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Re: [dinosaur] Energetic cost of foraging flight in parrots

On Thu, May 18th, 2017 at 3:16 PM, Tim Williams <tijawi@gmail.com> wrote:

> The major fault I find with this particular model is that it assumes
> an arboreal setting.  If _Archaeopteryx_ and _Microraptor_ were indeed
> leaping between branches, one might expect them to have feet
> specialized for perching.  They don't.  The hallux is only modestly
> descended on the metatarsus, and it's certainly not reversed.  So it's
> difficult to envisage how an arboreal foraging protobird would land.
> Take-off is fine.  But without a foot that is adapted for grasping
> branches, the landing would be highly problematic.  

One thing I notice about the species of bird used in the study is that they have
unusually short tail feathers, which would seem to be an adaptation to leaping
about in closely-spaced branches. Most early theropod flutterers appear to have 
had long bony tails that would have made navigating such a cluttered environment
quite difficult, especially if the feathered tail 'frond' lacked the mobility 
of modern
bird tail feathers and couldn't be spread or retracted at will.


 Dann Pigdon
 GIS Officer
 Melbourne, Australia