RE: _Microraptor zhaoianus_

[Jeff Hecht <jhecht@world.std.com>]

Tom Holtz wrote
> *The metatarsal I and pedal digit I are very distally placed, and the
> penultimate phalanx of each of the toes is elongate: Xu et al. interpret
> this as indicating a climbing habit.

Xu says that the foot structure indicates a ground-living ancestry. 
One interesting suggestion from Xu is that Microraptor may have been 
neither purely arboreal nor ground-dwelling. Suppose it was something 
cat-like which dashed up the trees when it saw something interesting 
and edible up there.

Microraptor was obviously far later than Archaeopteryx, but they seem 
close. Suppose the common ancestor was a Microraptor-like animal 
adapted for predation both on the ground and in trees, so it never 
truly gave up ground-dwelling but spent a significant part of its 
life in the trees. The ability to glide down from the trees might 
offer an evolutionary benefit, giving an advantage to any dino-bird 
with flight feathers. Perhaps it started by extending pouncing range 
from tree limbs.

It's just a thought, but I think Xu may be onto something.
--
Jeff Hecht     Boston Correspondent    New Scientist magazine
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