Scientists have discovered that female snakes have a clitoris — a previously overlooked or dismissed part of their anatomy (and that of many other animals), according to a new study.

“It’s quite a taboo area. Female genitalia is not an easy subject to bring up sometimes and I think people were happy saying ‘it doesn’t exist. There’s no need for snake to have one,’” said lead study author Megan Folwell, a doctoral student at the University of Adelaide in Australia.

Folwell decided to investigate the female genitalia of snakes after noticing that very little research had been done on the topic. She found the organ varied among the types of snakes, taking up most of the anterior tail region in some, according to the study published Wednesday in Proceedings of the Royal Society B.

“People weren’t looking, and it was hard to find. It’s not the easiest structure to see in some (snake) species,” she explained, adding that some researchers had previously confused the clitorises in snakes for scent glands.

This work has definitively cleared up the question of whether the clitoris exists in snakes and also offers some context on what purpose it potentially serves, said Kurt Schwenk, professor of ecology and evolutionary biology at the University of Connecticut. Schwenk was not involved in the research.

The role of female genitalia

In conducting the research, Folwell carefully dissected the genitalia of nine different species, including the common death adder, that represented four main snake families, Elapid, Viperid, Pythonidae and Colubridae. She found the sexual organ in all the snakes she examined in the study.

Officially known as a hemiclitoris because it has two distinct parts, the organ appeared to be shaped “like two teardrops that formed a love heart structure” in the death adder, Folwell said. In reptiles like snakes, the penis is known as a hemipenis because it also has a dual structure.

Folwell said that further work was needed to reveal exactly why snakes had a clitoris, but according to the study, a cluster of nerve endings in the hemiclitoris suggested it played a role in sexual arousal, perhaps creating a “sensation to the female snake during courtship and copulation, which might promote longer and more frequent mating leading to increased fertilization success.”

It could also give the female snake information to decide whether she wants to cut the copulation short to reduce chances of reproducing with a particular male, Schwenk said.

“It empowers the female to make decisions that allow her to control the copulation and which male she copulates with,” Schwenk said.

“There’s been a tendency historically to see females of other species, well not just other species, as passive recipients of male copulatory behavior or even victims.”

But research like this shows that female animals likely have a much more active part in mating than they are given credit for, he added.

Studies of female genitalia in the animal kingdom are relatively sparse because of an “overwhelming focus on male genitalia,” according to the study.

It is important not to project human traits on different species, but it is impossible to completely divorce the sociopolitical climate from the way scientists conduct their research, Schwenk said. Through both bias and what is easiest to observe, most of the questions of biological research have been focused on male anatomy and behavior.

Some female biologists are seeking to redress this imbalance. Last year, Patricia Brennan, an associate professor of biological sciences at Mount Holyoke College and coauthor on the new snake study, revealed dolphins also have functional clitoris.