‘7 Times Longer And Wider’: Scientists Say They Found The First Mammal That Mates Without Penetration

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Samuel Spencer Contributor
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Scientists have discovered  the only known mammal in existence that mates without penetration.

The serotine bat, a common Eurasian bat, was discovered to mate without intromission, the process of inserting the penis into the vagina, according to a study published Monday in Current Biology. Scientists only recently observed this behavior due to the bat’s “nocturnal and elusive lifestyle,” the study noted.

When the male serotine bat’s penis is erect, it is “seven times longer and wider” than the female’s vagina, making intromission impossible. Instead, males have been found to use their penis as a “copulatory arm,” per the study.

This method of mating appears to be less efficient than the normal form of mammal mating, with researchers finding that bats stayed in their “copulative embrace” for up to 12 hours, according to CNN.

Instead of inserting the penis into the vagina, the male bat will use his oversized penis to push aside the female’s tail sheath, before pressing his member against her vulva, Live Science explains. (RELATED: Terrorist Beaver Seriously Damages National Landmark)

“Once the penis was firmly pushed against the vulva, the male remained still, moving only intermittently and no more vocalization was detected,” the study authors wrote. “Following copulation, the fur on the female’s abdomen appeared wet, indicating the presence of semen.”

“Further investigation should focus on the role played by pre- and post-copulatory female choice as well as male competition in the evolution of this prolonged and particular mating behaviour,” they added.