Article View: sci.astro
Article #4202Rate of Extinction (was Re: Asteroids and Dinosaurs )
From: James S. Larson St. Olaf College
Date: Mon, 22 May 1989 22:22
Date: Mon, 22 May 1989 22:22
25 lines
2006 bytes
2006 bytes
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. -- ------------------------------------------------------------------------------- | Jim Larson | "What? You mean behind the rabbit?" | | larsonjs@thor.acc.stolaf.edu | -Monty Python and the Holy Grail | -------------------------------------------------------------------------------
Technical Details
Message-ID:
<2210@thor.acc.stolaf.edu>Path:
arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ukma!xanth!nic.MR.NET!thor.acc.stolaf.edu!larsonjsReferences:
<256@ringwood.Morgan.COM> <3200009@hpindda.HP.COM> <1212@irisa.UUCP> <40227@bbn.COM> <1519@optilink.UUCP>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!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