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Re: Velociraptor footprints



>> Don't cats do this, more or less?
>Yes, as you said, more or less.Cat's feet are a little different than
>Velociraptor's though and you don't have entire toes held up.

The feet of cats have rather extreme morphological adaptations that allow
for >all< of the toes to retract. In addition, cat toes are very short,
unlike the very long, slender toes of dromaeosaurs and troodontids.

 But I do
>think it almost mandatory that some dromaeosaurids carry their digit 2
>this way.Those claws are proportionately enormous and very sharply
>curved.The thought of them constantly in contact with the ground seems
>ludicrous to me.

Extant ratites, that have been known to kill even humans with their inner
digit's claw, do fine without carrying their second digit off the ground. 

It isn't exactly hard to imagine them lifted either.Even
>in Tyrannosaurus the two "outer" toes are larger and stronger, and,
>correct me please if I'm wrong, were the principal weight bearers.

But this is a >cursorial< adaptation, for speed.  

[snip]

---And just to think about....Struthio camelus is
>very didactyl,very cursorial, and gets along just fine.I can't see how
>giving an Ostrich a raised inner digit would affect it's impressive
>ground covering abilities in the least---Speculation as usual, Sean C.

Wouldn't the constant hyperextension of the second digit cause a decrease in
the performance of the rest of the locomotory musculature of the hind limbs? 

This is all good speculation, but until even ONE shred of physical evidence
exists, I will remain unconvinced. Of the tens of thousands (hundreds of
thousands?) of small theropod tracks that have been documented, NOT EVEN ONE
unambiguously shows a retracted second digit. Period. Occam's Razor tells us
that small theropods simply didn't carry their second digits off the ground.

Sam