Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ukma!xanth!nic.MR.NET!thor.acc.stolaf.edu!larsonjs
From: larsonjs@thor.acc.stolaf.edu (James S. Larson @ St. Olaf College)
Newsgroups: sci.astro,sci.space,sci.space.shuttle
Subject: Rate of Extinction (was Re: Asteroids and Dinosaurs )
Summary: Frightening...
Keywords: species extinction exponential lutefisk
Message-ID: <2210@thor.acc.stolaf.edu>
Date: 22 May 89 22:22:09 GMT
References: <256@ringwood.Morgan.COM> <3200009@hpindda.HP.COM> <1212@irisa.UUCP> <40227@bbn.COM> <1519@optilink.UUCP>
Reply-To: larsonjs@thor.stolaf.edu (James S. Larson @ St. Olaf College)
Followup-To: sci.astro
Organization: St. Olaf College, Northfield, MN
Lines: 25
Xref: utzoo sci.astro:4161 sci.space:11575 sci.space.shuttle:3194

There has been recent discussion as to the rate of extinction of species.
Some sources said that the rate was only a few dozen a century.  While
that may have been true in the past, the rate has increased dramatically
this century.

According to Gaia: An Atlas of Planet Management (edited by Dr. Norman
Meyers, 1984), the annual rate of extinction was less than 1 before
1900.  In 1950 it grew to 6/yr.  In 1975 it was 400/yr.  The projection
for 1990 was 10,000/yr. and the forecast for 2000 was 50,000/yr!!!!

They say "Current estimats suggest that we are losing one species a day
from the 5-10 million species thought to exist.  By the time human
populations reach some sort of ecological equilibrium with their
one-Earth habitat, at least a quarter of all species could have
disappeared."  (p. 155)

This is getting off the topic of the newsgroup, but it illustrates that
we don't need to wait for a one-in-a-million-years asteroid in order
to destroy life on earth.

-- 
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| Jim Larson			|	"What?  You mean behind the rabbit?"  |
| larsonjs@thor.acc.stolaf.edu	|	    -Monty Python and the Holy Grail  |
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