I found a reference (Source) to the genetics involved with how the feather evolved.
However, some of the information in the extract has since been shown to be inaccurate, so I took the liberty of correcting some of the statements.
The "Sinosauropteryx" which McConnell refers to turned out to be degraded collagen fibres
See(Proc Biol Sci. Aug 7, 2007)
A new Chinese specimen indicates that ‘protofeathers’ in the Early Cretaceous theropod dinosaur Sinosauropteryx are degraded collagen fibresThis is still being repeated in a publication dated 2013. (?)
(http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2270928/)
"...we investigate feather novelty and homology by comparing transcriptomes from different stages of developing feathers, different scales, and claws.
Transcriptomes were assayed at different developmental stages and in multiple species, including two distantly related birds, Chicken (Gallus gallus) and Emu (Dromaius novaehollandiae), and American Alligator (Alligator mississipiensis). We found that in early development feathers and scutate scales, an asymmetric avian scale, share similar gene expression compared to other scales and claws. However, as development progresses gene expression in feathers becomes distinct, suggesting later stages of feather development are novel. This close relationship between feathers and scutate scales in early development, and subsequent unique expression in later feather development is supported independently by transcriptomes from both epidermis and dermis, as well as across multiple avian species."
(Source)
Amazon Alibris Barnes and Noble |
A genetic explanation for the evolution of the feather; the modification of the reptilian scale.
Homology, Genes, and Evolutionary Innovation By Günter P. Wagner
Princeton University Press, Apr 13, 2014 - Science - 496 pages
(Source)
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