Re: Evolution, "adaptation", and what's currently adaptive

Bryant (
23 Aug 1996 08:28:44 -0600

In article <>,
Len Piotrowski <> wrote:
>I suppose by asserting a "jealousy instinct" and "sugar craving" that you
>have, by some slight of hand, explicitly demonstrated the evolutionary
>significance of these "behavioral traits" for some purported ancestral human

I have not, of course. As should be obvious, explicit demonstrations of
the fitness effects of a given trait to our ancestors is quite impossible.
It would be equally impossible to demonstrate explicitly that the human
heart increased ancestral fitness.

Some reasoning, however, should quickly suggest that glucose is an
important limiting resource for us big-brained creatures, and that jealous
behavior likely had fitness effects in our ancestors' lives.

By the way, for lurkers & others: "fitness" in evolutionary discussions
means "reproductive success," or ~how many copies of ones genes get passed
along to subsequent generations.