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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.