Fitness: Hueristic or Fundamental to Biology?

If "fitness" is an issue for some then maybe drop the term in favor of "success." This is a pretty good defenition. Reproductive success in a single generation seems "fit" to me. Whether the genotype/phenotype of the offspring can also be classified as "fit" remains to be seen.Edited by AZPaul3, : Minor boo-boo's

I am having a hard time understanding the question. “Fit” means coming up on the positive side of Natural Selection, doesn’t it? If a specific phenotype or gene (and whether we count one or multiple generations of them in the definition) does not survive its environment to reproduce, does not survive the selective pressures, isn’t this denoted as “unfit?”I cannot see “fitness” and Natural Selection being separate things. One is not a “fundamental concept” of the other. As far as fundamental concepts, Natural Selection is a fundamental concept (a separate operative mechanism) of Evolution. The same relationship does not exist between Natural Selection and “fitness.” Being “fit” is not a mechanism working within the paradigm of Natural Selection, it is nothing more than shorthand to denote success. Survival of the successful, anyone?And, IMHO it matters not from what view we look. In an organism-based view “fit” denotes surviving to reproduce (one generation, two generations, 2000 generations, take your pick). In the gene-based view “fit” denotes being passed into other generations (1, 2, 2000, whatever).Are we starting down the road of Semantical Quibbles? Isn’t the real question not “is fitness a concept within NS,” but, “how do we define success (fitness)in NS?”Now we can quibble the number of offspring vs number of generations vs percentage of available alleles vs number of copies of genes...you know...the good stuff.