DEleven are surprisingly similar to humans, the mammals are social and intelligent, they recognize each other in the mirror and call each other by name. And there is one more characteristic that humans and dolphins have in common: They have sex for fun, or at least not just for procreation. In fact, female dolphins also seem to have pleasure, as a recent study suggests.
It was already known from observations at sea that dolphins have sexual intercourse all year round in order to strengthen social bonds. During the marine animal comedy, it was also noticed that the clitoris of female dolphins is located at a point in the vagina that is favorable for stimulation. A group of biologists had aroused curiosity about the behavior of female bottlenose dolphins, who rubbed each other’s clitoris with their snouts, caudal fins and pectoral fins known as “flippers”. Such sensual stimulation also takes place between same-sex dolphins.
The team led by the biologist Patricia Brennan from Mount Holyoke College in Massachusetts examined this area anatomically. To do this, they dissected eleven bottlenose dolphins, who had died naturally, and examined their vulvar tissue under a microscope. As the scientists in Current Biology write, it turned out that female dolphins have a functional clitoris, the erectile tissue at the vaginal entrance is therefore provided with a large number of sensitive nerve endings. Some nerves were more than half a millimeter in circumference. “The dolphin clitoris has a large area of erectile tissue that can fill with blood, just like the human clitoris,” explains Brennan.
The scientists were particularly impressed by the size of the clitoris, as was noticeable when the animals were dissected. Brennan says, “We knew that dolphins not only have sex for reproductive purposes, but also for social cohesion, so it seemed likely that the clitoris could be functional.” That is why it was believed that it had to serve a purpose because female dolphins’ erectile tissues change when they reach adulthood. The cluster of nerve cells and free nerve endings on the dolphin’s clitoris is also located directly below the surface of the skin, as the researchers found. The skin on the clitoris is particularly thin, unlike on layers of skin further away from the sex organ, where the animals are less sensitive.
In the tissue samples from the dolphin’s clitoris, Brennan’s team also found so-called frizzy bodies: mechanoreceptors that react to changes in speed and vibrations and occur both in the human clitoris and in the tip of the penis, the glans. Their exact function, however, is still unclear. That fits into the insufficient picture, believes Brennan, because whether human or dolphin, female sexuality is underrepresented in science.