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Re: the reason I asked about maniraptor limbs



Tim Williams writes:

I thought this was true for all maniraptorans. The palms face inwards, but the hindlimbs are held vertically and restricted to parasagittal movement. Whether this combination is suitable for trunk-climbing is a totally different question.

This is pretty much how cats scale a vertical trunk. Foreclaws grip the sides of the trunk, while hindclaws mostly face forward to provide traction. Other (more arborial) species that can rotate their ankles to grip side-to-side are capable of decending a trunk head-first, since their fore and hind feet can swap roles. Cats can't do this, and have to back down a vertical trunk slowly (or wait for the fire department).


There's a simple way to demonstrate this up close. Put a cranky cat on its back and try to tickle its belly. Your hand will be gripped mercilessly from side-to-side by the manual claws (causing puncture wounds), while the pedal claws will pump back and forth in a more saggital plane (causing lacerations). Try it and see...

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Dann Pigdon
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://heretichides.soffiles.com
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