#1 - Posted: 09/08/2008 18:16
The reason given in my college classes for sex was that sex yields more genetic diversity and variation within a species. And diversity and variation are the key to survival of the speices in a ever changing and hostile world. One example would be If pedators could evolve quicker then their prey through sexual varition, the predators would be able to evolve to overcome the prey's defenses. And once that happened, the prey would vanish as a species because they could not evolve quickly enough through variation caused by mutations to keep up with the predator's evolutionary changes. Survivial of the species as a whole is key to survival of the individual gene. Also a single gene's survival chances are better if "it's offspring" are varied individuals, rather than all the same. Once again, variation is the key to survival given varying environmental stresses on a population.
Plus, sex is a hell of a lot more fun.