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Re: Testing competitive exclusion in birds, bats and pterosaurs



--- Tim Williams <twilliams_alpha@hotmail.com>
schrieb:

> Jim Cunningham wrote:
> 
> >Birds developed the specializations for marine
> soaring flight within 5 
> >million years of the demise of pterosaurs
> (different requirements from 
> >terrestrial soaring).  I think a speculative case
> could be made that 
> >pterosaurs may have been excluding birds from this
> niche.
> 
> I agree with you on this point.  The group you're
> referring to 
> (Odontopterygiformes) were marine soarers in the
> Paleocene.  Although there 
> is indirect evidence that that this group may have
> been around in the later 
> Cretaceous (see
> http://dml.cmnh.org/2006May/msg00247.html), there is
> no 
> direct fossil evidence of any marine soaring birds
> at this time.  Then 
> again, we haven't yet discovered any
> odontopterygiforms at all from the 
> Cretaceous, so we just don't know how early they
> became marine soarers.

I'd like to see a reanalysis of the Odontoanserae for
a number of reasons, but until then, "possibly... why
not?" I'd say.

As per Bourdon (2005): "The placement of the
pseudo-toothed birds close to the Anseriformes shows
that their resemblances with Pelecaniformes or
Procellariiformes are superficial." - well, as it
appears, the Pelecaniformes and Procellariiformes
themselves are each united by superficial
"synapomorphies". No comment from Mayr or the likes,
only referenced in Livezey/Zusi's big one.


Jumping topics shamelessly: what would happen under
PhyloCode if the Odontoanserae turned out to be an
artefact?


Regards,

Eike


                
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