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Matthew - thanks tons for the info! I think I was up to speed with the
fliers, but some of the others were a real revelation! As you might expect
of me, I had been thinking of creating a tree based on one characteristic
and time of appearance (as a flexible guide) - crazy, eh? Now so many of
the "protobirds" seem to have had hooked ribs to some extent that far from
being a rather confusing pattern, it looks pretty clear cut from my point of
view (so long as we ignore the stegosaur): starts at the start of the Cr
(sorry - K!) and pretty well includes all the usual suspects except enant.
birds, troodonts and ornithomimids. Those last two have their origins very
early in the K I believe. Of course some of the protobirds have such
powerful arms (most extreme example - oviraptor?) for whatever bizarre uses
they put them to, they _may_ have grown their own instead of inheriting
them, though I doubt it.
The Moa in the NHM looks as though its uncinates have been glued on as an
afterthought, but all the dead birds I've found seem to have them as solid
outgrowths of the ribs. (It'll be chicken for dinner tomorrow.) When you
say oviraptorids always have prong-like processes around the ribs, does this
mean lying around having fallen off? That would look like an inherited
feature to me - if it's anything like the Moa.
Funny about Tyrannosaurs though. They seem to have been quite "advanced",
and successful of course, and appeared latish. Could they have lost theirs?
Original Message was from: Matthew Troutman <email@example.com>
Date: 22 February 1998 04:51
Subject: Re: Cladistics (was Sci. Am. - present)
John V Jackson firstname.lastname@example.org
Ruminants ruminate . . . uncinants uncinate