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Re: Ornithurine diversity
> Well, if ornithurines had speciated to the point of greater
> due in part to competative replacement/exclusion of
> then their higher species count and larger range of
> ecomorphs would
> have made them statistically less likely to be totally
> wiped out.
True, but the most specialised ornithurines (Hesperornithes) did not survive -
not that I'd expect specialized forms to survive an ecosystem collapse. And
overall, the entiornithine diversity was probably still higher.
More parsimonious explanations might be that (especially Gondwanan) part sof
the globe which were less affected by the impact(s) hat actually a higher
diversity of Neornithes still. I am mainly thinking of the Australia-NZ-Byrd
Land triangle, which was as it seems may well have been settled by basal
Neornithes *before* Enantiornithes arrived there in numbers - if they ever did.
But there is just too little material to tell (it stands to note that
_Nanantius eos_ was apparently a seabird, which is unusual for an
enantiornithine). From the simple standpoint of parsimony, even the apparent
lack of a proper fanning tail (unknown in enantis this far) might be
considered, though I really have no idea how that should help to survive...
That being said, it IS an important study. Conclusions might be premature or
not, but anything Campanian/Maastrichtian that looks ornithurine is well worth
a publication in its own right in this listmember's view. There is much insight
to be found in these bones, for they will tell us more about how what we know
as birds today birds came to be.
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