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Peacock feathers are supposed to produce colours by surface structures modulating the light (in addition to the usual absorption/reflection mechanism)... https://en.wikipedia.org/wiki/Structural_coloration

But how does that explain the existence of an albino peacock? https://www.favrify.com/wp-content/uploads/2015/02/peacock1.jpg

Does albino mutation change the physical structure of feathers in addition to the lack of colour pigments?

Does anyone have a close comparison of the physical difference of the albino vs coloured peacock feathers?

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    $\begingroup$ @Tytoalba I did search a fair bit on google and visited probably 7-8 websites, but found none which discuss the albino peacock's peculiarity. I am not a biologist, so I don't know the best places for such research (other than googling)... so I am not sure my rigor of research matches your expectation. $\endgroup$ – Jug Jun 13 '17 at 19:01
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    $\begingroup$ 'I am not a biologist'- me neither. :) It was just a pointer because Bio website often receives questions that show no prior research(the level is expected to be Google search mostly). Between you can always check Wikipedia, one can find almost anything on Wikipedia. Since it does have mistakes, it is always better to crosscheck. On googling 'White feathers of peacock', the peafowl link showed up, it mentions leucism at the end of Plumage paragraph. $\endgroup$ – Tyto alba Jun 13 '17 at 19:44
  • $\begingroup$ More specifically this site explains that the black pigment absorbs the incoming light, leaving the iridescence of the feather's fine structure to dominate. Albinos, which lack this light absorbing pigment have white feathers simply as a "reflection" of the white proteinacious content of the unpigmented eather webexhibits.org/causesofcolor/15C.html $\endgroup$ – PlaysDice Jun 23 '17 at 23:42
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The surface structuresa that are responsible for the structural coloration of peacock feathers are actually barbules and rods made of the very same biopolymer that is responsible for pigmentation in many other animal species, namely melanin. Just as in other animals, melanin is produced in the melanocyte cells which reside in the skin's epidermis. The conditions of albinism or leucism are due to mutations to genes responsible for melanin expression in those cells, or their absence. So although structural coloration is resposible for the colorful peacock feather, it is the same mechanism that leads to colorless feathers as in other animals.

Reference

a Zi, Jian, et al. "Coloration strategies in peacock feathers." Proceedings of the National Academy of Sciences 100.22 (2003): 12576-12578. https://dx.doi.org/10.1073/pnas.2133313100

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    $\begingroup$ Although melanin is a polymer of derivatives of tyrosine, and may contain cysteine, it is not a protein. But +1. $\endgroup$ – Alan Boyd Jun 13 '17 at 19:01

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