Snakes have heart-shaped clitorises, a new study has found. An international team of researchers, led by the University of Adelaide, have provided the first anatomical description of this reproductive organ in serpents. The study was recently published in the Proceedings of the Royal Society B Journal.
The researchers analysed female genitalia in adult snake specimens across nine species, as part of the study. They also compared the female snake genitalia to adult and juvenile male snake genitalia.
Since female genitalia are "conspicuously overlooked" in comparison to their male counterparts, there is limited academic understanding of sexual reproduction across vertebrates such as snakes and lizards, a statement released by La Trobe University in Melbourne said.
Which snake species were studied?
The snake species studied were Acanthophis antarcticus, also known as the Death adder, Pseudonaja ingrami, a serpent native to different parts of Australia, Morelia spilota, a snake native to Australia, New Guinea, Bismarck Archipelago, and the northern Solomon Islands, Pseudechis colleti, Pseudechis weigeli, Bitis arietans, a snake species native to semi-arid regions of Africa and Arabia, Lampropeltis abnormal, a serpent species from Los Brisas del Mogoton, Nicaragua, the Agkistrodon bilineatus, a snake species native to Mexico and Central America, and Helicops polylepis, a species from Estación Biológica Madre Selva, Peru.
In a statement released by University of Adelaide, Megan Folwell, who led the research, said across the animal kingdom, female genitalia are overlooked in comparison to their male counterparts, and the new study counters the long-standing assumption that the clitoris is either absent or non-functional in snakes.
More about female snake clitorises
Kate Sanders, another author on the paper, said the researchers found the heart-shaped snake clitorises, or hemiclitores, are composed of nerves and red blood cells consistent with erectile tissue. This suggests that the clitoris may swell and become stimulated during mating. She added that this is important because snake mating is often thought to involve coercion of the female, and not seduction. In other words, it is often believed that female snakes are coerced or forced into mating.
In the statement released by La Trobe University, study co-author Jenna Crowe-Riddell said the anatomy of female snake clitorises can flip the coercion assumption.
The researchers found the hemiclitores on snakes using bio-imaging techniques and dissection.
Sanders also said that through the research, the authors have developed proper anatomical descriptions and labels of the female snake genitalia, and they can apply their findings to further understand reproductive evolution and ecology across snake-like reptiles, such as lizards.
Folwell hinted at the fact that the research tries to overcome the taboo associated with female genitalia across every species.