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

Bryant (
29 Aug 1996 15:32:07 -0600

In article <>,
Len Piotrowski <> wrote:
>In article <502e7h$> (Bryant) writes:
>This is all well and good, but as I've made clear, the problem that arose was
>with your "sugar craving" and "jealousy" traits as apparent counter examples.

I thought that I pulled those from my hat to illustrate (crudely) how
once-adaptive traits need not be currently adaptive. I think I was
critiquing problems with optimality models (something Gould and I agree
about), not attacking Gould.

I could be mistaken, but I thought that you pulled the various quotes
from different msgs and put them together to show that I was being
inconsistent by saying Gould overstates his case and then daring to
speculate about the adaptive function of sugar craving and sexual jealousy.

>>[snip] The male nipple has no apparent likely fitness effects.
>>It is probably a developmental side-effect of some kind. Baggage.
>Then I guess you would agree that there are other possible processes
>accountable for the existence of these "traits."

Of course. How many times must I say I'm not Dr. Pangloss before you'll
believe me?!

>These were juxtaposed in context with the Gould & Lewontin critique, not,
>interestingly, as examples of "functional design," but as an apparent counter
>to Gould & Lewontin's claim. I merely pointed out that they *were* examples of
>"functional design," something to which you took some exception.

I think I just communicated poorly. And perhaps misunderstood your point.
I think that the adaptationist program is sensible; look for a functional
"purpose" for a trait before dismissing it as the result of non-selective
forces of evolution. It's easier, usually, to test the predictions
derived from adaptationist hypotheses than from hypotheses which posit
that a trait has no functional significance.