Re: NANFA-L-- Kin Selection
Wed, 16 Feb 2005 13:56:25 -0600

> > Of course, it is possible that the behavior is not overridden
> because in real
> > life situations in nature, any eggs or fry encountered are
> likely to be
> > closely related.
> >
> I don't know if I agree with this, but it depends on how we regard
> closelyrelated.

I don't know if I agree with it, either, but many nest guarding fishes, like darters, sunfish, catfish are fairly sedentary. And yes, as you mentioned, some darters, sculpins, and even minnows (_Pimephales_ specifically) will take over another male's nest to get the eggs to entice females. Some darters may (jury out on this) have egg mimics on their dorsal spine tips that may help to convince females that they are good papas.

But, hmmmmmmm ..........

>Obviously, there's an advantage to a species in
> protecting all members
> of the species, regardless! \

".... an advantage to the species ........ "

To the degree that natural selection drives (and I agree that all the other things you mentioned are important (though some of them, like kin selection and sexual selection, are simply specific iterations of natural selection), I think many evolutionists will agree with me that it is unlikely that there is any advantage to protecting all members of the species. In fact, intraspecific competition is likely very important in natural selection. If protecting unrelated members of ones species was an advantage, then natural selection wouldn't work, and there would have been no century long effort to try to explain altruism. Understood that Saint Stephen Jay Gould was a big proponent of species selection, but not in the traditional selectionist sense, but rather as a paleontological phenomenon.

BTW, I just read that (didn't know this before) introduced mosquitofish are serious predators on California newt larvae, despite the fact that the skin of one california newt (adult, admittedly, far too big for a mosquitofish to eat!) has enough of a chemical almost identical to tetraodontitoxin (from puffers)to kill 25,000 mice or one adult human. A larva would have less, obviously, but the article mentioned that mosquitofish being introduced, the newt has no evolved defenses for this predator.


David L. McNeely, Ph.D., Professor of Biology
Langston University; P.O. Box 1500
Langston, OK 73050; email:
telephone: (405) 466-6025; fax: 405) 466-3307
home page

"Where are we going?" "I don't know, are we there yet?"

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