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From: bzs@MULTIMAX.ENCORE.COM (Barry Shein)
Newsgroups: comp.society.futures
Subject: Lamarckian Genetics
Message-ID: <8811022014.AA01983@multimax.ARPA>
Date: 2 Nov 88 20:14:37 GMT
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I don't have a reference handy but basically Lamarck believed that
characteristics of a species could be handed down from generation to
generation based upon each generations experiences (as opposed to
Darwin's "natural selection" where the species changes because only
members with certain characteristics survived to reproduce.)

For example, a Lamarckian would claim that as lower leaves on trees
became scarce giraffes stretched to reach them. This somehow (a
mechanism has never been seriously proposed) is transmitted to the
offspring in the form of longer necks.

A Darwinian would claim that those giraffes who already had longer
necks got food and bore offspring, those with shorter necks died of
starvation and did not reproduce as much so their genes faded in the
population pool. Thus necks tended to get longer over many
generations.  Mechanisms for this are pretty well established, a
combination of random mutation and DNA based genetics.

Lamarckian evolution is not accepted by biologists today. There was an
article in a recent issue of Nature which apparently (I haven't read
it) reported something reminiscent of Lamarckian genetics at a
unicellular level. If I remember right bacteria who were starved of
certain nutrients "gave birth" to offspring which had (unusual)
digestive enzymes able to utilize other nutrients in an environment.

I (and others) are not quite sure that this is a proof that there is
validity to Lamarckianism, but it is interesting.

	-Barry Shein, ||Encore||