Dolphin clitorises are incredibly similar to those of humans. In a recent study, scientist Dara Orbach, a research associate at Mount Holyoke College, and Patricia Brennan, an assistant professor of biology completed autopsies on 11 dolphins who had died of natural causes.
They dissected their reproductive organs and created 3D tomography (CT) scans of their vaginas. They found that the female dolphin’s clitoris is “remarkably similar” to human women’s.
Just a like a human female the dolphin has a clitoral hood, and two areas of extensive erectile tissue that merge into a single body.
Because the way the clitoral hood is thin and folded in a manner very similar to humans the scientist think that it might engorge and swell just like humans when aroused.
A human clitoris primary function is for pleasure, so it's likely that the same goes for dolphins. However, unlike humans, the dolphin clitoris is located at the entrance to the vaginal opening rather than externally like humans.
Dolphins are well known for their sex lives. Unlike most other creatures dolphins have been observed to have sex for pleasure. The intelligent creatures have even been observed masturbating using live eels. Dolphins are also famous for playing for both teams.
Dolphins have sex for fun
It isn’t unusual for biologists to witness same-sex activities in dolphin pods with the animals stimulating each other both around their reproductive organs and even in their blowholes.
This isn't the first sex-related dolphin research Orbach has done. Previous research has also looked at the sex lives of dolphins. A study published in Experimental Biology in 2017 titled ‘An intimate look at the mechanics of dolphin sex’ examined the shape of male and female reproductive organs to see how they evolved.
Penis and vagina must co-evolve
"While it may seem intuitive that the penis fits well into the vagina during copulation, the biomechanics and details of the anatomical fit can be quite complex and have seldom been explored," said Orbach.
"Whales, dolphins and porpoises have unusual vaginal folds, spirals, and recesses that the penis and sperm must navigate through to successfully fertilize the egg."
The intimate study involved extracting the reproductive tracts from dolphins, porpoises, and seals that died naturally. The male sex organ was then inflated to full erection and inserted into the female animal's vaginas to simulate copulation.
They used tomography (CT) scans to model how deeply the penis penetrated the vagina and which anatomical landmarks are in contact.
"Most previous research on genitalia has focused on the penis," Orbach said. But understanding the female sexual organs and in particular, how the two sexes interact is an important study to better understand animal evolution.
"The techniques we have developed can be applied to other species and help advance captive breeding programs," said Orbach.
"For example, we demonstrate that particular anatomical landmarks are in contact during copulation and suggest that physical stimulation of these landmarks during artificial insemination may improve the probability of conception. Our research can also help predict which natural copulations will lead to fertilization, as males most sexually approach females at specific angles to optimize their genital alignment and penetration."