Wednesday, January 02, 2008

Berberosaurus liassicus

Holiday's are over. I've got more to say, but for the moment, let me just comment in this recent discover in a Toarcian formation in the High Atlas mountains of Morocco---Berberosaurus liassicus---a basal abelisaur. This is pretty interesting, because otherwise we haven't found any early abelisaurs, and they were considered a Cretaceous radiation of theropods. Post-Ceratosaurus as it where, which was considered an ancestor. Although abelisaurs are still nested within ceratosaurs, clearly Ceratosaurus itself had to be a parallel development rather than an actual ancestor.

Funny; just a few years ago Ceratosaurus was considered the last hurrah of an earlier type of therapod. Now, with the abelisaurs, we realize that the big success of the family was yet to come. And we now don't believe that ceratosaurs are nested within coelophysids anymore either.

That's the funny thing with dinosaur studies. New discoveries can really throw your beliefs out of whack at a moment's notice. The somewhat recent discovery of grass going back almost 100 million years (instead of appearing sometime after the dinosaurs extinction as was previously believed) and dinosaur coprolites that contain grass is another one.

Anyway. More to come on the blog later. I won't tell you about my holiday, but I may spend a moment talking about Japanese 2-D fighting games and S. M. Sterling's brilliant (so far; I'm less than halfway through) novel The Sky People.

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