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Re: [davis@kahaku.go.jp: Q's arising from Archaeopteryx feathers]



In a message dated 96-10-01 14:54:25 EDT, znc14@ttacs1.ttu.edu (Jonathan R.
Wagner) writes:

>        A well argued hypothesis explaining how feathers developed for
> flight before they developed for insulation has yet to cross my desk.  This
> is why people think that them contour feathers *may* (and this is your area,
> not mine, so feel free to slam) not have preserved. 

There is >no< "well-argued hypothesis" explaining how feathers developed,
period, just a lot of Just So Stories, BCF included (by the way). The
development of feathers for insulation requires a need for insulation, which
has never been established in avian ancestors because we know too little
about their energy budgets. All arboreal animals, however, >do< face the
Falling Problem, which a number of adaptations, including aerodynamic
feathers of various kinds in various places on the body, can alleviate. The
case for feathers arising as a solution to the Falling Problem is presently
just as good as the case for feathers arising as insulation.