RE: dinosaurs did eat grass

[Jeff Hecht <jeff@jeffhecht.com>]

At 5:37 PM -0500 11/17/05, Thomas R. Holtz, Jr. wrote:
>I haven't seen the paper itself yet (although maybe up online now), but the 
>brief reports in Nature's online news section and BBC's
>news site show a pretty convincing phytolith.
>
>Now if we can extend the grasses back to the Early Cretaceous (at least in 
>western Gondwana) we might FINALLY make sense of
>Nigersaurus and the rebbachisaurids in general: white rhino analogues...
>
Getting grass back to the early Cretaceous will be difficult. The authors model 
takes the origin of grasses back to about 100 million years ago, not quite far 
enough. Nonetheless, it's well worth going through herbivore coprolites looking 
for phytoliths; it might get you into Nature :-) 

If we assume the titanosaur was eating everything within its reach, grasses 
were only a small fraction of the foliage in a forest environment. The authors 
don't think it had any dental adaptations for feeding on grasses, but I don't 
think they have teeth. 

There are late Cretaceous mammals called gondwanatherians which do have teeth 
with thick enamel, and may have specialized in eating grasses. That might make 
sense for a prairie-dog sized critter, but I would doubt something the size of 
a dinosaur would specialize in eating a plant that was rare in its environment. 

Obviously a big question is what were those grasses? All they have is the 
phytoliths, which are definitely grassy but don't narrow down to specific 
modern grass groups. 
-- 
Jeff Hecht, science & technology writer
jeff@jeffhecht.com
Boston Correspondent: New Scientist magazine
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