Groundbreaking Research Unveils First Evidence of Non-Penetrative Mating in Mammals

A recent study published in Current Biology has unveiled a unique mating behavior in mammals – specifically in the serotine bat. The penises of bats are about seven times longer than the vaginas of their partners, making penetration impossible. Instead of using their genitals for penetration, male bats use their oversized penises to move the female’s tail sheath away and maintain contact mating.

Nicolas Fasel, from the University of Lausanne, Switzerland, and lead author of the study stated, “We think that perhaps it is like in the dog, in which the penis becomes engorged so that it becomes stuck, or perhaps they simply could not insert it, but that type of copulation had not been described in mammals until now.”

The researchers observed the genitals during copulation using images from cameras placed behind a grate that they could climb onto. They analyzed a total of 97 pairings from the Dutch church and the Ukrainian center. They also observed that the female’s abdomen appeared moist after copulation, suggesting the presence of semen. However, more studies are needed to confirm that sperm was transferred.

The researchers also characterized the morphology of the genitalia of serotine bats by measuring the erect penises of live specimens and performing necropsies on those that died. When erect, the penises of serotine bats are about seven times longer and seven times wider than the vaginas of females of