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Re: Diatryma and mammals!
> On Sat, 1 Aug 1998, Ronald Orenstein wrote:
> > PS - if diatrymids were indeed eurytropic, that argues against their being
> > restricted by mammalian competition - eurytropy is hardly a symptom of
> > competitive restriction!
> Yes. I would rather they were paludal.
An important afterthought: eurytropy is common in animals dependent upon
wetlands. But they need the deep cover of the marsh, pothole, swamp,
whatever, to reproduce. When this cover disappears, so do they. Indeed,
predation is a major source of nest destruction in waterbirds of the
prairies (ref. if needed) which are dependent upon potholes for nesting.
Also, if something did not prevent radiation of diatryma into more diverse
niches, a thoroughly reasonable expectation is that we would observe
adaptive radiation in that body plan! In the same way that we infer
mammalian influence in the inability of non-avian dinosaurs to compete in
the small mammal niche--at least some of us do--mammals would appear to be
the only viable suspects in this instance well.