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RE: New Cretaceous bird and other papers



> It is IMHO no stretch to assume that...
>
> ...there were enants everywhere in the world except in Antarctica in the
> Maastrichtian. Evidence: All known birds from the Maastrichtian site on
> Seymour Island (next to the Antarctic Peninsula) are Neornithes.
> ...the effects of an impact depend on latitudinal distance. Then
> Antarctica
> is as far as you can get.
> ...100 % of non-neornithines died out, along with (guesses) 99 % of
> neornithine species and 99.999 % of neornithine individuals.
> ...100 % of Neornithes died out everywhere north of (guess) 20° south.
> Allows for survival of ratites in New Zealand, Madagascar and India as
> predicted (but maybe not necessary, assuming that the ratites of that time
> were not flightless) by the newest mtDNA phylogeny of ratites.

*milk shoots out through nose*

99.9999%?!?!?! 100%?!?!?!? *That* is the definition of "stretch".

Dude, one look at the data from the most extensively sampled and best-known
K/T boundary sites in the world (Hell Creek-->Tullock, Lance-->whatever)
should tell you that these numbers are, um, slightly inflated. In the
Puercan, we find animals not only in the same genera, but often a sister
species, if not the same one! These are mostly mammals and "lower"
vertebrates. Birds are very rarely found either before or after the K/T so
it's tough to draw any conclusions. But what's a scenario where survival of
so many groups of amphibians, lepidosaurs, crocodiles, and mammals of all
stripes approaches 100% at the "generic" level, but every single bird in the
same area is summarily wiped out?

Q: Why do multituberculates scoot through a huge extinction event virtually
untouched, then peter off for seemingly no reason in the middle of the
Oligocene?

Point is, we really don't know what happened yet.

Mike D.