Without sexual reproduction, you are limited to cloning + random mutation at each generation to generate diversity. This generates fast-growing, homogeneous populations which get wiped out as a group when circumstances change to no longer favor them.
Sexual reproduction lets you grab non-harmful mutations from another genetic lineage en masse at each and every generation. This means that when circumstances change you are far more likely to have at least one offspring which can adapt to the new situation.
Because it can take hundreds of generations for helpful mutations to appear, and changing circumstances can wipe out an entire homotype, the advantages of preserving genetic diversity outweigh the costs.
aha, thank you. The compared to alternatives would be cloning, no change, or small and slow perturbations. Sexual reproduction === intentional mass mutations, that's such a clear way to conceive of it all. It's the genes that matter here at the end of the day. Wow
Sexual reproduction lets you grab non-harmful mutations from another genetic lineage en masse at each and every generation. This means that when circumstances change you are far more likely to have at least one offspring which can adapt to the new situation.
Because it can take hundreds of generations for helpful mutations to appear, and changing circumstances can wipe out an entire homotype, the advantages of preserving genetic diversity outweigh the costs.