The Penis Poster That Rubbed People the Wrong Way

In the late 1980s, an ad selling a poster of the “Penises of the Animal Kingdom” started appearing in magazines. It promised to educate, but where did it come from?

At the tail end of the Reagan administration, strange classified ads began appearing in the backs of national magazines such as Harper’s, Mother Jones, and Spy. The ads were for a poster you could buy for $8.95, plus $2 shipping and handling—“a lithograph of rare quality suitable for framing and display.” The copy promised that the poster would “provide many hours of fascination and enjoyment,” whether it was used “as an education resource, a decoration for home or office, or a unique gift.” Sold by Scientific Novelty Co., of Bloomington, Indiana, the poster depicted the relative lengths and girths of a dozen different animal penises.

“Penises of the Animal Kingdom” was the masterwork of a man named Jim Knowlton, and his poster offered exactly what its title promised: a dozen hand-drawn penises, with the names of the animals they belonged to and arranged by size, from largest penis to smallest—sperm whale, elephant, giraffe, bull, horse, pig, porpoise, ram, goat, hyena, dog, and, finally, human. (The lengths were drawn to scale, which suggests that the specimen chosen for the dog penis was from a relatively large breed.)

Sold by Scientific Novelty Co., of Bloomington, Indiana, the poster depicted the relative lengths and girths of a dozen different animal penises.

Per its ads, the poster offered insights into “the finger-like appendage of the porpoise penis, the extended urethra of the giraffe, and many other genitological oddities.” Knowlton included a descriptive text along with the poster, providing more information on each member: “The elephant has a very muscular penis. Half of the curved organ forms the pendulous portion, yet only the very end penetrates the hard-to-reach vulva of the female during copulation.”

The 23-by-35-inch poster was sold as both an “educational resource” and a “novelty for the general public”—though the object’s true novelty was tied up with the context of the culture wars of the late 1980s and early ’90s, when Knowlton’s design became an unlikely icon for some kind of countercultural protest. Exactly what kind of protest it was is still very much up for debate.


The illustrations that make up “Penises of the Animal Kingdom” are simple line drawings with the barest of shading to indicate depth. They look like the kind of thing a professor in a hurry might sketch on a whiteboard to illuminate some basic principle. Knowlton has said he was after a plain and clear illustration style, in the vein of Gray’s Anatomy. (“I drew them myself,” he once explained in an interview. “Very academic, nothing fancy or suggestive, not a lot of hard detail.”) But actual anatomical illustrations—such as those Henry Vandyke Carter did for Henry Gray’s original 1858 anatomical textbook—usually depict blood vessels and arteries, musculature, and organs and their mechanics, none of which are visible in Knowlton’s poster.

Ideally, graphic design conveys not just subject matter but also tone. But the tone here is muddled, and “Penises of the Animal Kingdom” seems deliberately ambiguous in its intention. Not quite scientifically drawn, as an “educational resource” it really only hits one note: comparative size, disconnected from context. Nor is it broadly comical, as it might be if it were truly aiming to offer “many hours of fascination and enjoyment.” At most, it’s an image worth a few minutes of analysis, the level of contemplation you might give to an image in a doctor’s office or on a friend’s dorm-room wall.

The clue to Knowlton’s intentions is right in the name of the company he created to sell the poster: Scientific Novelty Co. (The poster was the only thing the company would ever sell.) It’s scientific, to be certain, but also a novelty, in much the same way “novelty store” is a euphemism for a sex shop. Purposefully vague, it responds to our gaze with a knowing wink.

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Knowlton had been a graduate student at Columbia University, working on a PhD in particle physics, when he first concocted the idea for the poster. A colleague’s comment about how snakes have two penises, he later recalled, got him “thinking about penis trivia,” which soon “moved into the further realm of comparing.” He was 24 years old when he began selling the poster in 1985; after he completed his master’s, his academic funding was cut off. He moved out to Indiana, he later told a reporter, to continue selling his poster and start a rock band. The poster business was a one-man operation, and by then, Knowlton estimated, he was selling about 5,000 copies a year.

In 1992, the poster’s notoriety earned it an Ig Nobel Prize—a set of parodic counterparts to the Nobel Prizes that are awarded each year by Marc Abrahams, editor of the science-humor magazine the Annals of Improbable Research. “The prizes are not intended to say that anything is bad or good,” Abrahams says. Instead, the sole criterion is: “Does it make people laugh and then think?” Few laureates have made work that has fit these criteria as well as Knowlton’s poster does.

Knowlton’s Ig Nobel was jointly awarded to the National Endowment for the Arts, which was acknowledged, according to the citation, for “encouraging Mr. Knowlton to extend his work in the form of a pop-up book.” (The NEA claims it has no record of Knowlton applying for or winning a grant of any kind, and the pop-up book never appeared.) Abrahams denies that including the NEA in the Ig Nobel was an intentionally political decision, but he allows that controversy around the NEA “was very much in the air at the time.” The early 1990s was a fraught time for the arts agency, which had been under assault from conservative politicians for years. Grants supporting artists such as Robert Mapplethorpe, Andres Serrano, and Karen Finley, whose work pushed the boundaries of middle-class respectability, had earned the decades-old agency a reputation for “moral corruption,” and senators Jesse Helms and Al D’Amato led the charge to defund the NEA and restore “respectability and decency” to American art. Mapplethorpe in particular, with his black-and-white, sexually explicit photographs of gay men, had brought penises, popped-up and otherwise, to the forefront of the national conversation. And despite Abrahams’s denials, it’s hard not to read the presentation of a fatuous award to the nation’s premier arts agency—for its ostensible funding of what are, essentially, interspecies dick pics—as just one more shot fired in the culture wars.

There was something about Knowlton’s poster that got a rise out of people. In the late 1980s, the gentlemen smut-peddlers at Playboy repeatedly refused to run his classified ad, citing concerns over its “content”; even for a magazine about sex, Knowlton’s penises were taboo. The magazine’s prudishness was short-lived, though: after Knowlton had submitted the ad and been turned down, Playboy instead ran the image as an editorial illustration in its January 1991 issue, clipping his name and refusing him payment, which led Knowlton to sue for copyright infringement. (The suit was settled out of court, and in the May 1991 issue, Playboy ran a correction from Knowlton, in which he claimed credit for the poster and instructed readers on how to get their own copy.)

Playboy wasn’t the only magazine that struggled over what to do with Knowlton’s classified ads. In 1987 the advertisement had caused a major upheaval at The Nation, when the liberal magazine’s new publisher, Arthur L. Carter, tried to ban the ad. The staff was horrified—in part by Carter’s heavy-handed managerial style, but also because they felt a kinship to the poster and its values. In a joint letter to Carter sent on October 30 of that year, the staff called the poster “harmless” and explained to their new boss that “we view it in the context of a tradition of poster art in the United States that goes back to the early years of this century and that flowered particularly during the 1960s. As far as we’re concerned, the ad and the poster have a countercultural flavor.”

In an all-hands meeting a week later, Carter meekly pushed back, arguing on behalf of “middle-class values.” The staff doubled down. The poster seemed hardly worth such trouble—yet it meant something. As then-staffer Micah Sifry later recalled, senior editor Andrew Kopkind responded to Carter in front of the rest of the staff: “This matters because, whatever else you might say about The Nation, and no matter how late it came to this realization, it still is a place that embraces the values of the ‘60s and of the counterculture. And at a time those values are under attack and are being repudiated right and left, part of our project is to celebrate those values, the idea of liberation, and so on.” Demagogues like Pat Buchanan had long been calling for a culture war between middle-class values and the counterculture, and Knowlton’s poster had emerged as an unlikely flashpoint for the publishing industry. It was time to stick up for it.

Such a high-minded response may have been a stretch at the time. Knowlton’s work lacks the artistic seriousness of Serrano’s Piss Christ or Mapplethorpe’s photographs; it lacks even the transgressive impulse of underground comics, such as the scatological works of Robert Crumb. Knowlton’s poster was sober and clinical, and one could hardly say that it was trying to stick it to the man.

Certainly pictures of penises, human or non-, were and still are fairly taboo. The penis lurks behind culture, symbolically ubiquitous yet all but invisible outside of hard-core pornography. In the 1993 book Running Scared: Masculinity and the Representation of the Male Body, author Peter Lehman suggests that depictions of penises cause anxiety for men in a number of ways. Given the large disjunction between the phallus—a symbolic object that appears throughout human culture, from tribal art to skyscrapers—and the biological penis, the latter always risks underwhelming by comparison. Further, Lehman notes, “Heterosexual men may fear that the representation of the penis gives women a basis for comparison and judgment, and, although men have long engaged in such behavior toward women, the thought of the tables being turned is nearly unbearable.”

As a result, representations of human penises tend to be strictly regulated. In pornography, they are comically large and perpetually erect, while medical depictions feature rigorously average, perfectly middle-of-the-road specimens, so as not to offend. Knowlton’s penises fall into this latter category. The description in the poster’s accompanying text is clinically detached (“The human organ possesses a well-defined glans, or tip. This mushroom-shaped end is one of the most evolved glands of the animal kingdom”), the drawing simple, unremarkable.

Knowlton’s poster is phallocentric, of course, but at the same time rejects anthropocentrism, which is its true provocation. The sexual mores it violates are less sacred than the myth that humans are any more interesting—or less bizarre—than any other animals out there.

Here was a comparison that was scenically accurate in its phallic cruelty, a poster that reminded men about their rightful place in the animal kingdom—not at the top, but at the very bottom.

The joke, to the extent that there is one, is in the ranking, wherein the human penis ends up last and smallest, behind even that of the dog. Of course, Knowlton could have found smaller penises to round out his list—a cat perhaps, or even a mouse. That he chose to end with a human member is a pointed gesture, suggesting inadequacy. Forget the judgment of a woman, here was a comparison that was scenically accurate in its phallic cruelty, a poster that reminded men about their rightful place in the animal kingdom—not at the top, but at the very bottom.

After the Playboy lawsuit and the Ig Nobel, Jim Knowlton got a fair amount of press, which he used to drum up interest in his modest poster. But by the second half of the 1990s—after tens of thousands of posters had sold—the project had run its course. The ads stopped appearing in the backs of magazines, and Knowlton faded from public view. (He now lives a quiet life in Indiana, and did not want to be quoted for this story.) His poster has faded a bit, too, though it still pops up on eBay and has a featured spot in Reykjavík’s Icelandic Phallological Museum, which claims on its website to be “probably the only museum in the world to contain a collection of phallic specimens belonging to all the various types of mammal found in a single country”—a museum devoted to the “ancient science” of phallology, “which, until recent years, has received very little attention in Iceland, except as a borderline field of study in other academic disciplines such as history, art, psychology, literature, and other artistic fields like music and ballet.” The poster’s inspiration also lives on in a phalanx of “Bizarre Animal Penises” clickbait lists online. But those lists don’t include the human penis, of course, since the “bizarreness” of other animals’ reproductive organs is always judged in reference to our own. The important thing about “Penises of the Animal Kingdom” is the inclusion of human anatomy as no more or less remarkable than that of the pig or hyena. The great generative organ of human civilization is just one more dumb prick.

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