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Re: Brooding (was Re: Arms into wings)



In a message dated 3/5/99 1:31:04 PM, Tom Holtz writes:

<< Gentlemen, gentlemen, gentleman.
Might I suggest that you actually employ the appropriate test for this?
That is, map this trait on a bird phylogeny (or multiple bird phylogenies)
and find out its distribution? That way you can find out if it is basal for
Neornithes, at least. >>

Thanks, I needed that . . . .

Actually, what you suggest is what Mark and I did for our Dinofest 98 paper,
complete with dendrogram. We're just looking for more data points with which
to decorate the tree. You're right, Neornithes are covered, in spades. What is
lacking in your example is some input regarding wing-feather sheltering of
hatched offpsring. That is what makes us interested in pushing back the date
of first known (or reasonably extrapolated) instance of chick covering. Hence
the search for more examples, to strengthen the "archaeopteryx probably wing-
covered its chicks" basal brooding concept, which supports our "maybe archae's
non-flying ancestor did as well" argument by getting close on the geological
time scale. We plan to dig up the archae-sheltering-its-hatchlings-with-wing-
feather-impressions fossil at a later date.
Thomas P. Hopp, Ph.D.