Do dogs get pleasure from mating?

Animals Besides Humans that Mate for Pleasure

If an animal must mate to reproduce, the entire future of its species depends on having sex. The most obviously beneficial adaptation for such a species is, therefore, pleasurable sex. While it’s difficult to ask them if they enjoy doing the deed, a quick look at their behavior shows that, at the very least, most mammals and birds experience sexual pleasure.

The Big O

When it comes to the question of whether or not animals experience sexual pleasure, the answer is simple: most animals wouldn’t take time out for sex if it didn’t feel good. They certainly don’t choose to have sex in order to make babies as they are not capable of understanding reproduction. All mammals have the physiological capacity for orgasm because they all have a penis or clitoris, and evidence suggests they all experience it. Research with female macaques recorded muscle contractions, facial expressions and vocalizations that demonstrated they do have orgasms. Interestingly, while most male birds lack penises, the male weaver bird has a clitoris-like structure and stimulating it produces orgasm. It stands to reason that males and females of other bird species may have similar structures.

Lovers, Not Fighters

It’s a common misconception that animals only have sex in heterosexual pairs and only when the female is fertile. Bonobos were the first to prove this wrong, but when it comes to using sex for interpersonal lubrication, they’re far from the only ones who do it. Life-long, same-sex pairings are the norm for some animals, including male lions and dolphins. Both sexes of many primates, including virtually all of the monkeys, seek out males and females for sexual encounters, have sex even when they could not possibly reproduce — such as during pregnancy — and tend to resort to it to ease high-tension social situations. These tendencies show that sex serves more than just a reproductive purpose.

Group Gratification

Group flings are the in thing for mammals from monkeys to livestock. Woolly spider monkey males line up peaceably to take their turns with females who are in heat. Domesticated female cattle display their readiness to mate by mounting each other, which signals the bulls to come running. Female cats in heat, including African and Asian lions, will copulate with multiple partners up to several hundred times in one day. It is pretty tough to imagine that these reproductively unnecessary levels of contact are nothing but an odious chore.

Can’t Get There from Here

It’s easiest to make the case that animals experience sexual pleasure when they engage in activities where pregnancy can’t possibly result — as is the case with oral sex. Two male bears from a zoo in Croatia were caught engaging in oral sex — and these guys weren’t the first to the party. Oral sex is well documented in mammals as diverse as rats, fruit bats, horses, goats, dolphins, most primates, cheetahs, lions, hyenas, sheep and cattle.

Solo Players

It can’t be reproductive when you don’t have a partner, but that doesn’t stop females and males of virtually all primate, bird, rodent and livestock species, as well as deer, orcas, dolphins and the many other species who’ve been caught in the act. In fact, males of almost every domesticated and zoo mammal and bird species can be trained to masturbate into receptacles in order to collect semen for artificial insemination — with very little provocation. While in this case the ultimate intent is reproductive, the animals certainly don’t know this.

Dolphins’ complex clitorises are the key to understanding their sex lives

There’s an oft-cited factoid that dolphins are, along with humans, one of the few animals that have sex for pleasure. It’s based on scientific observations of dolphins copulating year-round even though females are only fertile for a few months of the year. But of course, because of the pesky animal-human language barrier , no one’s ever been able to actually ask a dolphin about sexual pleasure.

The structure of female dolphin reproductive anatomy, though, can speak for itself.

At the Experimental Biology conference held April 6-7 in Orlando, Florida, marine mammal researcher Dara Orbach presented preliminary findings from one of the first studies to examine bottlenose dolphin clitorises. Orbach and her co-author, Patricia Brennan, both from Mount Holyoke College in Massachusetts, were surprised to find dolphin clitorises have several bundles of nerves, similar to human clitorises. Because the clitoris is accessible during any kind of position a male would take during copulation, says Orbach, it’s highly likely it plays a role in pleasure.

Orbach and Brennan examined clitorises from 11 dolphins that had died of natural causes and washed ashore. The sample size is relatively small, but crucially, it included dolphins of all ages, from calves to adults. They looked at the clitoris anatomy as a whole, and then conducted other experiments to identify each type of tissue present in the structure. Across all ages, dolphin clitorises had erectile tissue, blood vessels, muscles, and nerve bundles. They also contained a hard, cartilage-like tissue called elastin, which Orbach says help keeps the blood flow concentrated in the erectile tissue.

Although these preliminary findings don’t definitively prove that dolphin reproduction can also be for pleasure, they do add evidence to the argument that for dolphins, sex isn’t entirely about reproduction. Sex can serve several different functions, like social learning or establishing dominant hierarchies, says Orbach. Male calves frequently mate with their mothers, and “a lot of the [dolphin] mating we see in the wild is homosexual mating,” she says. “It could be males establishing who’s the leader in the group.”

Before Orbach and Brennan submit the study to a peer-reviewed journal, they’re waiting to find a few more dolphins that died of natural causes to add to their sample size. Examining dolphins shortly after death could confirm that the cells they observed are, in fact, nerve bundles. The 11 dolphin clitorises examined so far are part of a collection of over 300 reproductive tracts of dolphins, whales, and porpoises that reside in the Mount Holyoke College necropsy facilities. These animals had beached across the US, and then been found and collected by local stranding groups and shipped to the lab.

Historically, female reproductive anatomy in animals has been widely understudied. Most animal reproduction research has been focused on the variations among penis morphology, at least partly because the penis, as an external organ, is easier to access. As scientists have started studying vaginal morphology in the past 10 years or so, it’s become clear that vaginas are equally diverse. For example, unlike human vaginas, whale, dolphin, and porpoise vaginas all have extra folding in the reproductive tract, making them unique among members of different species. Why this folding would take place is a mystery, but Orbach believes it’s not arbitrary. “If you have such diversity in structure, you’d expect it to have a function,” says Orbach.

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