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The roaches shall inherit the earth (was RE: (extinction))



 
John Bois wrote:

> I am just skeptical of estimates of the power global devastation on one
> hand, and the inability of some clades relative to others to withstand
> them.  

If ten bolides hit the earth 65 MYA, rather than just one, we wouldn't be
having this conversation.  Firstly, none of would ever have been born.
Secondly, the extinction would have been total, and there'd be no arguments
about 'targeting' or 'blind selection'.  As it was, there was one bolide,
and certain organisms survived the destruction to carry the banner of their
respective clades across into the Tertiary.

Imagine this: Nuclear war breaks out tomorrow.  Nuclear missiles rain down
everywhere, killing most of the life on this planet.  The only survivors are
me, John Bois... and millions of cockroaches.  I claim the bombs were
responsible for the destruction.  No, says John Bois, the cockroaches ate
everything - including most of the human race.  Otherwise, why would just
the cockroaches have survived but almost everything else gone extinct?



Tim















Clearly, when Lillegraven, Eberle, Currie, examine these horizons
and can hardly tell when one starts and the other stops...well...and, in
other locations, Horner looks and finds changes afoot earlier than dogma
suggests, and when Ir turns up in inappropriate levels...these may all
be
justified in the end and brought in line with the bolide idea (like
Darwin's hypothesis for the formation of coral reefs!)...we'll see.

> Because lepidosaurs, eusuchians,
> champsosaurs, chelonians, mammals and neornithines all survived across
the
> K/T doesn't mean they were immune, and therefore not 'targeted'.  The
entire
> 'targeting' thing (or 'blind selection') is beside the point.

Well, not really.  Is Archibald's claim that placental extinction in NA
were almost all pseudoextinctions still supportable?  When some
creatures
in NA enjoy nearly 100% at the species level and other buy it
completely...then one has to begin to think of reasons, to make
inferences
from this pattern.

> And the iridium spike at the K/T boundary?  And the Chixculub Crater?
> Circumstantial, perhaps?  Maybe something collided with the earth
about the
> time that placentals decided to kick some marsupial ass, and the
> neornithines elbowed out the enantiornithines, and a whole bunch of
marine
> invertebrates suddenly went to meet their Maker.  This, if I
understand you
> correctly, is your hypothesis.

Paleontological conclusions should be drawn from the totality of the
evidence.  I'm just saying that I don't find the terrestrial vertebrate
evidence convincing.  Attempts to make it so seem shoe-horning and
resort
to circularity.  Specifically, however, we have seen marsupial ass
kicked
before...and we are witnessing marsupial ass being currently whupped in
Australia as we speak; and, we currently have no hypotheses for the
elimination of enantiornithines should it turn out that they were
selected.  Indeed, other hypotheses enjoy better evidenciary
support: pterosaurs were practically gone by then and we need a
non-bolide
targeting killer for them.  It should have wings (because flying things
can take refuge from non-flying things), and it should be a new species
(otherwise it would have happened before).  And, so I ask: would it
change
your mind if it were KNOWN that neornithines played the leading role in
these extinctions?