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RE: Sheesh



> Honestly, to do so is to just be wrong.

At least until the full fallout of Mayr et al's study
of the Thermopolis Archie has settled in. I'd rather
like to see Confuciusornis removed from Aves sensu
stricto than Deinonychus included in it...

> Why did no dinosaurs become marine until the
> advanced ornithurines? (E.g., hesperornithiforms and
> various neornithines)

Hesperornithids, penguins, plotopterids, and
mancalline auks, Pinguinus and Chendytes as borderline
cases. Did I forget any?

I can see no clear pattern here. Not even competition
by marine mammals spelling doom - this seems to hold
true for flying seabirds (whether the "Late
Pleistocene supernova" theory is correct doesn't
matter - seabirds simply couldn't get a hold on their
habitat as they did before marine mammal
diversification). Competition by marine mammals does
prevent truly marine birds which are also carnivores
from evolving, but that's no reason for why the
Hesperornithes disappeared (which was some time before
the C/T, IIRC).

So what one can say with certainty is that there were
no truly carnivorous lineages of truly marine birds
(as opposed to flying seabirds) around when and where
there was a large diversity of marine mammals.

Regards,

Eike


        

        
                
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