In her 20 years as a genital morphologist, Patricia Brennan has checked out a number of animal clitorises. She’s seen feminine lizards’ two spike-studded protrusions, that are nearly equivalent to their counterparts on males. She’s glimpsed the outstanding appendage by means of which feminine noticed hyenas urinate and provides delivery. She’s even studied the thin-skinned, nerve-laced organ of a feminine dolphin, which Brennan’s work suggests makes intercourse pleasurable. But till fairly lately, she had by no means discovered a clitoris on a snake.
Brennan, to be clear, had checked. A researcher at Mount Holyoke College, she had dissected all types of snakes and lizards through the years and at all times discovered the identical factor: Males sport a pair of closely ornamented penises, known as hemipenes, that may, like the liner of a pocket, be popped out of the bottom of the tail; the identical trick works on many lizard females, whose clitorises, or hemiclitores, can be flipped out. But each time Brennan tried the maneuver on a girl snake, she turned up zip, nada, zilch. Eventually, Brennan, like many others in her discipline, concluded that snake clitorises should not exist.
So when her collaborator Megan Folwell, of the University of Adelaide, reached out final 12 months to share photographs from a latest dissection of a feminine death-adder tail, “I almost fell off my chair,” Brennan instructed me. What Folwell had discovered was unmistakable: There, proper under the venomous snake’s cloaca (an all-purpose, vagina-like orifice), nestled between a pair of scent glands, have been two small, pink protrusions—a pair of clitorises that had by no means been absolutely documented earlier than. Folwell, Brennan, and their colleagues went on to seek out related buildings throughout a spread of species, and so they have now printed the primary full and definitive description of snake clitorises—a discovering that would rewrite the narrative of reptilian intercourse.
The discovery is each shocking and never. The buildings are small, fragile, and simply to break or overlook; Sara Ruane, the assistant curator of herpetology on the Field Museum, in Chicago, says that studying about Folwell’s work was “the first time I have ever even thought about” snake penises having a feminine analog. Multiply that sentiment numerous occasions over, and maybe it explains how researchers principally missed a complete organ, in a complete group of hundreds of animals, till now. But evolutionarily talking, there’s no motive snakes shouldn’t have clitorises, which come up from the identical knot of cells that provides rise to penises. In addition to lizards, snakes’ closest kinfolk, different teams of reptiles have clitorises, as do mammals.
Snake clitorises made cameos in some earlier research, however Folwell and her colleagues argue that lots of them have been misidentifications of hemipenes or scent glands. (After I wrote to a number of of those researchers, two—Oliver Hawlitschek and Stefano Rizzi—bought again to me and largely stood by their work, though Hawlitschek famous by e mail that he would “not exclude that we may have mis-sexed some samples.”) Either method, these varieties of errors is likely to be extra avoidable now that researchers have a sharper set of instruments with which to find out a person snake’s intercourse. Traditionally, when sexing a snake, “you cut a tail open and look for hemipenes,” Ruane instructed me. “If they’re there, it’s a boy. If they’re not, you assume it’s a female.” But Folwell’s work, Ruane stated, convincingly reveals that the absence of hemipenes isn’t the one factor that defines a girl snake. Clitorises are very a lot current.
What’s not completely clear but is what snake clitorises do. Based on what researchers find out about mammalian clitorises, the buildings might, when stimulated, make a feminine snake extra receptive to intercourse by, say, lubricating or stress-free her cloaca. The potential is there: Folwell and her colleagues discovered that snake clitorises comprise a tapestry of blood vessels and nerve endings, hinting that the organs can engorge and really feel.
Snake courtship is “quite tactile,” says Jenna Crowe-Riddell, Folwell’s adviser on the University of Adelaide. During their equal of foreplay, the reptiles will coil their tails round one another, the male vibrating and undulating; he’ll typically rub his chin up and down the feminine’s physique or flick at her together with his tongue. Some of those behaviors might have interaction the clitorises, making the feminine extra wanting to mate or prolonging the coupling occasion. In sure snake species, a feminine can retailer sperm from a number of companions in specialised organs for years, and it’s potential an particularly stimulating sexual encounter could lead on her to attract from a selected associate’s sperm for a number of clutches of offspring. (How feminine snakes would possibly truly choose sperm, nevertheless, isn’t properly understood.)
None of that has but been proved, although, and analysis in different reptiles hasn’t been a lot assist. One paper from the Nineteen Nineties steered that lizard clitorises “were there just to stimulate the male,” Brennan instructed me. “We were like, Okay, I really doubt that that’s what’s happening.” Whether feminine snakes get pleasure out of all that is one other query. The specialists I spoke with have been on board with the concept, however it’s difficult to check. Snake faces aren’t essentially the most expressive—though Crowe-Riddell does have some concepts about an experiment involving numbing cream.
In normal, scientific analysis into feminine genitals is “not always the easiest topic to get funding for,” Folwell instructed me. Maybe that’s partially pushed by the truth that “it’s practically easier to investigate something that is protruding rather than something that is inside,” says Malin Ah-King, an evolutionary biologist and gender researcher at Stockholm University. Cultural biases have raised roadblocks too. Many scientists have traditionally presumed that females are merely passive receptacles for sperm. Centuries in the past, Darwin posited that the evolution of animal intercourse relies upon “on a struggle between males for possession of the females”; even some trendy scientists have proposed that feminine fauna, in contrast to males, would possibly lack the psychological capability to actively select their mates.
And when pleasure-related organs similar to clitorises get entangled, there might be downright squeamishness. “We don’t have a problem with male orgasm, because it’s associated with the transmission of sperm,” says Mariella Herberstein, a behavioral ecologist at Macquarie University. But scientists can’t say the identical for feminine pleasure, and the taboo round clitorises has caught.
Hang-ups similar to these hold the scientific concentrate on males, skewing how people interpret animal intercourse lives. Belatedly finding out feminine genitalia “is a recurring pattern” in biology, Ah-King, who has written on the male-centric bias within the examine of animal intercourse, instructed me. Scientists spent years considering that male earwigs use their genitals to effectively dislodge the sperm of different suitors from the feminine’s physique—solely to later uncover that a lot of her sperm storage organ is out of his attain. Early work into duck mating steered that males forcibly propelled their corkscrew-shaped penis deep into females who had little alternative within the matter—till the mid-aughts, when Brennan discovered that duck vaginas can redirect undesirable mates into genital dead-ends.
Snake penises, which come adorned with all types of spines, hooks, depressions, flounces, and frills, have been properly studied since not less than the 1850s, Folwell instructed me, far predating devoted inquiries into their feminine parallels. That is likely to be a part of why scientists have lengthy conceived of snake copulation as a male-driven endeavor, with bachelors duking it out for entry to females that should then endure intercourse, Crowe-Riddell instructed me. Now that the science on clitorises is catching up, she wonders, “Could seduction be a part of it?” Better understanding of snake clitorises might additionally support different scientific endeavors. If serpentine clitorises are as various as their penises, researchers might have one other software for distinguishing between species, says Leticia Afuang, a herpetologist on the University of the Philippines at Los Baños.
With their lack of fur, heat blood, and limbs, snakes aren’t very similar to us; their sometimes-venomous bites and muscled, tubular our bodies are inclined to wig folks out. But snakes are a vital a part of many ecosystems. Their venoms have led to medicines, and their urge for food helps with pest management. They even have one thing to show us about intercourse: In the identical method that snakes are usually not simply lizards with out legs, females are usually not simply males with out penises. Perhaps higher acquainting ourselves with an oft-maligned physique half on an oft-maligned animal might immediate us to reckon with the methods by which we draw boundaries within the pure world—and encourage us to explain life not simply by what it lacks, however what it has to supply.