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Re: New Mesozoic bird papers (advance publication)
2) from page 3 "The earliest ornithurine birds resemble shorebirds
and presumably occupied an ecological niche with few trees". The
problems with these unsupported hypotheses were discussed 8 years ago
by Clarke and Norell (Morphology and Phylogenetic position of
Apsaravis ukhaana from the Late Cretaceous of Mongolia, AM Novitates,
Dec. 27 2002). They include Livezey's caution that the morphological
correlates of a shorebird habit are not well defined, and may be
pelsiomorphic in modern Charadriiformes. The discovery of a very
basal Ornithurine, Apsaravis, in the continental interior of
Mongolia, also calls the shorebird hypothesis into question.
Feduccia somewhat angrily replied to this (in Nature, I think) by
pointing out that gulls occur deep in continental interiors wherever
there are bodies of water. This is of course true. He did not, however,
try to find any morphological correlates of lifestyle in *Apsaravis*...
and neither had Clarke et al..
Just out of curiosity, is there any sort of inverse correlation
between degree of arm-feathering/'quality-of-flight' characteristics
and presence/size of claws in fossil remains? In other words, is
there reason to expect that the amount and type of feathering that
would be associated with increasing ability to fly would be
compatible with using the hands/claws to capture prey? I've seen
wings used to buffet and distract small prey, but I'm not sure I
would expect a winged arm to be terribly good at snatching at small
prey, as opposed to an unwinged or less-feathered arm.
Wings work fine with _big_ prey, because then they stay clear of the
ground. Remarkably, there is evidence that the tiny *Microraptor* hunted
just such (comparatively) big prey in packs; though this was only
presented at this year's SVP meeting and isn't really mentioned in the
abstract, so I can't say more. :-(