[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Avian origins: new analysis confirms ancient beginnings
On Feb 6, 2008 8:31 AM, Stephen V. Cole <email@example.com> wrote:
> Huh? Ok, I'm an engineer not a paleontologist, but even I know birds
> go back to archy in 154mya.
They're talking about "modern birds", i.e., the avian *crown group*
(sometimes called _Neornithes_, although others of use prefer to use
the name _Aves_ in a strict sense for this group). _Archaeopteryx_ is
well outside the crown group.
As Tim Williams mentioned, though, _Vegavis_ is an anseriform from the
Maastrichtian, so the fossil record already tells us that avians
(i.e., crown group avians) had diverged in to *at least* five lineages
(pan-Palaeognathae, pan-Galliformes, pan-Anhimidae, pan-Anseres, and
pan-Neoaves) by the end of the Mesozoic. I haven't read the paper yet,
so I don't know where they got the 60 Mya figure from.
T. Michael Keesey
Director of Technology
2894 Rowena Avenue Ste. B
Los Angeles, California 90039