> While I am in full agreement of warming world - so are the other planets.

Some are and some aren't.  Like the Earth, other planets have cycles.
There's no need to worry the possibility that the Sun is starting to
become a giant that will cook the Earth, so mollusk conservation
remains a valuable activity.

>The great Ice Age all but did in the world

Apparently the biggest Ice Age for Earth actually occurred in the late
Precambrian and was promptly followed by the diversification of
animals, including the first mollusks.  A few other major ice ages
have come since.  The latest, which we are in a warm phase of at the
moment, eliminated the last non-marine mollusks from Antarctica,
caused widespread extinctions in marine mollusks in eastern North
America (but new species have largely evolved to replace them), etc.,
but was not a serious risk to life generally.  The Little Ice Age is
late Medieval to a couple hundred years ago; major volcanic eruptions
in the 1800's produced a couple of cool years.

> Since we are now in an elliptical orbit from the normal near round
> we can expect a cooling trend and perhaps another baby ice age
> as we swing further away.  I think the recent alignment of four
> planets (and our Galactic center!) had something to do with the
> orbit change.

Actually, the Earth's orbit has always had several long-term wobbles
in the orbit, including more oval to more circular, the tilt of the
rotational axis relative to the orbit, and the point in the orbit at
which the rotational axis points a particular way relative to the
Sun-the Milankovitch cycles.  These take tens of thousands to hundreds
of thousands of years to complete.  By affecting the earth-sun angle
over a year and, to a lesser degree, the distance, they affect the
temperature and thus the climate.  They also provide a handy
chronometer for precise (by geologic standards) dating of fossil
deposits.  Data from mollusk shells can help calibrate this.

The problem with current global warming as far as most organisms are
concerned is the speed of change.  If global warming is allowed to
continue unchecked (until we run out of petroleum), after a few
million years the faunas would probably recover assuming we didn't do
anything worse for the environment.  Mollusks have done pretty well in
recovery from mass extinctions.

--
Dr. David Campbell
425 Scientific Collections
University of Alabama
"I think of my happy condition, surrounded by acres of clams"

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