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Re: dinosaur behaviour: other aspects

HP Pickering quoted:
<It is useless to argue that natural selection would favor a
vertebrate with two wings in addition to its four
limbs, because no such variation in the genes
controlling early segmentation has occurred, or if it
has it has not been of a kind that would allow regular
development to proceed.>
This seems a bit of a just-so-story on the author's part.  After all, as he
says earlier:
<Evolution is not an unfolding but an
historically contingent wandering pathway through the
space of possibilities. Part of the historical
contingency arises because the physical conditions in
which life has evolved also have a contingent history,
but much of the uncertainty of evolution arises from
the existence of multiple possible pathways even when
external conditions are fixed.>
He can't say that a mutation of 4 legs and wings is not of a type that would
allow regular development to proceed unless he has direct genetic proof.
The fact that he can't see any now may only mean one of those contingencies