The purpose of this thread is to state some of my objections to fitness and hopefully clear up some of my misconceptions about the concept.
I'd like to start with Quetzl's response to me in another thread, and go from there.
Right. I certainly haven't read anywhere that fitness is "just fecundity", so I'm not sure where you got that. Unfortunately, we're coming up to the end of this thread, so a long digression here may be counterproductive. Without getting into a very long discussion, suffice for the purposes of this thread I define fitness as the average lifetime contribution of individuals posessing a particular genotype to the population after one (or more) generations. In other words, not just the numbers of offspring that an individual can pump out, but the number of offspring carrying a particular genotype that themselves live to reproduce. So, simplistically, fitness of a genotype = (average fecundity) X (fraction surviving).
Obviously, there is a lot of detail and nuance (relative vs absolute fitness, for instance) that I'm leaving out, but that's the gist, and probably sufficient for this particular discussion.
Let me isolate his definition
So, simplistically, fitness of a genotype = (average fecundity) X (fraction surviving).
and
In other words, not just the numbers of offspring that an individual can pump out, but the number of offspring carrying a particular genotype that themselves live to reproduce.
Though it is simplistic it's a good starting point to state my objection.
For the opening post, i'll just state that this definition seems to be recursive in nature. In other words fitness is the ability to produce individuals that have the propensity to to produce individuals that have the propensity, etc.
(Fitness of a genotype)= (Average Fecundity)X(Fitness of offspring's genotypes)
The ability of the offspring to themselves produce offspring would have to be in the definition, or else we come to the absurd conclusion that producing a large number of sterile offspring is the "fit" thing to do.