Pavo cristatus

Unfortunately, feeding the blue chicken with pop rocks and soda turned out to be a terrible mistake.

http://tinyurl.com/2kxyc7

Hey baby... how you doin'?

I'd say the eyes have it.

NPD said: Hey baby... how you doin'?

I don't know if it's mating songs or territorial calls or what, but peacocks have got to be the loudest of domestic birds. Their calls can be extremely annoying.

Here's its page on the Tree-of-Life website:
http://tolweb.org/Pavo/57452

Too bad humans don't have nearly so much to work with. We have no tails!

My first reaction - OOoooooohhh!

I had 3 peacocks on my roof a couple of weeks ago - that was a surprise! :-)

KTH said: Too bad humans don't have nearly so much to work with. We have no tails!

Paul Burnett said: I don't know if it's mating songs or territorial calls or what, but peacocks have got to be the loudest of domestic birds. Their calls can be extremely annoying.

Keep up the great photos about the animals (and other organisms) that evolution "created."

Peacocks make sense as a result of sexual selection, but certain not by intelligent design.

a lurker said: Peacocks make sense as a result of sexual selection, but certain not by intelligent design.

Spectacular!

Thanks for posting this.

Did the peacock deliberately choose this background?

How long did it take to evolve? An atom, a molecule, or a feature (e.g. feather) at a time?

“OK, so why would a DESIGN process produce organisms with life-threatening ornaments?

... the same reason we have poodles and siamese cats.

jobby: I hope you are not suggesting that God (or whoever is your Intelligent Designer) is just as worse a Designer than we humans (sometimes) are. Blasphemy!

Eddie Janssen said: jobby: I hope you are not suggesting that God (or whoever is your Intelligent Designer) is just as worse a Designer than we humans (sometimes) are. Blasphemy!

Peacocks make sense as a result of sexual selection

"This is a falsified prediction. This means that numerous textbooks and websites need to be revised." ---- David Tyler, ARN

FL said:

Peacocks make sense as a result of sexual selection

Not anymore. In fact, "Peahens do not prefer peacocks with more elaborate trains," as Takahashi et al wrote last April in the journal Animal Behavior. Peacocks no longer constitute evidence of evolution via sexual selection.

"This is a falsified prediction. This means that numerous textbooks and websites need to be revised." ---- David Tyler, ARN

******** You guys better go hire a new poster boy (or in this case, poster bird) for the religion of evolution, because THIS one has definitely flown the coop!!! For more details, go to: http://www.arn.org/blogs/index.php/literature/2008/04/01/sexual_selection_falsified_in_the_case_o FL :)

Surely you guys are not going to allow this vile exhibitionist to pollute yet another thread with his inane flatulence.

Science Avenger said: Surely you guys are not going to allow this vile exhibitionist to pollute yet another thread with his inane flatulence.

iml8 said: Actually, Phil Johnson pointed to the peacock's tail as a disproof of Darwinism, asking why evolutionary selection would produce organisms with life-threatening ornaments.

Pavo Cristatus? Isn't he one of the Three Tenors?

Since male peacocks appear to shiver in response to female run-arounds, the scientists think that male mating calls, which consist of multiple notes and sound very different than the noises females make, could affect mating success. The trains, on the other hand, may just be obsolete signals at this point, they suggest. Louise Barrett, a member of the Faculty of Science and Technology at the University of Central Lancashire in Preston, U.K., thinks the reason for their obsolescence could be that, unlike many other elaborate traits in birds and animals, peacock trains are dictated by the female hormone estrogen, rather than testosterone. Barrett said that "it is the absence of estrogen in the male that produces the train, rather than the presence of testosterone." "Traits under the control of estrogen are usually very poor indicators of phenotypic (visible physical attributes) and genotypic (DNA) condition," she explained. "Accordingly, females are known to disregard estrogen-dependent male plumage cues when choosing mates." Barrett, however, mentioned that this theory, along with the rest of the new findings, is bound to be controversial, since other researchers have presented data suggesting that a peacock's train does influence whether or not a female will choose to mate with him.

and http://blog.lib.umn.edu/denis036/thisweekinevolution/2008/06/guest_blogger_the_peacocks_tal.html

jobby:

"a not unfeasible scenario is that some super intelligence was tinkering with the DNA to see what beautiful, curious and interesting creatures could arise. to completely dismiss this without overwhelming evidence is not science."

Obviously you are not referring to God. God knows how a peacock's tail will look like when He (God, not the peacock) has some fun with the A's, G's, T's and C's (God does not tinker; according to my English-Dutch dictionary "to tinker" means something like doing a bad job).
Maybe God (excusez-moi: some super intelligence) gave women **** (i am looking for a decent word here) for the same reason...

They can’t be too life-threatening, because peacocks do in fact exist in the wild

. ... Then how would we know when and if a secondary sexual characteristic becomes too life threatening and outweighs its mating advantage??

Eddie Janssen said: jobby: "a not unfeasible scenario is that some super intelligence was tinkering with the DNA to see what beautiful, curious and interesting creatures could arise. to completely dismiss this without overwhelming evidence is not science." Obviously you are not referring to God. God knows how a peacock's tail will look like when He (God, not the peacock) has some fun with the A's, G's, T's and C's (God does not tinker; according to my English-Dutch dictionary "to tinker" means something like doing a bad job). Maybe God (excusez-moi: some super intelligence) gave women **** (i am looking for a decent word here) for the same reason...

Once again, FL demonstrates his poor reading comprehension, and also demonstrates that he has never actually observed live peafowl, either, otherwise, he would have realized that he is making a fool of himself, yet again.

People fail to realize that the sexual characteristics a female bird looks for won't necessarily be painfully obvious to a human observer, such as the fact that in some species of pheasants, the hens prefer to mate with males that have the longest spurs, as opposed to those with the most fabulous plumage.

Likewise, even if peahen do not actively select for males with the biggest trains (the actual tail feathers of the peacock serve to erect what we think of as the tail), peacock trains do play an indirect, albeit crucial role in sexual selection, in that peacocks use their trains in order to intimidate their rivals, and thus, deny lesser males access to the local peahens, and limiting the peahens' choices to only those males with the biggest trains, as all of the males with dinky trains will have scared away.

jobby said: (snip) a not unfeasible scenario is that some super intelligence was tinkering with the DNA to see what beautiful, curious and interesting creatures could arise. to completely dismiss this without overwhelming evidence is not science.

To avoid this real work is not science, it is cowardice.

jobby

.. or it could be evolution.
I think Ockham would pick evolution.

fnxtr said: To avoid this real work is not science, it is cowardice.

joby said: They can’t be too life-threatening, because peacocks do in fact exist in the wild . ... Then how would we know when and if a secondary sexual characteristic becomes too life threatening and outweighs its mating advantage??

FL said:

Peacocks make sense as a result of sexual selection

Not anymore. In fact, "Peahens do not prefer peacocks with more elaborate trains," as Takahashi et al wrote last April in the journal Animal Behavior. Peacocks no longer constitute evidence of evolution via sexual selection.

"This is a falsified prediction. This means that numerous textbooks and websites need to be revised." ---- David Tyler, ARN

******** You guys better go hire a new poster boy (or in this case, poster bird) for the religion of evolution, because THIS one has definitely flown the coop!!! For more details, go to: http://www.arn.org/blogs/index.php/literature/2008/04/01/sexual_selection_falsified_in_the_case_o FL :)

Eddie Janssen said: jobby .. or it could be evolution. I think Ockham would pick evolution.

Then a not unreasonable expectation is that those who hold this position explain when and how which designer did what. Or least make an attempt.

.... seems the cambrian explosion was a time of intervention also when the first cell appeared. a super intelligence beyond what we can comprehend fully. not human, not even close to human is the most likely. however there is a possibility that it also could have been on the level of humans but ahead of us time wise about 500 million years

Occam's Razor doesn't apply, because ID doesn't make predictions that have explanatory power, certainly not equal explanatory power.

However, even if we entertained the comparison for the sake of the Razor, we are essentially comparing evolution and evolution+designer. I'm basing that on the fact that Behe admits that not all natural features are "designed" but probably evolved naturally, so we are working with a system that includes the whole of evolution plus invokes the Designer. The fact that a small number of hand-picked systems are alleged to have been Designed rather than to have evolved does not cancel out the complexity added to the system by invoking this mysterious extra-natural agency.
So if we were able to apply the Razor, ID wouldn't make the cut.

Occam’s Razor doesn’t apply, because ID doesn’t make predictions that have explanatory power, certainly not equal explanatory power.

.... what predictions does Darwinism make??

The fact that a small number of hand-picked systems are alleged to have been Designed rather than to have evolved does not cancel out the complexity added to the system by invoking this mysterious extra-natural agency. So if we were able to apply the Razor, ID wouldn’t make the cut.

.... if we use that logic then the theory that people with red have bad tempers is a better theory than some people with red hair are genetically predisposed but also the childhood environment is a factore.

... sorry charlie: no cigar!

They can’t be too life-threatening, because peacocks do in fact exist in the wild

. … Then how would we know when and if a secondary sexual characteristic becomes too life threatening and outweighs its mating advantage??

When those individuals that have these secondary sexual characteristics die out while producing fewer or no young.

........... but how do we know it is not another concommitant factor??

They can’t be too life-threatening, because peacocks do in fact exist in the wild

... here is the circular logic. we have an unusal seemingly non-adaptive feature: the large train. according to Darwinism features appear because they make a survival advantage

do we know that peacocks with smaller trains have less offspring?? or is it just FAITH in Darwinism that leads us to believe that???

jobby said:

" ... seems the cambrian explosion was a time of intervention when the first cell appeared."

You seem to be a little out of date. Clearly identifiable fossils exist in the Precambrian (try Googling Edicaria) or look out for Charnia masoni (probably a seapen - a kind of soft coral) from Charnwood Forest, England). 3 species of Charnia are known, the first (C. masoni) having been discovered in 1957. Specimens of one of the 3, Charnia wardii, have been found over 2m long!

Or, try reading Brasier, M., McLoughlin, N., Green, O., and Wacey, D. (June 2006). "A fresh look at the fossil evidence for early Archaean cellular life" (PDF). Philosophical Transactions of the Royal Society: Biology 361 (1470): 887–902. doi:10.1098/rstb.2006.1835.

I retrieved this today so there is no excuse for not being able to find out.

This suggests that there is evidence for life going back to 3 Ga and maybe further. Others have suggested that life first began shortly after (maybe within 100 Ma or so) after the Late Heavy Bombardment around 3.8 Ga.

However good or well meaning your arguments are, you will never get support from a site like this until you get up to date.

Jobby: simple question. Are you a raelian?

Takahashi’s group noted that females who perform multiple “run-around” behavior for a male often accept that male for copulation later, so they considered any female who performed more than two successive run-arounds for a male as having made a “preferred visit”, and counted that as a successful copulation. This could be a crucial source of error, if a significant number of females performed multiple run-arounds but did not accept the male for copulation later, or if they copulated after less than three run-arounds. It’s certainly worth investigating separately.

The Japanese authors also discuss other factors that may explain the different conclusions, namely sample size, length of study, and the age of the males involved. The advantage their study has over the others is the number of individuals (around twice that of the others), length of the study and the range of ages of the males. It is not clear, however, if those factors contributed significantly to the results.

(Takahashi)'s conclusion is effectively "We do not know the origin or original function of the peacock's tail, but we think it originated a long time ago."

Likewise, even if peahen do not actively select for males with the biggest trains (the actual tail feathers of the peacock serve to erect what we think of as the tail), peacock trains do play an indirect, albeit crucial role in sexual selection, in that peacocks use their trains in order to intimidate their rivals, and thus, deny lesser males access to the local peahens, and limiting the peahens’ choices to only those males with the biggest trains, as all of the males with dinky trains will have scared away.

Alan B said: jobby said: " ... seems the cambrian explosion was a time of intervention when the first cell appeared." You seem to be a little out of date. Clearly identifiable fossils exist in the Precambrian (try Googling Edicaria) or look out for Charnia masoni (probably a seapen - a kind of soft coral) from Charnwood Forest, England). 3 species of Charnia are known, the first (C. masoni) having been discovered in 1957. Specimens of one of the 3, Charnia wardii, have been found over 2m long! Or, try reading Brasier, M., McLoughlin, N., Green, O., and Wacey, D. (June 2006). "A fresh look at the fossil evidence for early Archaean cellular life" (PDF). Philosophical Transactions of the Royal Society: Biology 361 (1470): 887–902. doi:10.1098/rstb.2006.1835. I retrieved this today so there is no excuse for not being able to find out. This suggests that there is evidence for life going back to 3 Ga and maybe further. Others have suggested that life first began shortly after (maybe within 100 Ma or so) after the Late Heavy Bombardment around 3.8 Ga. However good or well meaning your arguments are, you will never get support from a site like this until you get up to date.

jobby said:

Alan B said: jobby said: " ... seems the cambrian explosion was a time of intervention when the first cell appeared." You seem to be a little out of date. Clearly identifiable fossils exist in the Precambrian (try Googling Edicaria) or look out for Charnia masoni (probably a seapen - a kind of soft coral) from Charnwood Forest, England). 3 species of Charnia are known, the first (C. masoni) having been discovered in 1957. Specimens of one of the 3, Charnia wardii, have been found over 2m long! Or, try reading Brasier, M., McLoughlin, N., Green, O., and Wacey, D. (June 2006). "A fresh look at the fossil evidence for early Archaean cellular life" (PDF). Philosophical Transactions of the Royal Society: Biology 361 (1470): 887–902. doi:10.1098/rstb.2006.1835. I retrieved this today so there is no excuse for not being able to find out. This suggests that there is evidence for life going back to 3 Ga and maybe further. Others have suggested that life first began shortly after (maybe within 100 Ma or so) after the Late Heavy Bombardment around 3.8 Ga. However good or well meaning your arguments are, you will never get support from a site like this until you get up to date.

... These studies do not give evidence of no intervention. What point are you trying to make??

jobby said: They can’t be too life-threatening, because peacocks do in fact exist in the wild ... here is the circular logic. we have an unusal seemingly non-adaptive feature: the large train. according to Darwinism features appear because they make a survival advantage do we know that peacocks with smaller trains have less offspring?? or is it just FAITH in Darwinism that leads us to believe that???

Jobby said:"seems the cambrian explosion was a time of intervention also when the first cell appeared"

seems the cambrian explosion was a time of intervention also when the first cell appeared.

— Jobby

Okay let's start with the work of Valentine "On the Origin of Phyla". Up for it? Let me warn you

1. It's a book
2. It's a big book
3. It's a big book with big words
4. It's a big book with big words in small print

What do you say? Interested in discussing Valentine

PS: How familiar are you with the pre-cambrian, it's life forms and the data?

Surprise us.

"seems the cambrian explosion was a time of intervention also when the first cell appeared"

I apologize for the misquote - it was an honest mistake because your words could be taken to mean exactly what I thought you said and I notice that others took them the same way as I did. Having said that, I do object to being called "slimey" (you know nothing at all about me) and I am surprised that you find it necessary take the name of the Lord Jesus Christ in vain. Do you have scriptural support for that?

Unfortunately, as others have suggested, your use of English was poor. It strongly implied that you considered the Cambrian explosion also to be when the first cell appeared.

You will run into criticism if you go in for the hit and run tactics and are not clear in what you say. But then, you know that, don't you?

Incidentally, have you read any of the material I quoted?

To take it further, what form did the "intervention" take that you are so keen on? Who did what, how and when? Do you have any substance in your ideas? Do you have any evidence? You are on a site where science is being discussed. Are you talking science or would you be happier on a religious site?

Sorry, jobby, your time is up.

It may be late afternoon your time but in the UK it is after 11 p.m. and I need a reasonable night - exam on Wednesday. I am what they laughingly call a "mature student".

I'll be back tomorrow if you have anything useful to say. Best wishes to all.

FL said: Hey Stanton, it's only natural that you guys would want to conduct some Damage Control after a gig like Takahashi's. I certainly don't fault you for that. However, the fact remains (as Wisker's blog makes clear; thanks to fnxtr for providing it), that Takahashi et al actually hasn't been overturned by anybody. That previous studies existed (Petrie, Petrie and Williams, Loyau) that support peacock sexual selection is not a surprise; indeed Wisker points out that THEY are the "conventional wisdom" that Wisker admits is "challenged" by the Takahashi paper. (You did see that word "challenged" in there, right Stanton?) Stated simply, Wisker would like to be able to negate that challenge but is forced to heavily qualify his potential objections for now. He can't overturn or refute anything at this time. Example:

Takahashi’s group noted that females who perform multiple “run-around” behavior for a male often accept that male for copulation later, so they considered any female who performed more than two successive run-arounds for a male as having made a “preferred visit”, and counted that as a successful copulation. This could be a crucial source of error, if a significant number of females performed multiple run-arounds but did not accept the male for copulation later, or if they copulated after less than three run-arounds. It’s certainly worth investigating separately.

In the following example, Wisker admits a certain advantage of the Takahashi study. As you'd expect, he attempts to cast doubt at the end of it, but a mere "it is not clear" is as far as he can go. He can't overturn or refute anything at this time.

The Japanese authors also discuss other factors that may explain the different conclusions, namely sample size, length of study, and the age of the males involved. The advantage their study has over the others is the number of individuals (around twice that of the others), length of the study and the range of ages of the males. It is not clear, however, if those factors contributed significantly to the results.

In the end, Wisker simply states his preference for Petrie's views (the "conventional wisdom") while talking about "more research questions" and "further investigation". And all that's to be expected. However....that does not overturn the challenge posed by Takahashi. Y'all are just not there yet. Wisker wants to say "The creationists' dream is just that" but right now, he doesn't ***know*** that. He's just hoping. Meanwhile, you still got Takahashi on the table, as yet unrefuted. Like David Tyler said,

(Takahashi)'s conclusion is effectively "We do not know the origin or original function of the peacock's tail, but we think it originated a long time ago."

Some will remain unconvinced of the challenge on the table. Some will insist that peacock feathers ARE evidence of evolution via sexual selection ("the conventional wisdom") no matter what's on the peer-review science-journal table right now. That's fine. Be it evolution or Christianity, people are generally loathe to give up even a fraction of their chosen religion. Me too. But the honest pro-science approach to take, actually would be to insist that those in charge, go ahead and revise those textbooks and websites to at least reflect the challenge presented by Takahashi's 2008 article. FL :)

Have you naysayers considered that the reason peahens are not impressed by peacocks' massive tail feathers is because ALL peacocks have them? If all men were three meters (nine feet) tall, being three meters tall would be no big deal to women. There would have to be something new and unusual, such as having blue hair as well, to make the man stand out and attract more mates than other three meter tall men. Meanwhile, men shorter than average would tend to lose out. Likewise, while the first peacocks with enlarged tail feathers would have stood out and attracted more mates, over time the genes for extremly long and complex tail feathers has become universal in the peafowl genome, thus negating the original attraction of the massive feathers. Now, it is only the peacocks that happen to lack the massive tail feathers that do not attract mates. Thousands or millions of years ago, peacock tail feathers were a big deal, but not today.

Those Japanese scientists look incompetent. The proper way to test the attractiveness of peacock tail feathers is to:

1. Select a population of peafowl from the wild and take them captive.

2. Right before the peafowl mating season, cut off the tails of about half the males.

3. Observe how many ACTUAL MATINGS occur between unaltered males and females, and also the number of ACTUAL MATINGS between altered males and females.

4. Record the results.

5. Publish the results.

Was this done here? Appearantly NOT!

http://dsc.discovery.com/news/2008/03/26/peacock-feathers-females.html

Thus, FL's arrogant assertions are debunked!

FL has brought up some points from my guest blog on the Takahashi et al article. The biggest problems I have with their study is their failure to use the same methodology in determining male reproductive success. This becomes critical when one considers how low the variance in tail morphology is in all of the studied populations. The Takahashi population had the lowest variance of all of them. If variation is very low for the trait under examination, then it will be very difficult to determine if selection is happening at all. Use of a different methodology than the other groups only compounds the problem.

Another issue concerning the low variance is the factors which contribute to it. While it is true that sexual selection can be expected to reduce genetic variance in the trait, other factors not directly related to female prefernce can make significant contributions as well. Firstly, lekking species typically show highly skewed sex ratios, which reduce the effective population size. Reduced effective population sizes sap genetic diversity. Secondly, in some bird species (peafowl being one of them), males on the lek are often closely related. This increases the inbreeding coefficient for the population, which also reduces the pool of genetic diversity. Finally--and perhaps more importantly--in all of the studies, the populations were very small and isolated, giving stochastic processes, such as genetic drift, more opportunity to reduce the variance. RA Fisher pointed out that, as the genetic variance for a trait decreases, so do its selective benefits. This could explain the weak correlations in the positive studies, as well as the negative results Takahashi et al reported. However, if the variance was reduced significantly by genetic drift as an artifact of the size of the studied populations, then Takahashi's paper has NOT demonstrated that peahens do not prefer males with more elaborate trains. They have not ruled out this possibility, therefore FL is foolish to suggest that their conclusions should replace the common wisdom. His suggestion is, in fact, anti-scientific.

Dave WIsker said: FL has brought up some points from my guest blog on the Takahashi et al article. The biggest problems I have with their study is their failure to use the same methodology in determining male reproductive success. This becomes critical when one considers how low the variance in tail morphology is in all of the studied populations. The Takahashi population had the lowest variance of all of them. If variation is very low for the trait under examination, then it will be very difficult to determine if selection is happening at all. Use of a different methodology than the other groups only compounds the problem. Another issue concerning the low variance is the factors which contribute to it. While it is true that sexual selection can be expected to reduce genetic variance in the trait, other factors not directly related to female prefernce can make significant contributions as well. Firstly, lekking species typically show highly skewed sex ratios, which reduce the effective population size. Reduced effective population sizes sap genetic diversity. Secondly, in some bird species (peafowl being one of them), males on the lek are often closely related. This increases the inbreeding coefficient for the population, which also reduces the pool of genetic diversity. Finally--and perhaps more importantly--in all of the studies, the populations were very small and isolated, giving stochastic processes, such as genetic drift, more opportunity to reduce the variance. RA Fisher pointed out that, as the genetic variance for a trait decreases, so do its selective benefits. This could explain the weak correlations in the positive studies, as well as the negative results Takahashi et al reported. However, if the variance was reduced significantly by genetic drift as an artifact of the size of the studied populations, then Takahashi's paper has NOT demonstrated that peahens do not prefer males with more elaborate trains. They have not ruled out this possibility, therefore FL is foolish to suggest that their conclusions should replace the common wisdom. His suggestion is, in fact, anti-scientific.

Sheesh! Are you implying I did a poor job because I didn’t use enough big words?!

Those Japanese scientists look incompetent. The proper way to test the attractiveness of peacock tail feathers is to: 1. Select a population of peafowl from the wild and take them captive. 2. Right before the peafowl mating season, cut off the tails of about half the males. 3. Observe how many ACTUAL MATINGS occur between unaltered males and females, and also the number of ACTUAL MATINGS between altered males and females. 4. Record the results. 5. Publish the results. Was this done here? Appearantly NOT!

Dave WIsker said: This only tests female preference for males with tails. It does not address female preference for more elaborate trains.

Dave Wisker said:

Sheesh! Are you implying I did a poor job because I didn’t use enough big words?!

Not at all. Is your self-esteem so low that a more fleshed out explanation in reply to someone citing my article threatens you? Or is your ego so immense that you can tolerate no further examination of the subject once you addressed it?

When you say “female preference for more elaborate trains,” is that to say that they prefer steam locomotives or bullet trains, or anything with fancy dining cars and separate sleeping compartments?

Please excuse Mr Husband, Dr Wisker

he uses facetiousness to mask the pain of his caffeine addictions.

Dave WIsker said:

Sheesh! Are you implying I did a poor job because I didn’t use enough big words?!

Not at all. Is your self-esteem so low that a more fleshed out explanation in reply to someone citing my article threatens you? Or is your ego so immense that you can tolerate no further examination of the subject once you addressed it?

Dave WIsker said: This only tests female preference for males with tails. It does not address female preference for more elaborate trains.

I just get annoyed at those who come across as smarter than everyone else. Then I realized who you were and thus my mistake. My apologies for stepping all over your territory.

Dave WIsker said: Dale husband writes:

Those Japanese scientists look incompetent. The proper way to test the attractiveness of peacock tail feathers is to: 1. Select a population of peafowl from the wild and take them captive. 2. Right before the peafowl mating season, cut off the tails of about half the males. 3. Observe how many ACTUAL MATINGS occur between unaltered males and females, and also the number of ACTUAL MATINGS between altered males and females. 4. Record the results. 5. Publish the results. Was this done here? Appearantly NOT!

This only tests female preference for males with tails. It does not address female preference for more elaborate trains.

do we know that peacocks with smaller trains have less offspring?? or is it just FAITH in Darwinism that leads us to believe that???

Reproduction is costly and individual decisions about when and how much to invest in reproduction will relate to potential benefits in terms of offspring survivorship or mating success. For those organisms that can reproduce more than once, individuals should invest relatively more in reproduction when the potential benefits are high. If females gain directly or indirectly from choosing attractive, highly ornamented males, then it could be predicted that females mated to these males should invest more in reproduction. Here we report the first test of this prediction for a lekking species, peafowl (Pavo cristatus), in which males do not provide resources for offspring, and females prefer to mate with those males that possess the most elaborate trains. We find that peahens randomly mated to males that vary in the degree of ornament produce more eggs for those peacocks with more elaborate trains. We could find no evidence to support the possibility that this difference arises as a result of difference between males in their ability to fertilize eggs.

… and exactly what was wrong with their methodology? Have you reviewed it??

jobby said: ... and exactly what was wrong with their methodology? Have you reviewed it??

jobby said: Then a not unreasonable expectation is that those who hold this position explain when and how which designer did what. Or least make an attempt. .... seems the cambrian explosion was a time of intervention also when the first cell appeared. a super intelligence beyond what we can comprehend fully. not human, not even close to human is the most likely. however there is a possibility that it also could have been on the level of humans but ahead of us time wise about 500 million years

For the uninitiatied, Yobbo has a tendency to suggest space aliens are responsible for evolution, but lacks the cajones to fill in the details.

Entia non sunt multiplicanda praeter necessitatem. (Entities must not be multiplied beyond necessity.)
Essentia non sunt multiplicanda praeter necessitudinem. (Don't use more postulates than you have to.)
Pluralitas non ponenda est sine necessitate. (Multiplicity is not to be asserted when it is unnecessary.)

Occam's Razor, William Of Occam (C.1285-1349)

It is precisely because ID postulates an entity called "the designer" that Occam is violated. You must prove that this entity is necessary.

However, IF the variance was reduced significantly by genetic drift as an artifact of the size of the studied populations, then Takahashi’s paper has NOT demonstrated that peahens do not prefer males with more elaborate trains.

They have not ruled out this possibility,

Therefore FL is foolish to suggest that their conclusions should replace the common wisdom. His suggestion is, in fact, anti-scientific.

FL said: Welcome Mr. Wisker. I discussed your essay because one of the evolutionists brought it up. I see that qualifier, "IF", is still being employed in key places.

However, IF the variance was reduced significantly by genetic drift as an artifact of the size of the studied populations, then Takahashi’s paper has NOT demonstrated that peahens do not prefer males with more elaborate trains.

But that's all we have for now. "IF." I imagine some evolutionists are very heavily hoping that the "IF" will get confirmed somehow. But for now, it's just an "IF." And nothing more. Takahashi's paper remains NOT overturned at this time.

They have not ruled out this possibility,

Nor have they or anyone else confirmed it at all. At this time, the "possibility" is nothing more than "a possibility."

Therefore FL is foolish to suggest that their conclusions should replace the common wisdom. His suggestion is, in fact, anti-scientific.

Hardly "foolish", and even more hardly "anti-scientific." Sure there are evolutionists who want to believe in "the common wisdom" no matter what, but the fact is that you now have on the table a strong (not perfect, but quite strong, with an advantage even you admitted to vis-a-vis previous studies) science-journal-published challenge to the "conventional wisdom." It won't go away. You'd like to see Takahashi's conclusion overturned, and I'm sure you're not alone, but for now all you can do is offer a few, very visibly qualified, potential criticisms---"IF" those potential criticisms happen to pan out in the future. Maybe they will pan out someday; maybe they won't pan out someday. Me, I'll just make a note of your blog essay and stay tuned to see what happens. But until such time as Takahashi et al is overturned, "IF" that happens, it's quite reasonable, rational, and in line with science to go ahead and suggest that yes the old stale preachings of peacock-feathers-are-evidence-of-evolution-via-sexual-selection, are incorrect. Hence it's okay to suggest that it's time to revise those textbooks and evolution websites to at least reflect the Takahashi challenge. FL

Fl,

While I appreciate your interest in my article, I can see a familiar pattern emerging in your responses. You cling to my careful use of the word 'if' like a drowning man grasping at anything to stay afloat. Let's consider the facts. First, Takahashi et al's paper is the only one of four major studies that failed to find female preference (there is also an Indian study,done on a completely wild population, which also found significant female preference for elaborate trains). Of all of them, the population studied by the Japanese researchers had the lowest variation in tail morphology. Although I did say their work had the advantage of a larger population and was conducted over a longer period of time (something the DI crowed overas well), it should be very clear that this advantage can be completely negated if the population does not have enough variation to detect selection in the first place. In fact, the longer the study is conducted, the less variation it can be expected to have, considering the small initial size and isolation of the population they were examining. Second, some of their criticisms of the other studies were off the mark,as I showed regarding the hours when observations regarding mating behavior were made. Third, they used a different methodology in determining male reproductive success, which also takes the teeth out of many of the advantages they claimed for their work over the others. So, given these facts, I think it is premature to accord their results the stature of a general statement regarding sexual selection in these birds, especially since three other, independent studies contradict their findings.

One thing I do find interesting about the Japanese paper is how the big bad Darwinist orthodoxy allowed its publication in the first place. I guess teh Darwinist police were asleep at the switch.

Dave WIsker said: Fl, While I appreciate your interest in my article, I can see a familiar pattern emerging in your responses. You cling to my careful use of the word 'if' like a drowning man grasping at anything to stay afloat. Let's consider the facts. First, Takahashi et al's paper is the only one of four major studies that failed to find female preference (there is also an Indian study,done on a completely wild population, which also found significant female preference for elaborate trains). Of all of them, the population studied by the Japanese researchers had the lowest variation in tail morphology. Although I did say their work had the advantage of a larger population and was conducted over a longer period of time (something the DI crowed overas well), it should be very clear that this advantage can be completely negated if the population does not have enough variation to detect selection in the first place. In fact, the longer the study is conducted, the less variation it can be expected to have, considering the small initial size and isolation of the population they were examining. Second, some of their criticisms of the other studies were off the mark,as I showed regarding the hours when observations regarding mating behavior were made. Third, they used a different methodology in determining male reproductive success, which also takes the teeth out of many of the advantages they claimed for their work over the others. So, given these facts, I think it is premature to accord their results the stature of a general statement regarding sexual selection in these birds, especially since three other, independent studies contradict their findings. One thing I do find interesting about the Japanese paper is how the big bad Darwinist orthodoxy allowed its publication in the first place. I guess teh Darwinist police were asleep at the switch.

You know FL is not going to understand or accept any of that, right? Yes, I agree that under ideal circumstances you should study a wild population in its own natural territory to know how a species is supposed to behave. So perhaps my earlier suggested experiment could be improved by a catch and release program of altered peacocks instead of taking a small population captive, which would result in altered peafowl behavior, unrelated to mating, that would damage the integrity of the study. And you need to have enough variation in a population to be noticable, hench my earler suggestion to cut off the peacocks’ trains, which you can refine to only remove half the trains or one quarter of the trains in further experiments

This picture just hit me why the peacock's tail has the "eyes". If you look at how transparent the rest of the tail looks you can see the purpose of the "eyes" They allow a great display of color and movement while the rest of the feather minimizes the aerodynamic cost of having such a large and conspicuous display device. As my husband always says." Ain't the designer wonderful?" Tongue firmly in cheek.

Mary Hunter said: This picture just hit me why the peacock's tail has the "eyes". If you look at how transparent the rest of the tail looks you can see the purpose of the "eyes" They allow a great display of color and movement while the rest of the feather minimizes the aerodynamic cost of having such a large and conspicuous display device. As my husband always says." Ain't the designer wonderful?" Tongue firmly in cheek.

Reading back through the entries a number of things have come to mind about why the male of so many species supports the burden of flashy display devices. A male with a large tail tells a female a number of things important to the survival of the offspring. A large tailed male is probably older therefore smarter, stronger or more lucky than the rest. He is also more parasite resistant as studies (sorry I can't name them) have shown that males debilitated by large infestations of parasites have less colorful displays and attract fewer matings. This is actually evolution at its most obvious the quest we need to answer is not why the devices but why those devices. Take a look at the Argus Pheasant with his exaggerated wing feathers. If these don't win him extra matings then they would rapidly revert to the shorter length more useful in an explosive get away.

Mary Hunter said: the quest we need to answer is not why the devices but why those devices.

starting a self-reinforcing chain reaction.

You know FL is not going to understand or accept any of that, right?

I can see a familiar pattern emerging in your responses. You cling to my careful use of the word ‘if’ like a drowning man grasping at anything to stay afloat...

Takahashi points out that grown of the peacock's train is dependent on the absence of oestrogen rather than the presence of testosterone. She says this undermines the assumption that the train is a sexual signal. "Until now, who cared that the peacock's train was under oestrogen control? Takahashi says. "We hope our paper will encourage others with (negative) data to publish." ----New Scientist Online, "Have peacock tails lost their sexual allure?" March 27 2008.

For example, Takahashi et al. found that a behavior known as “shivering” be important. It looks like a fertile field for further investigation.

"Since male peacocks appear to shiver in response to female run-arounds, the scientists think that male mating calls, which consist of multiple notes and sound very different than the noises females make, could affect mating success. The trains, on the other hand, may just be obsolete signals at this point, they suggest." Discovery.com News Online, March 26, 2008

"Traits under the control of estrogen are usually very poor indicators of phenotypic (visible physical attributes) and genotypic (DNA) condition," she (Louise Barrett) explained. "Accordingly, females are known to disregard estrogen-dependent male plumage cues when choosing mates." (same source) (Barrett, from the Univ. of Lethbridge, is one of the executive editors of the science journal Animal Behavior)

(Takahashi's study) throws a wrench in the long-held belief that male peacock feathers evolved in response to female mate choice. ----from Dale's Discovery News link

(Takahashi's study) illustrates that the story is more interesting and complex than we thought. One should never be too complacent and think that a problem has been solved." --- Louise Barrett

I think it is premature to accord their results the stature of a general statement regarding sexual selection in these birds, especially since three other, independent studies contradict their findings.

Takahashi)’s conclusion is effectively “We do not know the origin or original function of the peacock’s tail, but we think it originated a long time ago.” --- David Tyler

Yeast cells oc­cur in two dif­fer­ent mat­ing types, some­what akin to male and fema­le. Each type sig­nals to po­ten­tial part­ners of the oth­er type by pro­duc­ing an at­trac­tive chem­i­cal, called a pher­o­mone. But cells vary widely in how strongly they can sig­nal; the dif­fer­ences are ge­net­ic. Rog­ers and Greig en­gi­neered one of the “sex­es” of yeast cells, called MAT-alpha, to have ei­ther very high or very low sig­naling strength. They then mixed both types of cells with those of the op­po­site “sex” group, called MATa. This mix­ing was done in two dif­fer­ent ways: in one, the MAT-alpha cells were few, and so faced lit­tle com­pe­ti­tion among each oth­er; in the oth­er, they were many, so that they faced tough com­pe­ti­tion for mat­ing op­por­tun­i­ties. Only un­der the high-com­pe­ti­tion situa­t­ion, the strong-sig­nalling gene var­i­ant spread quickly through the popula­t­ion at the ex­pense of the weak-sig­nalling var­i­ant, Rog­ers and Greig found. This matched the pre­dic­tions of sex­u­al se­lec­tion the­o­ry, they added. “We have tested the sim­plest pos­si­ble sex­u­al se­lec­tion sce­na­rio,” they wrote. “Ob­serv­ing the real time ev­o­lu­tion of nov­el sex­u­ally se­lected traits, and pref­er­ences for them, is the ul­ti­mate test for sex­u­al se­lec­tion the­o­ry.” www.world-science.net/exclusives/081013_selection.htm

http://tinyurl.com/2kxyc7

You know FL is not going to understand or accept any of that, right?

Ummmm, Dale, I'm NOT the one who found himself apologizing to Mr. Wisker for a *previous* (and entirely avoidable) misunderstanding in this thread....Let's all work on our own understandings, yes? At any rate, let's continue a bit further.

Finally, of course, the disagreements have already started. The guardians of the "conventional wisdom" know they better say something on this one. Hence Petrie has already "dismissed" the Takahashi study, and Loyau likewise throws in her criticisms too, in the New Scientist article. And of course Mr. Wisker, you have your potential criticisms too---all iffy and unconfirmed as of now, but specific and worth noting in case confirmation should arise. Meanwhile, it's time to revise those textbooks and "Understanding Evolution" websites. Can't just keep on preachin' the same o' same o' as if Takahashi ain't on the table. The competitor is in the ring and she's a swingin' hard. FL

Overturned? Not yet.

It’s always “one swallow does a summer make” with the creo-bozos. Look, it’s just possible that the highly evolved peacock’s train has reached the end of its evolutionary rope, and is no longer sexually selected.

ignore that last paragraph. I forgot to delete it.

One more thing. I mentioned the 'shivering' behavior because it is an interesting part of the male behavior on the lek, and we don't know how much it contributes to the overall 'signal' to the female. However, as behavior it has been known and observed for a long time.

Dave Wisker said: ...Takahashi et al's results can be explained as the result of standard evolutionary forces in their particular population. That's a far cry from 'falsifying' sexual selection in peafowl, as the DI so desparately wants us and readers like FL to think.

To expand on Eric's point a bit, what ID and creationism in general lacks, is positive evidence in favor of their position. Their entire case, such as it is, rests on poking holes in evolution.

Imagine a murder. Negative evidence in favor of the ex-wife-diddit hypothesis would be the butler having an alibi (to make the analogy more apt it should be a remarkably flimsy alibi.) Positive evidence for the ex-wife-diddit hypothesis would be her fingerprints on the murder weapon. It is this kind of positive evidence that is completely lacking from cdesignproponentists side. Imagine being a prosecutor trying to convict the ex wife with a case that amounted to nothing more than "we can't figure out who else could have done it."

tresmal said: Imagine a murder. Negative evidence in favor of the ex-wife-diddit hypothesis would be the butler having an alibi (to make the analogy more apt it should be a remarkably flimsy alibi.) Positive evidence for the ex-wife-diddit hypothesis would be her fingerprints on the murder weapon. It is this kind of positive evidence that is completely lacking from cdesignproponentists side. Imagine being a prosecutor trying to convict the ex wife with a case that amounted to nothing more than "we can't figure out who else could have done it."

There is a larger point here, which is that FL is arguing the false dichotomy.

Stanton said: ...And the only reason why the prosecution insists that the butler be sent to the Gas Chamber is that "the butler always did it."

Try to realize that this line of argument, even if successful, never rationally leads to science’s accepting a hypothesis that has no evidence whatsoever behind it.

... I think the point is that both ID and Darwinism theories have points that dispute them and points that support them. To say Darwinism is a fact is simply not being objective or scientific.

Cobby said: Try to realize that this line of argument, even if successful, never rationally leads to science’s accepting a hypothesis that has no evidence whatsoever behind it. ... I think the point is that both ID and Darwinism theories have points that dispute them and points that support them. To say Darwinism is a fact is simply not being objective or scientific.

Darwinism is a fact in the sense that the aspects of it have been observed: inheritance, variation and natural selection

... well of course many aspects of Darwinism have been proven. But all of the subtheories must have substantial validation which they do not.

Of course NS happens but is it responsible for causing complex structures to evolve from simple ones? If that cannot be validated the whole theory is just another guess.

Cobby said: Darwinism is a fact in the sense that the aspects of it have been observed: inheritance, variation and natural selection ... well of course many aspects of Darwinism have been proven. But all of the subtheories must have substantial validation which they do not. Of course NS happens but is it responsible for causing complex structures to evolve from simple ones? If that cannot be validated the whole theory is just another guess.

Cobby said: ... I think the point is that both ID and Darwinism theories have points that dispute them and points that support them. To say Darwinism is a fact is simply not being objective or scientific.

tresmal said:

Cobby said: ... I think the point is that both ID and Darwinism theories have points that dispute them and points that support them. To say Darwinism is a fact is simply not being objective or scientific.

Hi jobby. You are wrong. ID does not have anything that supports it. And the only point against evolution is that there is more to learn.
Are you a raelian?

PvM said: ... I think the point is that both ID and Darwinism theories have points that dispute them and points that support them. To say Darwinism is a fact is simply not being objective or scientific.

Oops, my mistake, the blockquote in my previous quote should be attributed to "Cobby," not PvM. My apologies.