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Re: Thou Shalt Not Climb!



mariusromanus@aol.com writes:

So, what I'm wondering, is how did selection take place for pre-perching birds that were landing in trees with zero adaptations for such?

Many modern birds alight upon objects without having 'perching' feet. Gulls and pelicans can certainly perch *upon* things (but don't have much of a grip). I suspect that webbed bird feet in general are not very 'perchy' (depending on exactly how you define the verb 'perch' - I can perch upon a stool without using my feet to grip it :) ).


As far as early birds went, grasping feet could have been used first to grap prey, which later proved useful for perching upon branches. That's not to say that earlier non-grasping feet prevented birds from alighting on objects though - or that early volant predators necessarily used their raptorial feet to do a lot of tree perching either.

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Dann Pigdon
GIS / Archaeologist              geo cities.com/dannsdinosaurs
Melbourne, Australia             heretichides.soffiles.com
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