[lbo-talk] Re: Instinct

[boddi satva]

On 12/1/05, Miles Jackson <cqmv at pdx.edu> wrote:
> boddi satva wrote:
> > C. Miles,
>
> >
> > No evolutionary biologist would argue that traits which may tend to
> > reduce population fecundity are evolutionarily neutral.
> >
>
> I'm trying to think of some way to be tactful here, but I'm having a
> hard time.  I know the claim you make above seems obvious, but like many
> common sense ideas, it is contradicted by well-supported scientific
> theory.
>
> 1. Fecundity does not ensure reproductive success.  If people (say, oh,
> I don't know, people who only occasionally has heterosexual relations,
> like most gays and lesbians) have offspring and care for them
> effectively, their reproductive success could in fact be higher than
> people who kick out lots of babies but don't effectively raise them.
> Evolution does not select for fecundity; it selects for reproductive
> success.  Important distinction.

This would be a reasonable critique if it was actually a critique of
anything I said. My whole point has been that homosexuality may well
both reduce fecundity and increase survival.


> 2. Traits do not come as independent "packets" that all work
> independently to increase or decrease reproductive success.  A
> particular trait may be genetically linked to another ensemble to traits
> that increases reproductive success; thus the existence of some trait
> that appears to "reduce population fecundity" analyzed in isolation is
> in fact part of the constellation of traits that all together enhance
> reproductive success.

Again, if anything I said depended on the idea that "all work
independently" this would be a critique, but since I didn't, it's not.
We don't even know that homosexuality is a trait as such. We do know
that, as one effect of what may be a heritable trait, homosexuality
might reduce fecundity. Again, my whole point has been that the trait
or traits that produce homosexuality is/are positively adaptive.


> 3. The idea that natural selection only works at the individual level
> (if traits undermine an individual's fecundity, they will be selected
> out of the gene pool) is mercilessly ridiculed by serious evolutionary
> theorists.  A characteristic could enhance the reproductive success at a
> super-individual level (group, subspecies), and thus survive in a
> species, even if it reduces population fecundity at the individual level.

Again, if anything I said implied that "natural selection only works
at the individual level" this would be a valid critique. I didn't.
It's not. And you are really just repeating the point I made here.


> To be frank, this is pretty basic stuff in evolutionary theory.  I'm
> just an interested bystander (my main academic training is in psychology
> and sociology, not biology!); I'm sure a full-blooded evolutionary
> theorist could add dozens of other examples to my list.  In any case, I
> hope this makes it clear why your common-sense claims about evolution
> are dubious.

No, it's not only not clear, your point doesn't address the misreading
of Gould that you keep repeating. Again, Gould does not make the case
that gradualism doesn't exist and it is a reasonable assumption that
gradualist evolution might put pressure on a homosexual tendency.

boddi