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Re: New(ish) paper II



Mickey Mortimer wrote:

"The pelvic connections to the hind limbs [in Microraptor gui] seem
irreversibly adapted to a gliding niche, and not conducive to running or to
flapping flight."

The authors believe that _Microraptor_ spent ALL its time in trees. So if it landed on the ground, it was by accident. Makes one wonder what happened when _Microraptor_ did hit the ground. Did it scream for help? "Put me back in my tree!" yelped little _Microraptor_. "I am not bipedal any more!"


Oh good!  Someone's finally studied the femoral head and acetabulum to
determine their range of motion. ;-)

Yes: Ha ha.

(On a serious note, I'm not sure the 'squished' preservation of _Microraptor_ would allow this type of study. Then again, I'd be very happy to be proved wrong.)

At last, the tripedal putative 'protobirds' can be discounted as avian ancestors.

Yep, and there goes my pet hypothesis that birds evolved from worms. Darn!

The "Czerkas Rule of Evolutionary Constraint" makes a couple appearances.
And look- more functional information for Microraptor gui.  Apparently it
couldn't stand bipedally, who would have thought?

Maybe it stood one leg and pirouetted fom place to place.

Aha! So that's why we find no direct ancestors in the fossil record- they
all lived in habitats unfavorable for preservation. Every time a speciation
event would be near, the population would retreat to the mountains until
they developed autapomorphies.

It's worked for BCF.

Now I see....
Their phylogenetic hypothesis seems very confused, reminding one of Feduccia
(2002). I _think_ Long et al. are MANIACs. They state birds evolved from
Longisquama relatives, but also that Eumaniraptora including dromaeosaurs,
troodontids and birds is a strong hypothesis. Coelurosaurs are the sister
clade of birds, much as in Czerkas' work. Who knows where other dinosaurs
go, of course. Then again, sometimes Microraptor gui is referred to as a
dromaeosaur only in quotes. And they talk about feathered dinosaurs,
without saying they are actually or may be birds instead. Confusing...

You're thinking to much. It is the authors that are thoroughly confused. Peter Makovicky says one thing, Alan Feduccia says another... What is one to do except try and accommodate two mutually incompatible theories?



Tim

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