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RE: Arboreal Theropods: The prize at the bottom of the cracker jack box
I didn't say arboreality.
I am not finding measurements of the manual claw curvatures of Epidendrosaurus
but the curvatures don't look weaker than in Opisthocomus.
From: owner-DINOSAUR@usc.edu [owner-DINOSAUR@usc.edu] on behalf of Jason
Sent: Sunday, July 21, 2013 4:16 PM
To: firstname.lastname@example.org; "\"email@example.com\"@listproc.usc.edu"@listproc.usc.edu
Subject: RE: Arboreal Theropods: The prize at the bottom of the cracker jack box
One more possibility occurred to me today.
Though Dr. Habib assures us, and I believe him, that even gliders use leaping
to gain their initial velocity, and that nothing just drops from an elevated
position to gain gravitational acceleration, there is a pattern with some sea
Procellariiforms (petrels) lack halluces and they nest on the ground (though
tree nests of Pelecanoides have apparently been reported). When fledging the
chicks of several species climb trees, in some cases favoring those that are
tilted at 30 degrees to vertical, and then launch out to sea from this elevated
Another group of birds with no halluces - murrelets (Marbled Murrelet) - may
nest on branches in very tall old - growth trees. Before they can fly the
chicks spend many weeks on the branches, snapping at insects, preening,
flapping their wings, and so on. When ready to fledge the chicks leap from
these branches and may fly over 30 km. I wouldn't call marbled murrelet chicks
arboreal, yet they do successfully occupy tree canopies.
I come to two conclusions.
1) Birds with no halluces still use trees as crucial habitats in their biology.
2) Trees may even be important to birds that nest on the ground and forage at
sea! Now there's a category outside of G and GB for you!
In any case, there is the possibility that basal paravians utilized trees in
similar ways, to assist them in gaining range on fledging or on flights (or
glides) as adults. This could be true even if they were distinctly NOT arboreal
in foraging or nesting.
asal paravian evolution. I am not trying to put them in trees. I have tried to
demonstrate that there are exceptions to the rules that others have cited in
claiming that such ecomorphologies were IMPOSSIBLE for animals without
unambiguous specializations. Thus I have tried to promote the proper scientific
uncertainty and open - mindedness on this issue.