Re: K/T birds

[Graydon <graydon@dsl.ca>]

On Tue, Dec 18, 2001 at 10:51:58PM -0500, John Bois scripsit:
> I mean, presumably there is a great range of tolerance among the putative
> bird survivors; and certainly a similar range existed for non avian
> dinosaurs--was there no overlap, or was extinction event so precise so as
> to intersect the precise division between the two taxa--that is a surgical
> strike, indeed!

The only fully terrestrial species that make it over the KT are small
opportunistic feeders; the non-avian dinos didn't have much in that
category, since the ecosystems looks to have been heavily biased towards
large specialized feeders.

That's all it takes, really; if someone finds a Cretaceous ratite that's
ostrich sized, rather than turkey sized, this is falsified, but I don't
think they're going to.  If the full theropod genetic diversity was
available afterwards, the expectation would be therizinosaurs, not moa.

-- 
                           graydon@dsl.ca
               To maintain the end is to uphold the means.