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Re: All this flying talk---then comes the why..or something
In a message dated 98-04-13 03:08:32 EDT, email@example.com writes:
<< Maybe avian flight did not avolve to escape danger - but to be the one that
makes it! >>
BCF asserts that the arboreal lifestyle, though not specifically flight, in
archosaurs was likely but not certainly a response to predation: small
archosaurs found refuge from larger predators in the trees and perhaps in
other high places, such as cliffs.
BCF asserts that ornithopting is the >ultimate< solution to the falling
problem: once an animal establishes itself in an arboreal or acronomic
lifestyle, evolution will select for features that help it to survive falls.
Among such features are large, curved claws; prehensile tails; grasping fore
and hind limbs; skeletal lightening (via hollow or pneumatic bones); skeleton
braced for shock absorption; excellent eyesight, coordination, and balance;
and aerodynamically reactive dermal structures. Prehensile tails are well
known in the probable ornithodiran _Megalancosaurus_ and its relatives, but do
not occur (as far as I know) in theropods. All the other features do occur in
theropods to a greater or lesser extent--depending on the theropods.