Re: Extinction

["philidor11" <philidor11@snet.net>]

>>The bolide impact happened at exactly (to within every determinable error
margin) the time when there was a massive faunal/floral turnover and
extinction across a wide variety of habitats and taxa, including
microorganisms, plants, invertebrates, and vertebrates.<<

Please remember that no dinosaur fossils have been found close to the K/T
boundary.  A mathematical analysis has demonstrated that there might still
have been dinos extant to go extinct at impact, but the same analysis
demonstrates equally that some remnants might have survived for some time
afterwards.

>>A global extinction such as that observed at the K-T boundary requires a
global cause; it cannot be the result of a coincidence of a multitude of
individual lesser local
extinctions--one kind of bird outcompeting another kind of bird at just the
same time that, say, sauropods in South America succumb to some kind of
disease and, say, European ornithopods are terminally devastated by mammals
eating their eggs and, say, volcanism wipes out the abelisaurs in India.<<

'...cannot be the result of a coincidence...'?  Less ...um... parsimonious
than a single cause, yes, but probability does not preclude coincidence.  If
you want to rule out coincidence in principle, then first you have to find
direct evidence of an impact at the time of each major extinction.  The
argument that simultaneous extinctions prove impacts because impacts produce
simultaneous extinctions is false without a demonstration that in reality
ONLY impacts can produce simultaneous extinctions.

 >>This is the kind of global event required to produce a mass extinction.
When you have a corpse lying in a pool of blood on the floor with a smoking
pistol nearby, your working hypothesis should not be "death from cirrhosis
of the liver."<<

Even the existence of a 'global event' is not sufficient.  That is, has
global severity sufficient for complete extinction of widespread species
been proven?
Finally, looking at your metaphor, as far as I know we don't have the
fossilized corpse(s), and, as a mystery fan, I know that the obvious is
frequently overthrown.  I'd read on before I was sure the blood belonged to
the victim.  If my working hypothesis is 'possible death by misadventure'
can you gainsay me?