.Over 100 species of insects engage in same-sex mating (in some species, it's even more common than heterosexual mating). Scientists have been speculating about why they might what leads to the puzzling behavior, which takes time and energy, exposes the insects to potential disease to injury, and offer no benefits as far as creating offspring. Are they mating as a form of social dominance, a practice behavior, or expressing a sexual preference?
According to a new study from researchers at School of Biological Sciences in the , at least in the case of beetles, the answer may be none of the above: beetles are simply inept at mating.
When there was less pressure to find the right mate, beetles = made more mistakes, mating indiscriminately. In male-heavy populations with higher stakes, however, same sex-pairings were far less common. The team bred six populations of red flour beetles, and watched them for 80 to 100 generations in male-biased and female-biased groups. Though the amount of sexual activity ended up similar in both groups, in male-heavy groups, the male beetles were much more selective, more likely to mount female beetles first, and spend longer with her. In the female-heavy population, male beetles selected mates seemingly at random, disregarding the sex.
But while the discovery may shake up the world of insect sexuality, according to researcher Kris Sales, who worked on the study, the findings can't be applied to other species. “These results cannot be generalized to explain the behaviors of animals with more complex cognitive function and social structures like birds and mammals, which are likely to have very different reasons for same sex mating,” Sales told .