How big is too big? Bat ’s enormous penis makes penetration impossible

If you go out walking at dusk nearly anywhere in Europe or Asia, you’re likely to catch a glimpse of a serotine bat ( Eptesicus serotinus ) in flight. These furry creatures are a familiar sight, known to roost in chimneys and in the gables of old churches. But although serotine bats are quite common, scientists have yet to unravel all their mysteries. In fact, up until recently, the male of this species was hiding a truly astonishing secret: a penis so large that it makes “traditional” sex impossible. “People have always wondered why bats have such large penises,” says Brock Fenton, a biologist at the University of Western Ontario who’s been studying the animals since the 1970s. Even then, he and his fellow researchers pondered whether such oversize members might pose a problem for penetration. “The penis is too big. The vagina is too small. How does it work?” According to a study published today in Current Biology , at least in the case of serotine bats, it doesn’t . Instead of mating via penetrative sex, the authors report, these bats engage in contact mating, in which sperm is transferred simply by rubbing the genitalia together, a behavior never before documented in mammals. Fenton, who wasn’t involved in the research, says the finding represents an important contribution to the “fascinating topic” of bat reproduction. When it comes to sex, bats have always been full of surprises. Some mate hanging up...
Source: Science of Aging Knowledge Environment - Category: Geriatrics Source Type: research