Dolphins are highly social. They have sex for social reasons as well as reproduction.
Scientists have known that dolphin vaginas contained inner flaps and folds for a long time. They also have a clitoris in the vagina in a spot that would make stimulation during copulation likely.
A new study reported that dolphin females- like humans- have a working clitoris. The findings are based on the discovery that the clitoris-like structure positioned in the vaginal entrance of bottlenose dolphins has lots of sensory nerves and erectile bodies.
In this study, scientists closely observed the dolphin clitoris from 11 females who died naturally. They studied them for the presence, shape, and configuration of erectile bodies. Later, they examined how nerve fibers ran through the tissues.
Patricia Brennan, an assistant professor of biological sciences at Mount Holyoke College in Massachusetts, said, “Just like the human clitoris, the dolphin clitoris has large areas of erectile tissue that fill up with blood.”
“The erectile tissue shape changes as animals become adults, suggesting that it acquires a functional role.”
The clitoris body was found to have large nerves. Plus, it has many free nerve endings right underneath the skin, which is much thinner than in the adjacent skin.
Scientists also found genital corpuscles much like those previously described in the human clitoris and penis tip. The genital corpuscles are involved in the pleasure response.
Brennan says, “Overall, the erectile bodies in dolphins are “surprisingly similar” to the shape of the erectile bodies in humans.”
“Since the entire pelvis of dolphins is so different to humans, it was surprising to see how similar the shapes were. Also, the size of the nerves in the clitoris body was very surprising. Some were larger than half a millimeter in diameter.”
“They got curious about the dolphin clitoris while studying the evolution of vaginas in dolphins.”
“Every time we dissected a vagina, we would see this very large clitoris, and we were curious whether anyone had examined it in detail to see if it worked like a human clitoris. We knew that dolphins have sex not just to reproduce but also to solidify social bonds, so it seemed likely that the clitoris could be functional.”
“Studying and understanding sexual behaviors in nature is a fundamental part of understanding the animal experience and may even have important medical applications in the future.”
Scientists will continue to examine the clitoris and genitalia of dolphins and many other vertebrates to help fill in these gaps.
- Patrica L. R. Brennan et al. Evidence of a functional clitoris in dolphins. DOI: 10.1016/j.cub.2021.11.020