larsonjs@thor.acc.stolaf.edu (James S. Larson @ St. Olaf College) (05/23/89)
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 | -------------------------------------------------------------------------------