Reproduction without sex is more common than scientists thought

Sex 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.The fact that it is nonetheless widespread suggests that sex must have big advantages, too. One concerns genetic variety. In asexually reproducing species, the only source of variation is mutation. Sex, by contrast, produces genetically unique individuals every time. That may increase the chance that at least some survive a disease, or a change in environmental conditions, that prematurely kills the others.