Recombination mixes up genes that may be highly advantageous to a specific environment.

• Why change something that is working?
• Assumes non-random associations between alleles at different loci were selected for by previous generations.

• Asexual species contribute all resources to offspring that can later produce more offspring.

Sexual reproducing populations are susceptible to invasion by asexual individuals, all else being equal. Asexual populations can reach a greater size more quickly.

• In a hypothetical population where each female produces one offspring, the sexual population halves itself each generation (assuming a 50/50 sex ratio).