Jason G. Goldman highlights just a few, reassuring humans that “for just about any fantasy between consenting adults that might be thought of as beyond conventional sexual practices or decency as dictated by society, you can bet that there’s a non-human species for whom that particular behaviour is commonplace”:
Take giraffes, for instance. Males, called bulls, make casual visits to various groups over time in search of a cow who might mate with him. In order to select the mating partner the bull literally finds the one that best suits his taste – by sampling their urine. Females co-operate in this “urine-testing” ritual, according to researchers David M. Pratt and Virginia H. Anderson. “When the bull nuzzles her rump, she must produce a stream of urine if he is to catch some in his mouth and savour it,” they write. If a cow is particularly attracted to a visiting bull, she may simply decide to urinate as he walks past her, no prodding required. Urolagnia, or “golden showers” as it is more commonly known, is not a human invention, it seems.
On a related note, Christopher Ryan recently delivered a not-yet released TED talk on human sexuality and its animal origins. Ben Lillie recaps:
Where did our misconceptions about sex come from? Well, Darwin, as it turns out, was a world-class Victorian prude. He was fascinated by the colorful genital swelling in bonobos, but what he didn’t know is that female chimps have sex 1-4 times an hour with up to a dozen partners.
Furthermore, Ryan notes that female chimps are sexually available for 40% of their menstrual cycles, but bonobos for 90% — almost as much as humans, who are capable of engaging in sex at any point in their cycle. That is a trait that is vanishingly rare among mammals.
For Ryan, a key question to understanding the origin of human sexuality is, “Are human beings a species that evolved in the context of sperm competition?” Are they competing against each other or with the sperm of other men as well? It doesn’t seem to be the case. For example, the average human has sex about a thousand times per birth. “If that seems high to you,” laughs Ryan, “don’t worry, it seems low to other people in the audience.” A more typical number among apes is to have sex about a dozen times per birth. Additionally, Ryan notes, humans and bonobos are among the only animals that have sex face to face. They also have external testicles. Says Ryan, ”External testicles are like having an extra fridge in the garage for beer. If you’re the kind of guy that has a beer fridge, you expect a party to happen at any moment.”