Want Better Breeding? Do It With A Partner.

In the grand debate over breeding best practices, scientists now have substantial proof that sexual reproduction is superior to asexual reproduction…that is, if you’re a plant. In a study recently published in Molecular Biology and Evolution, evolutionary geneticist Jesse Hollister along with a team of researchers demonstrated that sexually reproducing species were healthier over time, as they don’t amass harmful genetic mutations like asexual procreators do.

Yellow evening primroses. Photo by Matt H. Wade.

Hollister and his colleagues experimented with numerous evening primrose species, a flower chosen due to the fact that approximately 30 percent of the species had developed to breed asexually, pitting 30 pairs of primroses against one another, each pair containing a flower that fell in either reproductive camp. By comparing the offspring produced, Hollister said they verified that asexual reproduction led to an accumulation of “deleterious mutations over time,” in a process called Muller’s Ratchet, by which “the species’ average fitness is reduced and they are less able to compete in the ecological arena than sexual species, so they have an increased probability of extinction.”

According to Phys.org, evolutionary biologists were apparently puzzled by the inclination to reproduce sexually, pointing out that asexual reproduction seemed more rational, mathematically speaking, as every organism would be able to bear offspring, rather than only half of the population. What they had failed to consider, though, was that since mutations naturally occur in every new generation. Asexually reproducing species, if they harbored harmful mutations, would simply be passing on those defects to their offspring since their reproduction process was, essentially, cloning itself. In contrast, offspring produced sexually bore a mixture of the parents’ genes, without all of the mutations passed down in addition to the naturally occurring ones.

Professor Marc Johnson, part of the study’s research team, remarked that the findings were “the first solid genetic support” for the Muller’s Ratchet theory, going on to say: “This study has allowed us to unlock part of the mystery of why sex is so common: it's good for your health, at least if you are a plant.”

We hear there’s a pretty good case for humans as well.