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Re: Hell Creek -- new research underway



On Thu, May 30, 2002 at 08:51:50AM -0700, Rob Gay sent:
> >Some life forms were not affected at all, it would appear -- again, why? <
[key factor is torpor?]

I think this involves a scale error in thinking about the impact effects.

The problem is not surviving the immediate impactor effects; those are
mostly a you-do-or-you-don't, dumb luck sort of thing.

The problem is how your lineage survives the (at least) tens of
thousands of years while some other stable ecology establishes itself;
big things die, not because they can't move, hibernate, cope with the
climate change, or whatnot, but because they simply cannot get enough
food in a simplified ecology with a reduced carrying capacity.  (Or,
likely, _enough_ of them can't and some statistical fluctuation wipes
them out.)

The common angle of (terrestrial) survival looks a lot more like
insectivory than anything metabolic; the range of surviving metabolisms
ranges from bugs to birds, after all, without any obviously distinct
distributions in relative rates of survival based on metabolism,
especially when doing something like consisdering survival within
mammalian groups.

-- 
graydon@dsl.ca   |  Hige sceal þe heardra, heorte þe cenre,
                 |  mod sceal þe mare þe ure maegen lytlað.
                 |   -- Beorhtwold, "The Battle of Maldon"