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RE: Purple Paleo Prose Down Under



Christopher Taylor

In all the studies I've seen more recently
(both morphological and better molecular methods), _Anseranas_ has
returned to its position as next basalmost living anseriform after
screamers. Still, _Anseranas_ is a lot more reminiscent of a screamer
ecologically than any other Anatidae s.l.

Thanks for the clarification, Chris. I know the analysis of Clarke et al. (2005) recovered _Anseranas_ as the sister taxon to Anatoidea (including _Presbyornis_ and _Vegavis_), and more derived than anhimids. The screamer + magpie-goose ecology might be primitive for the Anseriformes. So it's not surprising that dromornithids, if they are basal anseriforms, conform to this ecology too.


Some studies put gastornithids (diatrymids) among the anseriforms too, or at least somewhere close. Gastornithids appear to be at the center of the same argument over their feeding habits as dromornithids, for much the same reason.

    In relation to dromornithids, analogy with other living anseriforms/
Galloanserae would suggest a largely omnivorous diet - primarily
vegetable matter, but a reasonable amount of animal food where
available.

Such an ecology might be primitive for the entire Neognathae clade. Just wondering...


*My comments on the unreliability of DNA-DNA hybridisation are in no way
a condemnation of Sibley et al. for using them. Molecular methods of
looking at relationships were still in a very primitive state, and
hybridisation was probably just as good as any other technique available
at the time.

Certainly. Nowadays, techniques like PCR and DNA sequencing are fairly standard, as is phylogenetic software and the computers needed to run them - though not necessarily inexpensive (for all of the above). Thus, DNA-DNA hybridization has fallen by the wayside.


Cheers

Tim