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Re: Meet Protopteryx: two Yixian maniraptorans in one week!



Eric,

(i) elongation of scales

(snip)

Isn't it funny that in the recent "refutation" of Longisumata (sic) that
what's described in (i) above was laughed off has having nothing whatsoever to do with the evolution of feathers!<<<


And it should be laughed off this time. On purely developmental grounds it would be almost impossible. While simple perforations are obviously possible through variation in low-level genetics (e.g. fenestration), highly repetative structures are the result of duplicated controller genes, after which selection on heterochronistic variation provides the refined struture. Proximally branched dinofuzz (if Currie's description holds up to SEM or other fine morphological analysis) would be the ideal forunner to the genetic evolution of avian feathers.

Scott
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