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Re: comments in this week's Science about the Thermopolis Archaeopteryx



Tom Holtz (tholtz@geol.umd.edu) wrote (quoting the _Science_ note):

<"Mayr & Peters explictly support elements of Greg Paul's Secondary
Flightlessness hypothesis: "Corfe and Butler incorrectly state that we
suggested "birds, or avian flight, originated twice." We do not assume that
flight was gained independently more than once within theropods but consider it
more likely that flight ability was lost several times independently in the
clade including Archaeopteryx, deinonychosaurs, and pygostylians (7). This is a
reasonable assumption irrespective of the position of Archaeopteryx, because
the presence of modern-type wing feathers in the dromaeosaur Microraptor (8)
alone suggests secondary loss of flight ability in the larger species of
Deinonychosauria.".>

  This is assuming 1) *Microraptor* flew, powered or not, 2) and that
*Microraptor* is along the lineage toward other deinonychosaurs and thus
represents the plesiomorphic condition for those other lineages (so far, its
morphology seems isolated to Microraptoria).

Jaime A. Headden
http://bitestuff.blogspot.com/

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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