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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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