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Re: Screaming dromaeosaur biplane killers of the air
"Philidor" <email@example.com> wrote;
Are you sure that you want to include the 'use it or lose it' principle?
There goes retention of neutral mutations, among other problems.
Yes, I'm quite sure. I don't think one can assert that the hindlimb
feathers were 'neutral'; as Xu et al. (2003) note, enormous feathers
sprouting from the lower hindlimb would have been an impediment to running.
BTW, it is difficult to prove that _Archaeopteryx_'s legs were unfeathered.
What can be said is that the hindlimbs of _Archaeopteryx_ specimens lack the
pennaceous feathers preserved along its distal forelimb and tail. However,
the trunk and upper arm of _Archaeopteryx_ specimens lack feathers, and
their absence from these parts (and from the legs) may be a taphonomic
artifact. Or, it could be real. However, some neornithine birds from the
Messel lack humeral feathers, though more distal wing feathers are clearly
present. This is certainly an artifact.
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