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Bird and mammal K-T survival
We've been through this neornithine K-T survival discussion before, so
why is anyone still scratching their head for possible solutions?
It was probably partially luck that neornithines were among the few
bird survivors. Being in Antarctica or Australia would have been a whole
lot luckier than being in North or Central America. And being small and a
generalized feeder would also have been a good idea.
But I clearly think any one of three survival strategies could have
given neornitheans an edge (which non-ornithean theropods may not have had):
(1) living in a burrow and subsisting on insects, seeds, and/or
underground roots and tubers.
(2) living in a burrow and being in torpor (sleep through the worst of
it). This is a likely survival strategy for paleognaths.
(3) burying your eggs like a megapode, preferable in alkaline soil
(which would neutralize acid rain).
The third option was probably that which saved many crocodiles (and not
minding the ingestion of dead animals would have helped as well). Many
mammals probably survived using options one and/or two (and monotremes may
have used a combination of all three survival strategies). Most surviving
frogs were probably in torpor (frozen or dessicated in the ground), and
frogs are the ones that really gets most people scratching their heads.
I just don't think it is such a big mystery. The survivors of the K-T
catastrophe were lucky enough to be in the right parts of the world, in the
right niches, and being a generalist feeder certainly was another plus. The
same was true in the oceans, and those forms (like ammonites) which were
heavily dependent on plankton in some stage of their life cycle, were
goners. The generalist feeders did better there as well.
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