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Re: Phylogeny of Maniraptora

On Tue, Jun 03, 2003 at 03:11:20PM -0500, Tim Williams scripsit:
> James R. Cunningham <jrccea@bellsouth.net> wrote:
> >> >Did the "four-winged" stage precede two winged animals, or are the
> >> >"four-winged" theropods descended from theropods that sported only
> >> >pectoral wings?  There is probably no way of telling at this time.
> >
> >Why do we always use binary logic?  What's wrong with trinary?
> If you have another hypothesis, I'd love to hear it.

The hips that support a splayed stance strongly suggest an ancestrally
scansorial mode of life; they're morphologically very different from the
strongly front-to-back hips of the ancestor of modern birds.

Microraptor gui might well be the example of the trees-down mode of
evolving flight in theropods, and otherwise pretty much independent of
the main maniraptors->birds line of descent.

oak@uniserve.com | Uton we hycgan    hwaer we ham agen,
                 | ond thonne gedhencan    he we thider cumen.
                 |   -- The Seafarer, ll. 117-118.