Re: Madagascan Flying Raptor is INDEED a Madagascan Flying Raptor...

[Jeff Hecht <jeff@jeffhecht.com>]

Another interesting thing about this paper is that Pete Makovicky et al believe 
that Rahonavis represented a second evolution of flight. They don't even 
mention Greg Paul's flying common ancestor theory. Instead, they believe that 
it's relatively easy for this group to evolve long arms and develop flight. 

Assuming the relationships hold up, this discovery spotlights some big 
questions about the process of evolution, and how it's related to development. 
Research on evolutionary development ("evo-devo") shows that many traits arise 
from the effects of one gene regulating the activity of another. Thus one gene 
may switch  on and off the gene which actually controls growth of the limb. 

In any case, Buitreraptor is one odd-looking critter, which you can see on the 
cover of this week's Nature. The magazine's web site also opens to show a photo 
of a 'hobbit' skull with that of a modern human. I have a report in this week's 
New Scientist, but I think it's only in the print edition or in the premium 
second of the web site. 



At 3:09 PM -0400 10/12/05, Thomas R. Holtz, Jr. wrote:
[clipped]>
>Here's another cool thing. Rahonavis is not at the base of Unenlagiinae 
>(Buitreraptor falls there), but it did retain/reverted to
>the ancestral eumaniraptoran size. Microraptor is comparably-sized, and while 
>not as long armed as Rahonavis likely also had some
>aerial ability.  As do basal avialians.
>
>So the Greg Paul hypothesis of flying ancestors of birds and dromaeosaurids 
>gets some more support than before. And the possibility
>that Velociraptor, Dromaeosaurus, and Deinonychus are all secondarily 
>flightless is better than it was based on earlier evidence.
>
>Not to say there aren't complications: the short-armed troodontids, for 
>instance. But actually flying dromaeosaurids are looking a
>lot more likely...
>

-- 
Jeff Hecht, science & technology writer
jeff@jeffhecht.com
Boston Correspondent: New Scientist magazine
Contributing Editor: Laser Focus World
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