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Microraptor hanqingi, new species from China.
> Again, I actually like the idea - since you're the one who pointed it
out here, I was hoping you had some suggestions for what we'd predict if
tree-roosting was indeed important to paravians.
The idea was never advanced by me as a testable lifestyle for any
particular fossil specimen -- that would be a "misunderstanding" -- but
it falsifies the idea that an animal evolving flight in tree-down
gliding-first mode will by evolutionary logic show "arboreal
adaptations" in its skeleton -- beyond the basic capacity to climb a tree...
I suppose predictions made by tree-roosting might include 1) limited
upstroke early on (that is, even after the appearance of a sophisticated
gliding wing), 2) that the perching foot would appear subsequent to
powered flight (full upstroke), not before -- and 3) the capability of
One note -- controlled climbing up is easier than climbing down -- and
in the hoatzin type wing-claw model, climbing down would appear to be
problematic, which makes parachuting/gliding useful.
In any case, I am unsure that these are unique predictions, and would be
useful in "proving" tree roosting -- although I suppose in sum they
might be a start.
Given that the possibility of a tree-roosting lifestyle falsifies
certain assertions about the relevance of "arboreal adaptions" to bird
flight evolution, I think any statements that the "discussion" was not
fruitful are wrong.
> If your assertion is, instead, that we'd see no difference in the
fossil record between a case a fully "terrestrial" origin and a
"terrestrial + tree roosting" origin [...]
Yes, that is my assertion, but relative only to pes morphology in small
cursorial, feathered, vertical-climbing, etc, etc...
I would think a strict ground-up scenario might predict a full
wingstroke early on, even when wings are rudimentary -- but suppose that
to be debatable.
Foraging in a tree would necessarily alter the feet, by evolutionary
logic -- but just sitting or sleeping in a tree will not necessarily do
so, especially given a ground-foraging lifestyle and the attendant
conserving of cursorial morpho-type.
> then I'm not sure what is being argued.
You could comb through the various threads and find other people to ask
-- apparently no paravians would or could roost in trees, sauropods and
tall theropods would pluck them off branches like so many peaches, any
"rooster" would fall off and die when sleep came (yet could pounce on
prey from the same branch with great success), and my personal fave,
sickle-type claws would shear through any branches they gripped like