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FW: MSNBC article
Larry Febo wrote...
<Just read the Tom Holtz article concerning Bird Origins. Interesting
< summary, but I was disappointed not to see mention of opposing views
< stating Birds as ancestors to Dinos.
Sauropods and ornithischians are descended from birds?! This is a new one
Whether or not SOME Cretaceous theropods are secondarily flightless
descendants from _Archeopteryx_ or a closely related forms, birds would STILL
be descended from some kind of Jurassic theropod (perhaps a basal dromeosaur
lacking some the derived features suggesting to some that suggests the some
that Cretaceous forms are secondarily flightless); what else would they be
descended from? Psudosuchians? Crocodiles?
Even if you except Olshevsky's idea that ALL theropods are descended from
several radiations of arboreal forms, this still only covers the theropods; and
the "dino-birds" would still technically be dinosaurs (unless dinosaurs are
polyphyletic). "Birds Came First" is just a cute catch phrase for a theory
that suggests that early theropods were arboreal, and that ground dwelling
theropods are a polyphyletic group representing several radiations from
arboreal forms; at least _ONE_ of which already achieved flight. I'm sure
Olshevsky will chime in if I've misrepresented his ideas.
In any case, the paper is on BIRD origins, not necessarily "bird-like,
possibly secondarily flightless theropod" origins.