[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

[no subject]

 96-02-11 17:47:37 EST, Robert.J.Meyerson@uwrf.edu (Rob
Meyerson) writes:

>Do you suggest that there are two lineages of theropods: the line including=
> _Allosaurus_, and another including _Dienonychus_?  I may be completely=
> missing the point, but it seems that Archy's line is being taken out of
> theropods proper by the above statement.

It all depends on what you mean by a lineage. The _Allosaurus_ lineage and
_Deinonychus_ lineages diverged at different times from from the lineage
joining the common ancestor of the dinosaurs to birds: _Allosaurus_ earlier,
_Deinonychus_ somewhat later, which is why _Deinonychus_ was more "birdlike"
than _Allosaurus_. The lineage leading to _Archaeopteryx_ diverged later
still, and so _Archaeopteryx_ was even more "birdlike" (particularly in skull
anatomy) than _Deinonychus_.