does not mean the null is automatically true.
Dale writes:
Oh dear, you’re right! I keep forgetting–when looking at ARN’s ‘Featured Authors” link– that there may be other Michael Behes and Paul Nelsons and William Dembskis and Mark Hartwigs and Charles Thaxtons in this world that aren’t DI Fellows.
Hmmm. But weren’t flowering plants created along with gymnosperms on Day Three of Creation Week, before the Flood?? So shouldn’t we see angiosperms and gymnosperms together in every layer? Why do we have to wait until the Cretaceous before flowering plants show up?
Probably the main point to consider in the Discovery Institute’s pea fowl fiasco is that natural selection is a given. If any of their fellows deny the existence of natural selection in nature they are the basket case types. Even Wells likely acknowledges that natural selection is a fact of nature. This is all just smoke. It is just part of their general obfuscation scam. It is really pointless for them to argue it, but they do it anyway because the rubes can be fooled and lied to about it.
There is no way that they can deny that natural selection is a fact of nature, so all the smoke is to confuse the ignorant into thinking that the argument is about something else. It is just the general strategy of the dishonest switch scam that they are currently running on any rube stupid enough to have believed them about the “science” of intelligent design.
If they actually had any valid arguments they wouldn’t be rambling on about pea hens.
Ron Okimoto
That’s not exactly what I meant. You know how internet users will create sock puppets to make a false impression of popularity for their extremist views? Well, the ARN may indeed merely be a front group for the Disco dudes, and not an independent organization. But it’s also possible for Dembski, Behe, and others to belong to both groups, even if they are of independent origin. Never assume, always verify.
Well, this is ironic:
First, meteorologists are not wrong “all the time”, it’s just that the chaotic element in weather patterns make it almost impossible to make accurate forecasts more than a couple of weeks in advance. Second, it is ludicrous to think that an expert on WEATHER could think himself able to challenge experts on EVOLUTION. I’m no expert on art, so I keep my mouth shut around professional artist and art critics! Finally, cosmic and life’s origins are not the same as evolution. Sigh!
Well, I seem to have missed out, by just a few years, on my chances to buy beach-front anywhere else. So why not. Just send me your bank account details and I’ll send you your money.
Thanks for making the corrections, Dave Wisker.
And now for something extra special:
Indeed … when we all know that meteorology is corrupted by atheistic materialism! Does Magnuson ever say that storms are the products of Divine wrath, as scripture says they are?! Obviously he’s playing both sides of the fence into order to introduce his materialistic agenda to an unsuspecting public!
But we’re not fooled. We see through his game.
White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html
If anti-Evolutionists are so down on the power of selection among competing agents to bring about general improvement, and simultaneously so up on an overarching intelligence guiding things behind the scenes, why do most of them seem to align with political ideologies that champion a free-market?
… you are conflating many, many things here. and who are these anti-evolutionists. I think there a very few people if any that do not believe evolution happens?
Where’s FL?
I’ve often wondered the same thing, but the more I watch the behavior of those ideologues, the more I’m convinced their belief in the free market is no more rooted in sound science than is their belief in whatever version of creationism they espouse. In both cases it seems driven mostly by an extreme aversion to having outside authorities tell them what they can and can’t do, even going so far as to deny the legitimacy of those authorities, whether it be duly elected politicians, or rigourously tested scientists. All pathetic detail aside, they simply want to believe what they believe.
Correction, Sci, they believe what they have been told to believe, and they have been taught what they are supposed to want to believe.
The troll of many names, known currently as cobby, is here. What more could FL do to make creationist bigotry look stupid?
Stanton said:
Everyone knows that cowboy pheasants are the baddest.
I’m not aware of any, but I am not an ethologist. I initially looked into this subject from an interest in how populations lose variation, and also from familiarity with a fellow grad student’s research into lekking species (in her case, the Greater Prairie Chicken).
ARN was started by guys associated with the Discovery Institute. Guys like Meyer are, or at least were, on the board of directors of ARN. When it was started it looked like a place where the ID perps could sell their junk and create a discussion group that they had more control over. It was probably supposed to be a laymans ISCID.
@SteveF “Dave Tyler. Dave is an expert in textiles and has publications in such prestigious journals as Stitch World…”
Is that why he keeps us in stitches?!
Adeline Loyau and Marion Petrie have published their reply in Animal Behaviour (the “Forum” section):
Loyau A, M Petrie, M Saint Jalme, and G Sorci (2008). Do peahens not prefer peacocks with more elaborate trains? Animal Behaviour 75(5): e5-e9
They make one very important point (which David Tyler should especially note):
So, one of their biggest claimed advantages turns out to be not so great after all.
They also comment on the low variation (Dale Husband should appreciate this):
Dave,
Yours is a great post. I’m not surprised that a YEC like Tyler would miss the statistical implications. As for your recent replies, I am glad you’ve emphasized the importance of sample size, which Tyler has clearly missed.
Appreciatively yours,
John
Indeed, I do. Thank you for the excellent smackdown! :)
FL, in a comment on the other peacock thread, writes:
FL quotes from the press release:
My question to FL is, why is this ”important”? Loyau and Petrie, in their response to Takahasi et al’s paper, comment:
Sort of on topic; check out the display feathers on this dinosaur at Tet Zoo
I’ve often wondered why the IDIOTs bother with these sorts of articles. Anybody with half a brain and an open mind knows they’re wrong, a priori; the choir neither understands, nor cares. So, what’s the point? 42?
As has been stated so often here, if the IDIOTs really wanted to change minds, they’d do the research.
Randy
Ah, but the trouble with research is that it’s apt to produce conclusions that weren’t what the researcher was looking for.
My question to FL is, why is this “important”?
It’s not even relevant, frankly.
the mechanism of what causes the plumage changes is interesting, but simply isn’t relevant as to whether or not it is an example of sexual selection.
I guess whenever these morons see the word “sex”, they think that necessitates it must be related to the physiology of sex itself.
sexual selection is merely a subset of natural selection, where mate choice acts as the selective pressure instead of predation or competition, etc. There’s nothing that necessitates the physiological mechanism of how mate choice acts on a trait to be in any way related to sexual physiology itself.
this is the problem when debating these moronic creationists. They know so little of how biological systems actually work, that their responses often fall in the “not even wrong” category.
And as such, they are taught that wanting to learn things that their spiritual handlers don’t want them to know is forbidden, under pain of eternal damnation.
It doesn’t help FL that he takes smug pride in the fact that he not only doesn’t like learning things, but that it is his sacred duty not to learn.
It is more another example of a common type of creationist argumentation– every paper that even hints at contradicting evolution or some aspect of evolution is “important”, or ‘groundbreaking”, or some other superlative. Every creation ‘scientist’ is always a “leading scientist” or “brilliant”. Any biologist who is quote mined, no matter how obscure, wrong-headed, or stupid is festooned with creato-superlatives. To creationists, its all shinola.
To creationists, its all shinola.
yeah, they do like to project, don’t they?
still, my point is that there is little reason to even waste time repeatedly refuting the “not even wrong” stuff. doing so just plays their game.
all one need do in a forum like this is simply link to the correct information for those who actually wish to learn. honest questions coming from that are then worth answering, but we never see these from creationists.
so when someone like the ridiculous FL spouts off, he’s so far wrong it’s simply not worth the effort to engage. rather, just post a link to a decent review of the current knowledge on the subject, and either ignore or boot the morons.
for sexual selection, there was a good review article published just a couple of years back in TREE:
http://www.sciencedirect.com/scienc[…]d80f60f0bb5a
I know it requires a purchase if you don’t have access to a library (or a subscription to TREE - which I would highly recommend), but if one is really interested in the subject, it’s worth the effort and dollars to get and read the article.
which of course lets me put in yet another plug for open source journal efforts.
http://www.doaj.org/
and there are at least a few freely accessible worthwhile articles on the subject, too:
http://www.doaj.org/doaj?func=searc[…]=&f2=all
The lady doth protest too much, methinks.
Which lady?
I’m going to respectfully disagree here. My main reason for posting is not to engage FL and his ilk necessarily, but also to help those laymen who don’t have access to the papers being discussed, or who are unfamiliar with the terminology and concepts, to understand the material and arguments (whether I’m any good at it may be debatable). For them, knowledge is power, and hopefully they will see for themselves just how weak and disingenuous creationist arguments are. Simply tossing them a link isn’t much help, in my view.
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