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Re: Vegavis gen. nov. - new anseriform in today's Nature



Graydon <oak@uniserve.com> wrote:

More or less what they are now -- jungle fowl.  And even modern domestic
chickens will eat anything, up to and including attempts on the toes of
anyone so incautious as to wear sandals near them.

Also note that it's plenty if *one* proto-chicken and *one* proto-goose
species make it over the boundary, to explain the present observed
diversity.

The paper concludes by saying "The Anseriformes that can be inferred as present by this point [Maastrichtian] are lineages that today include large-bodies terrestrial browsers and occasional omnivores (that is, screamers, Anhimidae and magpie geese, _Anseranas_) as well as the lineage leading to true ducks and geese."


To this we can add the first galliforms, the first paleognaths and (perhaps) the first dromornithids, based on phylogenetic divergence; and perhaps loons (based on _Neogaeornis_ and _Polarornis_). Interestingly, in today's world all of these groups (galloanserine birds, loons, paleognaths) are not among the most accomplished or powerful fliers - some don't fly at all. Maybe (and this is a big MAYBE) it was advantageous to be able to fly (by allowing an expanded area for scavenging or foraging), but having a metabolism that was adapted for the demands of high-speed flight imposed a prohibitively high energy cost on these birds.