Re: Extinction and other...

[Betty Cunningham <bettyc@flyinggoat.com>]

One thing I noted several years ago to people on the list was the modern
preponderance of animals with a very primitive character -the pineal
gland.  Many modern groups share this remarkably primitive character,
and the list of animals that do share it OVERLAPS the list of animals
known to have survived the KT to a remarkeable degree. (frogs, crocs,
birds, mammals, etc)

If, as some people suggest, the pineal gland functions as a seasonal
clock, measuring hours of day vs night, a species with this capability
would not be dependant on the weather to indicate time of year or
season.  This would be vital in periods of unseasonal weather that may
have lasted for several years.

My supposition was that animals with functional pineal glands would be
able to breed at normal calander seasons, or remember to start seasonal
migrations, irregardless of long periods of unseasonal weather changes
due to a catastrophic meteor strike.  Animals dependant on weather
changes alone to indicate times to breed or migrate would be out of
luck.

So far in my lax investigations, late Cretaceous dinosaurs did not seem
to have the conformation of the skull that would allow light in to be
measured by the pineal gland.  The pareital area of most late Cretaceous
dinosaurs seems to have been very derived from earlier forms in each
type I've looked at.

This 'calander' factor added to the dice roll of surviving species would
weigh the survival chances of animals more capable of recovering a
normal schedule for survival, in addition to the varoius species that
could survive by sleeping it off.

-Betty Cunningham

> Joco Simues Lopes Filho wrote:
> About hibernation and burrowers. There are real proofs that all
> surviving primitive mammals hibernated? Arboreal proto-primates, like
> Purgatorius and relatives...they hibernated?
> It's like all mammals saying: "Oh, there's a meteor destroying our
> world! Let's hibernate!"
> But if it's true, there will be a pattern. Hibernating animals usually
> live on high latitudes. So, there would be survivors mainly in N North
> America, N Europe, S South America and Australia. Maybe. (And the
> polar dinosaurs from Australia?)
> Maybe I'm wrong, but I think studies about KT faunal transition come
> mainly from North America. There are other places where it can be
> studied? Where there wre  fossil records enough to reach some
> conclusion? Lower Paleocene in Europe is almost unknown, the same for
> Africa, Australia, South Asia.
> Dinosaurs were worldwide. Would any kind of disaster destroy all
> them?  I think some species  of dinosaur would survived in some
> isolated island, like Madagascar.

> 

-- 
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