In article <01bc3976$50366ec0$0a4892cf at mycomputer>,
Joe Potter <joe.potter at worldnet.att.net> wrote:
> The idea that you posit here assumes that the organism can see-ahead and
>determine what is best in the long run. This is a no-no, is it not?
It is a no-no.
> Dr. Eldredge wrote, " Selection can not be for the 'good of the species.'
>It can only be a measure of what works best for the individual organisms in
>their struggle for existence. ..."
Careful with the appeals to authority. I doubt Eldredge would deny that
species sometimes compete for resources. The presence of one species
changes the environment faced by another species. And I seriously doubt
that Eldredge would claim that environments, in general, remain constant.
Individuals of a sexually reproducing species may have greater reproductive
success in a given environment than individuals of an asexually reproducing
species. Selection is still acting at the individual level; nature does not
provide a guarantee to that at least one member of a species will always be
allowed to produce offspring.
> In other words, why sex??????
Why *not* sex? You've made the point that sexually reproducing
individuals only pass on 50% of their genes. Assuming that a population
consists of some sexually reproducing and some asexually reproducing
individuals, sexual reproduction is not expected to be fixed unless the
sexually reproducing individuals have substantially greater reproductive
success. Why is this not conceivable?
The fact is this: sex is *not* a problem for evolutionary biology.
Theories regarding why sex persists (a separate question from how sex
arose - which is also not a problem) are covered by any decent college-level
evolution text.
Rich Kliman
Dept. of Biology
Radford University
*standard disclaimer*
