[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: RE: how small is small?
>whatever level you want to divide into size ranges). Thus a "small"
>sauropod might be larger than a "large" stegosaur.
A small sauropod is larger than a large almost anything else, except for
>By the way, wasn't the original "CARNOSAURIA" a grouping derived
>partly from size (ie "Carnosaurs = large theropods")?
No, no, no, no, no. Okay, yes, partly. Friedrich von Huene, who coined
Carnosauria and Coelurosauria, recognized that some large theropods were
closer to coelurosaurs than to Carnosauria (the latter including Allosaurus,
Megalosaurus, what are now Eustreptospondylus and Metriacanthosaurus, and a
few others). For example, Huene observed that tyrannosaurs (deinodonts back
then) were closer to ornithomimids than any other theropods known at the
time, and that Ceratosaurus was phyletically close to Coelophysis. Pretty
observant fellow, I must say!
> I'm sure that the
>definition is more technical and rigorous now :)
It is! Carnosauria = Allosaurus and all taxa sharing a more recent common
ancestor with Allosaurus than with birds. Incidentally, Allosaurus is the
ONLY genus which has always been in Carnosauria.
Thomas R. Holtz, Jr.
Dept. of Geology
University of Maryland
College Park, MD 20742