Addressing his professional colleagues in the preface to the first edition of his Psychopathia Sexualis in 1886, the sober and unflinching Richard von Krafft-Ebing assured them he understood his duty to ward off the idly curious public. “A scientific title has been chosen,” he wrote, “and technical terms are used throughout the book in order to exclude the lay reader. For the same reason certain portions are written in Latin.” The translator of its 12th edition did not heed this due diligence. The case histories are all in English, and the “technical terms” Krafft-Ebing coined, such as “masochism,” would soon come into common usage.
Or perhaps they already were: it’s not clear when the translation appeared, though the scanned copy available at the Internet Archive looks  like something printed in the 1920s or ‘30s. The paperback copy of Psychopathia that I found at a garage sale as a teenager (back in the pre-online, Betamax-era dawn of civilization) was a cruddy reprint of that edition, likely pirated in the early 1960s by somebody cashing in on the loosening of obscenity standards.
Krafft-Ebing would have been aghast to think of a wide-eyed adolescent reading his evidence that the limits of the human libido reach all the way to the limits of the human imagination -- if anything, a little beyond them. Kids these days have probably witnessed everything the Victorian-era sexologist describes on video by the age of 13, but the book sure did boggle my mind.
Time jades you. Sitting down to read John A. Long’s popular science book The Dawn of the Deed: The Prehistoric Origins of Sex (University of Chicago ), I felt immune to the kind of astonishment that Krafft-Ebing elicited in me ages ago. The cover – which should win a prize, by the way -- shows two fossilized dinosaurs in flagrante delicto, with a black censorship bar to keep things within the bounds of decency. Part of the humor, of course, is that the mentality that would be shocked by the scene is practically as extinct as the dinosaurs themselves.
It’s an astonishing book, even so. And in a couple of ways.
The author -- who serves as vice-president of research and collections at the Natural History Museum of Los Angeles County -- devotes roughly a third of the space to recounting how he and his colleagues at the Melbourne Museum identified the earliest known fossilized embryos of a vertebrate – discovered, complete with umbilical cord, in fish from 380 million years ago. Besides its age, the fossil revealed that the mother had been carrying her fertilized eggs, rather than just depositing them in a safe place.
The team announced its findings in a paper that ran in the journal Nature in 2008. It so happened that this roughly coincided with Queen Elizabeth's visit for the opening of its Royal Institution of Australia (described on its website as a “national science hub” for research and education). A computer-animated clip  showing the prehistoric mother and child ran during the festivities, and Long spent a couple of sleep-deprived days answering questions from reporters around the world. Someone later calculated that the discovery netted “around $2 million worth of media coverage,” and within a week of announcing the fish’s scientific name, Materpiscis, a Google search found it appearing on almost 50,000 sites around the world.
The media frenzy sounds grueling, but it’s much less interesting to read about than Long’s account of subdued excitement in the laboratory, as the researchers figured out what they were seeing under the microscope. It was, Long explains, “the first known case for fishes, our distant ancestors, that involved the male copulating with the female rather than spawning in water like almost all fishes today do.” Long suggests that this intimate moment occurred on the ocean floor; and, given structure of the partners’ genitalia, the female was probably on her back as the male mounted her. (The missionary position has never seemed as old-fashioned as it does just now.)
Another paper in Nature from 1998 by a different group of Australian scientists determined that the earliest evidence of sexual reproduction of any sort can now be dated to somewhere between 1.68 and 1.78 billion years ago. Mind-bending as the temporal scale here may be, Long’s survey of the evolutionary history of sex is accessible and absorbing, and could be adapted for the screen easily enough. Which, given the rise of creationist museums, would probably be a good idea
But if it were, much of the audience would be shocked. Nothing prepares you for learning just how polymorphously perverse nature really is. Despite the enormous differences between Long’s book and Psychopathia Sexualis, they are both catalogs of behavior at its most extreme.
That doesn't mean gay penguins, either. A few years back, the heteronormative propaganda of March of the Penguins was undermined by news that Silo and Roy, two male penguins at the Central Park Zoo, were raising a chick together  – with similar arrangements emerging at other zoos around the world.  This is not shocking. Same-sex erotic activity has been reported in about 450 species.
No, what we're talking about here is animal behavior that wouldn’t be appropriate to mention in a diversity training video: Female porcupines seen using a stick as a dildo, masses of grunions (a kind of fish) having regular orgies on the beach in California, and male bedbugs that impregnate by stabbing the female’s abdomen and ejaculating in the wound.
Once the glans of their partner’s penis has been inserted, female Chinese fruit bats perform the impressive feat of bending down to lick the exposed portions of his genitalia. This is the first known case of a non-human mammal “practicing [fellatio] as part of the stimulation leading to mating,” notes Long, “more or less as foreplay.” The Chinese scientists who reported the behavior indicate that “mating pairs spent significantly more time in copulation” when the female performed this acrobatic maneuver, as one may well believe.
The pages on necrophilia in Psychopathia Sexualis were, as I recall, particularly disturbing. Long points out that snakes and tortoises have been known to commit it – presumably as a result of confusion, rather than by preference. And there’s a kind of spider the very name of which recalls one of the technical terms Krafft-Ebing introduced: the Harpactea sadistica. The male has “needle-like structures” used “to stab the female and deposit his sperm directly into her ovary, eliminating the need for any courtship niceties.”
Well, all sorts of bizarre stuff is bound to emerge in the course of 1.7 billion years. Every kink its own genome. But the really strange thought is that most of this behavior must have proven its worth in the struggle to survive. Not the necrophilia, let’s hope. But who knows? After reading The Dawn of the Deed, it’s hard to think of anything as an unnatural act.