Re: The End of Dinosaurs

[shasta@rmii.com]

>    Charles Pellegrino suggests this "co-factor" in dino extinction:
>     During the dino era much of N. America, Europe, Asia, and Africa
>were under water. And this high ratio of water to land surface
>established a mild climate that dinos thrived in.
>    Then volcanic activity at the mid sea ridges subsided. The ridges
>began to sink under their own weight, draining water from the
>continents. As sea levels fell, oceanic and air currents were changed
>drastically by the newly exposed land, with dramatic effects on
>climates. This might have been a "major cofactor" in dinosaur
>extinction.
>     Source: Pelligrino, Charles. Unearthing Atlantis. New York:
>Random House, 1991.

Call me crazy, but I have some doubts as to the credibility of this
theory.  It remimds me of an experiance I had while waiting at the
line in a grocery store.  As there happened to be a few people in
line, I browsed around at the tabloid magazines.  One headline jumped
at me, proclaming "Scientists plan to eliminate seasons by blowing up
the moon".  Bear with me here.  :-) Anyway, it said that by blowing up
the moon, "scientists" would place explosives so a peice hit the
earth, and changed the angle of its axis, eliminating the seasons.  As
my mind wondered, I condidered the [vauge] possibility of an asteroid
impact doing the same thing to our fair planet 65 ma.  Hypothetically,
the asteroid could have titled the earth's axis to a more acute angle.
This thory falls apart about as fast as a house of cards.
        There is a point, though.  I think that my short-lived theory of the
dinosaur extinction is on the same plane as the one mentioned above.

>    Then volcanic activity at the mid sea ridges subsided. The ridges
>began to sink under their own weight, draining water from the
>continents. As sea levels fell, oceanic and air currents were changed
>drastically by the newly exposed land, with dramatic effects on
>climates. This might have been a "major cofactor" in dinosaur
>extinction.

        Is there anyone out there who knows much about plate-techtonics?  Is
this continetal movement recorded in the history of our planet?  Plus, the
dinosaurs were tough.  Spartans.  Virile.  I don't think that minor climate
changes (the dropping of the continents) would have killed off the
dinosaurs.  Keep in mind that we have found hadrosaurs in Alaska, which even
in the cretaceous, was somewhat cool.  However, another thing to consider is
that other animals living at the same time as the dinosaurs (i.e. small
mammals and reptiles) would have been more likely to have died out with the
dinosaurs.  Then again, I could be wrong.  Maybe it was the dinosaurs
*destiny* to die out (not!).  :-)