Literature

Darwinists have a reputation for advancing 'plausible scenarios'. These stories arise because there has to be a gradualist route for forming any biologically interesting structure. Peacock feathers are a case in point, purely because their strikingly beautiful displays cannot be overlooked or ignored. Since elaborate tail feathers do not make peacocks stronger or physically more fit, the mechanism of sexual selection is invoked. The Understanding Evolution for Teachers web resource has this to say on the subject:

"Sexual selection is a "special case" of natural selection. Sexual selection acts on an organism's ability to obtain (often by any means necessary!) or successfully copulate with a mate. Selection makes many organisms go to extreme lengths for sex: peacocks maintain elaborate tails [. . .] Sexual selection is often powerful enough to produce features that are harmful to the individual's survival. For example, extravagant and colorful tail feathers or fins are likely to attract predators as well as interested members of the opposite sex."
Source: go here.

"The sight of a feather in a peacock's tail, whenever I gaze at it, makes me sick!" (Charles Darwin, in a letter to botanist Asa Gray, April 3, 1860)

Unfortunately, for Darwinists, empirical research has failed to sustain this thesis. After spending years studying breeding birds, the researchers came to the conclusion that "peahens do not prefer peacocks with more elaborate trains".

"The feather train on male peacocks is among the most striking and beautiful physical attributes in nature, but it fails to excite, much less interest, females, according to new research. The determination throws a wrench in the long-held belief that male peacock feathers evolved in response to female mate choice. It could also indicate that certain other elaborate features in galliformes, a group that includes turkeys, chickens, grouse, quails and pheasants, as well as peacocks, are not necessarily linked to fitness and mating success."

The researchers have taken note of previous work and the various hypotheses that have been proposed. Their summary reveals that they have been thorough in following up every lead:

"To date, the peacock's train has been proposed not only as a target of current female choice (e.g. Petrie et al. 1991), but also as an indicator of good genes (Petrie 1994). However, there may be at least four problems with these hypotheses.
First, male train morphology seems not to be the universal cue of choice because there is evidence both for and against the effect of male train morphology on male mating success. [. . .] Second, the ways in which females assess male trains (unless females have the ability to count eyespots per se) have been questioned repeatedly but have not been fully investigated. Third, there is no consensus on which traits characterize males with the most elaborate trains. [. . .] Fourth, to our knowledge, mate choice based on a male plumage ornament that is under oestrogen control is very rare."

Their 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':

"We propose that the peacock's train is an obsolete signal for which female preference has already been lost or weakened, but which has none the less been maintained up to the present because it is required as a threshold cue to achieve stimulatory levels in females before mating and/or it is maintained as an unreliable cue [. . .]."

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.

Peahens do not prefer peacocks with more elaborate trains
Mariko Takahashi, Hiroyuki Arita, Mariko Hiraiwa-Hasegawa and Toshikazu Hasegawa
Animal Behaviour, 75(4), April 2008, 1209-1219 | doi:10.1016/j.anbehav.2007.10.004

Abstract: The elaborate train of male Indian peafowl, Pavo cristatus, is thought to have evolved in response to female mate choice and may be an indicator of good genes. The aim of this study was to investigate the role of the male train in mate choice using male- and female-centred observations in a feral population of Indian peafowl in Japan over 7 years. We found no evidence that peahens expressed any preference for peacocks with more elaborate trains (i.e. trains having more ocelli, a more symmetrical arrangement or a greater length), similar to other studies of galliforms showing that females disregard male plumage. Combined with previous results, our findings indicate that the peacock's train (1) is not the universal target of female choice, (2) shows small variance among males across populations and (3) based on current physiological knowledge, does not appear to reliably reflect the male condition. We also found that some behavioural characteristics of peacocks during displays were largely affected by female behaviours and were spuriously correlated with male mating success. Although the male train and its direct display towards females seem necessary for successful reproduction, we conclude that peahens in this population are likely to exercise active choice based on cues other than the peacock's train.

See also:

Viegas, J., Female Peacocks Not Impressed by Male Feathers, Discovery News, March 26, 2008

Wiker, B. The Peacock Principle: Beauty, God, and Darwinism, The Discovery Institute, August 2006