Re: Re: Segnosaurs (again)

[Thomas_R_HOLTZ@umail.umd.edu (th81)]

>> Surely it is the number of termites ingested rather than the size of each
>> individual termite that matters!  Anyway, if segnosaurs were termite-eaters
>> their hyoid apparatus (is it known?) might show evidence of an elongate
>>tongue.
>
>I guess I was being a bit flippant when I made that comment.  A good
>therizinosaurid skull would help resolve the issue of their eating
>habits.  Which brings me back to a previous question - is any skull
>material known for _Therizinosaurus_ or _Alxasaurus_?

The former's skull is unknown, only the dentary is known of _Alxasaurus_.
Of course, _Erlicosaurus_'s skull is the best preserved of any Mesozoic
theropod!!  The teeth of _Erlicosaurus_ are "troodontiform" (pinched based
and big denticles), which are morphometrically distinct from serration
densities associated with vertebrate hypercarnivores (some sharks, basal
synapsids, sabrecats of all stripes, varanoid lizards, pseudosuchians
(including rauisuchids and xiphodont crocs), and most theropods).  This may
indicate a non-hypercarnivorous diet (i.e., a diet which includes things
other than vertebrate flesh, such as arthropods, molluscs, fungi, plants,
etc.)

>I don't know if mound-building termites existed in the Mesozoic (are
>there any palaeoentomologists out there? :-)).  In my opinion, ant-
>eating therizinosaurids are certainly feasible.  But I like the
>chalicothere analogy better - that therizinosaurids used their claws
>to hook branches down to within reach of the mouth.

As did ground sloths...

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661