Re: Deinocheirus (was Sauropodz r kewl WAS: silly conversation on 2012 US presidential race)

[Tim Williams <tijawi@gmail.com>]

Anthony Docimo <keenir@hotmail.com>:

> Therizinosaur forelimbs were heavily muscled, right?  Maybe its not so much a 
>matter of "pull food to mouth" as a matter of "pull branch down enough
>  that tender leaves are in reach of mouth".


That's certainly a possibility.  The forelimbs (including the hand and
wrist) certainly do appear to have been built for strength.  However,
therizinosaurs show a trend of *decreased* grasping abilities by the
manus.  The manual phalanges became shorter; collateral ligament pits
were reduced (or lost altogether); and the dorsal lip on the unguals
was lost.


So the hands might have been used to grab thick boughs and branches -
possibly using both hands at once - and pulling the tips toward the
mouth.  But the long-clawed hands of _Therizinosaurus_ seem to be
ill-equipped for this particular purpose; but as it represents an
extreme example, its lifestyle might have been a little different to
other therizinosaurs.








Cheers

Tim