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



It's true that they refute Feduccia's extreme version. Fossil evidence for a
diversification of Neoaves in the K is however still lacking, as the article
itself stresses.

"Extreme version"????

In 1996 at least, Feduccia thought that the crown-groups of Palaeognathae and Neognathae were entirely Cenozoic. (Can't live with a Cretaceous duck.) A less extreme version is the idea that only the crown-group of Neoaves, or only those of, say, Metaves and Coronaves, are Cenozoic-only. (Can live with K ducks, but not with K parrots.) The opposite is what the molecular divergence date estimates of the last 10 years say: that most if not all divergences between the extant bird "orders" happened in the Cretaceous. (Requires both K ducks and K parrots.)


Birds should have been affected as badly as non-avian dinosaurs.

Why do you think so? Most birds have advantages on their side that most other dinosaurs lacked:
- Small size. Means, large populations, low food requirements, easier to find shelter...
- Flight. Means the ability to cheaply cover vast distances in search of food, mates, nesting sites and whatnot. This in turn means that much fewer individuals per continent need to survive to continue the species.
- Ability to live off seeds (Galliformes, Palaeognathae).
- Ability to live off insects (Galliformes, Palaeognathae, who knows what else).
- Being part of ecosystems that aren't based on living plant parts (especially in freshwater; Anseriformes, whatever).


The more species we find that are ancestral to extant species, the
less support there is for an instantaneous, all-encompassing catastrophe.

Evidence for Cretaceous members of Neoaves -- a huge clade! -- is still quite poor. Besides... the more species we find that are _not_ ancestral to extant species, the _more_ support there is for an instantaneous, all-encompassing catastrophe... and this, too, is going on now, partly by new finds (the toothed bird of Maastricht, *Limenavis*...), partly by revisions of known specimens (*Iaceornis*, probably *Polarornis* and *Neogaeornis*...).