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Re: 11th specimen of Archaeopteryx
> Secondly, if theropods *routinely* spent time in trees we might
> expect to see arboreal specializations.
Not if the time spent was unrelated to locomotive activity. As in,
roosting -- but not foraging, mating and etc.
This is nonsense. If you need to hold tree branches for a living (as in:
not falling down when you sleep), there will be natural selections for
adaptations that make this easier and against, say, cursorial
adaptations that make it harder.
So I disagree strongly -- arboreal specializations are NOT expected
in an animal that roosts, but otherwise pursues it's daily (or
nightly) business in cursorial fashion on the ground.
Grasping specializations, however, _are_ expected.
Assuming constrained powerstroke
The powerstroke is the downstroke, not the upstroke. The upstroke, which
gets the wings out of the way of drag as much as possible before the
next downstroke, is what was (apparently) limited in Archie and
Note that all the clever ground-based activities advanced over the
years (fighting, leaping, brooding and etc.) nestle neatly into a
GFTR lifestyle -- possibly all at once in the same animal.
They don't contradict the TR part. Archie's skeleton does, and so does
(to a slightly smaller extent) that of *Microraptor*.
BTW, you mentioned trees taller than 3 m. Precisely such trees appear
not to have existed in Archie's environment, unless all known
individuals were blown in from the presumably forested Bohemian Mass 200
km away and didn't live on the small islands in the lagoon. -- Of
course, this doesn't apply to *Anchiornis*, *Xiaotingia*, *Microraptor*,
or any other of the Chinese beasties.