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Re: sinraptor/maniraptor



 > 
 > So it's therapods, carnosaurs, sinraptors
 > or therapods, carnosaurs, maniraptors?

Theropods (carnivorous dinosaurs) consist of ceratosaurs, carnosaurs, 
and maniraptors (at least to a first aproximation - there are some
types that do not quite fit in these three).

The carnosaurs include several groups: the allosaurs, the
torvosaurs or megalosaurs, the sinraptors, and maybe others.

 > (Perhaps instead of requesting books for my son, I should ask for some 
 > for myself ;^))
 > 
 > Finally, last week I asked about name changes (and received several 
 > examples)--here's another one Gorgosaurus is now Albertasaurus? 

There is still some controversy about this one.  Some years ago
somebody (I forget who) published a study that seemed to show
that most species originally assigned to Gorgosaurus (including
the type species) fell within the range of variation of the genus
Albertosaurus.  The same study also assigned some of the species
formerly in Gorgosaurus to a new genus, Daspletosaurus.  Later,
one species, G. lancensis, was shown to be unique, and placed
in another new genus, Nanotyrannus.

However, some recent phylogenetic analyses suggest that if
Albertosaurus is so constituted it is paraphyletic (that is
it has a single common ancestor, but excludes some of the more
derived descendents of that ancestor). Some taxonomists do not
accept paraphyletic taxa, and thus want to split Albertosaurus
back up again.  Other taxonomists accept paraphyletic taxa and
see no need to split Albertosaurus into "pure" lineages.  [Also,
the phylogenetic analyses that show Albertosaurus in the broad
sense to be paraphyletic need to be checked and double-checked
before they are solidly established].

swf@elsegundoca.ncr.com         sarima@netcom.com

The peace of God be with you.