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Re: Terrestriality is a bias
In a message dated 6/9/00 5:00:12 PM EST, dannj@alphalink.com.au writes:
<< Oops - should have said "non-avian" theropod. Anyway, in my opinion
flying into trees is cheating. Where's the challenge? The threat of
imminent death at a fatal plunge? In the absence of the latter, climbing
skills don't need to be quite as sharp as in non-flying arboreals. Then
again, I am a primate, so I'm probably biased. :) >>
Arboreal doesn't necessarily mean climbing, just dwelling in trees. According
to BCF, avian flight is the ultimate solution to the sometimes precarious
problem of living in trees. The Falling Problem is the biggest single
challenge to a vertebrate that is making use of trees, and it can be
ameliorated by body modifications such as hollow bones, extra-sharp claws,
prehensile hands, feet, and tails, fuzzy dermal coverings, aerodynamic dermal
structures, big eyes and good hand-eye coordination--anything that will help
the animal lessen the damage from a fall or hold on to a tree better. Lots of
these features also occur in nonavian theropods, often simultaneously, which
is difficult to account for unless there was once an arboreal stage in their
evolution.