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Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!ut-emx!ethan
From: ethan@ut-emx.UUCP (Ethan Tecumseh Vishniac)
Newsgroups: sci.astro,sci.space,sci.space.shuttle
Subject: Re: Asteroids and Dinosaurs (was Re: asteroid almost hits earth)
Summary: iguanas and turtles are not dinosaurs
Message-ID: <13111@ut-emx.UUCP>
Date: 17 May 89 14:42:34 GMT
References: <256@ringwood.Morgan.COM> <3200009@hpindda.HP.COM> <1212@irisa.UUCP>
Organization: The University of Texas at Austin, Austin, Texas
Lines: 27

In article <1212@irisa.UUCP>, saouter@irisa.UUCP (saouter yannick) writes:
> 
> - Moreover Iridium is poisonous.

In sufficient quantities it is.  In this case the amounts are probably not
biologically significant.

> 
> However, all the dinosaurs would have been to disappear, that is to say, even
> turtles and iguanes. And when all the creatures to be killed, then a great time
> would be needed to repair this catastrophe (the first oxygen producers appears
> in the sea 2 000 000 000 years ago, and this hit occurs 65 000 000 years ago).

Actually, turtles and iguanas are not dinosaurs, and they did not disappear
at the end of the Mesozoic.  My understanding is that the extinction of
terrestrial life can be summed up with the statement that everything weighing
more than 20kg died off.  However, the extinction was more sweeping than
this and many tiny  (and, of course, large) oceanic organisms died as well.
It is also true that this is not the most dramatic mass extinction in the
fossil record. 
-- 
 I'm not afraid of dying     Ethan Vishniac, Dept of Astronomy, Univ. of Texas
 I just don't want to be     {charm,ut-sally,emx,noao}!utastro!ethan
 there when it happens.      (arpanet) ethan@astro.AS.UTEXAS.EDU
    - Woody Allen            (bitnet) ethan%astro.as.utexas.edu@CUNYVM.CUNY.EDU

These must be my opinions.  Who else would bother?