Sexual cannibalism has been seen, though rarely, in octopuses as well. It may only occur when females die shortly after mating, scientists say, or when males are dangerously short of food. Researchers aren’t quite sure why male isopod sometimes eat females - they did just go to the trouble of creating offspring with them, after all. Both males and females have been seen eating their mates after sex. Isopods, a kind of crustacean, also engage in sexual cannibalism, though in their case it appears to go both ways. Like many species where sexual cannibalism occurs, female anacondas are much bigger than males, making it easier for them to overpower their mates. Biologists have documented female anacondas strangling their mates after mating, likely to use as food later. It’s not just spiders that eat their mates after sex. Less impressive male wolf spiders, for example, were more likely to be eaten by the females, one study found. The unfortunate males in this case may simply be in the way.Ī different theory for sexual cannibalism holds that it’s the result of females being choosy. Females that are more aggressive when hunting tend to get more food, and have better odds of surviving and having children. It’s borne out by studies showing that aggressive females are more likely to eat males. One theory posits that sexual cannibalism is what scientists call a “maladaptive side effect” of female aggression. In many species, the females behave in a manner that’s much more predatory. Over time, females that ate their mates had more children and the behavior spread through evolutionary selection. For example, a study in spiders found females that ate males had larger brood sizes than those that didn’t. Expectant mothers need lots of food to sustain their children, and the males offered a nearby source of protein. In many cases, scientists believe sexual cannibalism arose from basic necessity. The gymnastic performance is deadly, but also effective: Males that sacrifice themselves have twice as many children. The female will consume her mate, using his body as sustenance for her children.Įven more impressive, male redback spiders perform what scientists describe as a somersault directly into the mouths of females after mating. During mating, a male will place its abdomen near the fangs of the soon-to-be mother of its children. It’s also true for male brown widow spiders, who offer themselves as living sacrifices to females. Many plant species die after reproducing, as well as animals like salmon and male antechinus. That’s certainly not true for every species (humans, for example) but it does bear out for what biologists call semelparous animals - those that die after mating. From this perspective, the bodies we inhabit might be no more than vessels for the genetic information they contain once those genes have been promulgated to the next generation, the physical body has little use. Richard Dawkins’ 1976 book, The Selfish Gene, popularized the idea that the sole purpose of biological life forms is to pass their DNA from one generation to the next. Either way, it’s true what they say: It’s a mate-eat-mate world out there. Gifts of food suffice for some species, while some quick silk-lassoing is required in others. Males of some species even go so far as to offer themselves as a meal to females after they’ve finished mating.īut other clever males have devised means of avoiding becoming a post-coital meal. In many cases, there’s a chilling, calculated logic to the decision: Males are simply a good source of food for expectant mothers. Scientists have come up with a number of hypotheses for why sexual cannibalism occurs, positing that males make good meals, or that aggressive females get confused about what is prey and what isn't. Sexual cannibalism may occur in the species only rarely. Spiders, too, and it’s what gave black widow spiders their common name - though The most commonly-known example might be praying mantises, where females often bite the heads of their paramours off after mating. Yes, we’re talking about sexual cannibalism, the gruesome, surprisingly-common practice of eating your mate after procreation.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |