Thanks to Smithsonian Magazine for this hilarity:
The more scientists learn about penises, the more they realize how varied sex organs are.
Just ask Emily Willingham, a biologist and journalist who’s been studying penises for over a decade.
Her book, Phallacy: Life Lessons from the Animal Penis, just came out. Phallacy plunges readers into the wild and wacky world of animal genitalia while exploring the social and cultural significance of penises as symbols of power and identity.
The Echidna’s 4-Headed Penis
The echidna, a spiny egg-laying mammal, which has evolved a four-headed penis. During copulation, echidna penises operate on a part-time schedule: half the penis temporarily shuts down while the other two heads are responsible for fertilization. But those extra two heads aren’t there just to show off. Next time the echidna mates, he’ll alternate which half he uses. By shutting down half of their penis at a time, male echidnas fit perfectly with the female’s two-branched reproductive tract.
Dolphins have particularly dexterous phalluses.
Dolphins are known for their intelligence, promiscuity and absurdly dexterous penises. They have a prehensile penis, meaning it can swivel, grab and grope, much like a human hand. A prehensile penis helps males navigate the complex, labyrinth-like reproductive tracts of female dolphins.
Dolphins don’t just use their penises for baby-making, either. Bottlenose dolphins frequently copulate for pleasure, and often with members of the same sex. Dolphin sex doesn’t last long, only about 10 seconds, but males can ejaculate multiple times an hour.
Penis of the Flatworm
Many animals use their penises for love, but flatworms also use their penis to fight.
Like many organisms with intriguing phalluses, flatworms that engage in penis fights are hermaphrodites—just one example that showcases how a sex binary system fails to account for the range, fluidity and diversity of many organisms. Some species of flatworm engage in this duel to see who can inseminate the other.
Their two-headed penises resemble tiny swords, and battles can last for up to an hour as they take turns attempting to stab the other. The winner pierces the flesh of the other flatworm to deposit their sperm, something scientists refer to as “traumatic insemination.”
Mating can be competitive, with a single flatworm fertilizing another. In other cases, like with the tiger flatworm, they can play both roles: each flatworm gives and receives sperm from its partner.
Blue Whale Penis (8-10 feet long!)
Blue whales have the largest penis in the animal kingdom—around 8-10 feet long!
Blue whales are the largest creature to ever roam the earth, and they certainly have the phallus to match.
Blue whale penises range between eight and ten feet, with a foot-long diameter.
Each of its testes along can weigh up to 150 pounds and can ejaculate gallons of sperm in a single go.
Whale penises are so famously oversized that in Moby Dick, Herman Melville suggests using the skin of a sperm whale’s phallus as a floor-length apron to stay tidy while skinning the rest of the whale. We’ll have to take Melville’s word on that one.
Yes, even Barnacles have Penises
Barnacles have penises nearly 8 times their body length.
Barnacles have the biggest penis-to-body size ratio, with genitalia nearly eight-times their total body length.
Barnacles are stuck in place for life, so they use their super-long penises to reach other nearby crustaceans, blindly depositing sperm inside their neighbors. Like flatworms, barnacles are hermaphrodites that can fertilize others, be fertilized or both.
If humans had the same penis-to-body-sized ratio as barnacles, our penises would be about 50 feet in length, says Willingham.
Bed Bug Penis
Bed bugs stab their partner during copulation.
Bed bugs are famous for their aggressive, stabbing sex. Sometimes, overzealous males kill females with their saber-like penis in the process.
Willingham explains that this violent process has caused bedbugs to evolve “something very vagina-like where they tend to get stabbed.” This special less-armored area of their abdomen might minimize harm as the male injects his sperm into the female’s circulatory system.
Sea Slug Penis
Meet Chromodoris reticulata, a type of sea slug, that has to reckon with a scary reality: sex means saying goodbye to their penis. At least, for the day.
Chromodoris reticulata are hermaphrodites and fertilize each other simultaneously during sex. Each has a 3-centimeter-long schlong, but they only extend a centimeter of their penis when copulating.
After sex, they shed their single-use penis into the ocean’s abyss. But this loss doesn’t mean their sex life is over: they have at least two more disposable penis segments hidden away. As soon as 24 hours later, the slug will be back in action.
Leopard Slug’s Giant Electric Blue Penis
Leopard slugs sport giant electric blue penises.
Sometimes, penises pose logistical challenges. That is certainly the case for the leopard slug, which is so well-endowed that it has to go to extreme measures to reproduce.
Once copulation is complete, one partner slurps down the slimy sex rope as a post-coitus snack.
Mating leopard slugs dangle from branches by a shared rope of their own slime with their penises hanging below. As hermaphrodites, these slugs inseminate each other during sex so, once the action starts, two penises are on display. And their penises are easily spotted: They’re electric blue and roughly the size of the slugs themselves.