S ex is a tricky business, evolutionarily speaking. One problem is that sexually reproducing organisms must suffer the considerable faff of securing a mate (for the males of some species, the struggle to do so can be fatal). Another is that the mixing of two genomes into one offspring means that, per child, each parent gets only half its genes into the next generation rather than the full complement.
从进化上讲，ex是一项棘手的生意。一个问题是，性生殖生物必须遭受确保伴侣的相当大的影响（对于某些物种的男性，这样做的斗争可能是致命的）。另一个是将两个基因组混合到一个后代意味着，每个父母的基因只有一半的基因进入下一代，而不是全部补体。
