Birds do it, bees do it—and sometimes it gets kinky.
Randy male hippos pull out all the stops to compete for the few eligible females in the pod: Bulls spin their tails as they urinate and defecate, spraying the vicinity with waste.
Long-distance relationships are hard. And when you're a barnacle permanently affixed to the bottom of a ship or rock, almost every relationship is a long-distance relationship. The good news: Hermaphroditic barnacles can still have sexual relations with their faraway—or not so faraway—loves with an inflatable penis that stretches up to eight times their body length, making it the longest in the animal kingdom relative to body size.
Another reason to hate bedbugs: They have no patience for romance! Instead of using a little foreplay in bed (or on a couch or movie theater seat or an entire Brooklyn apartment building), a male bedbug simply stabs the female in the stomach and releases his sperm into her circulatory system. Females can survive the act, thanks to a spermalege (a specialized region of the abdomen) that heals the wound. Male bedbugs that are accidentally impaled sometimes die.
4. Praying Mantises
Love can make you lose your head. Sex with a female praying mantis often will—especially in a lab and definitely if she's hungry. After some courtship dancing, a female will sweep a male off his feet and onto her back for fertilization. Once he finds his rhythm, she sometimes bites his head off. Some scientists believe it makes the male thrust harder. Others say it makes mating last longer, increasing reproductive sex. But we definitely know that it isn't good for him.
Talk about a stage five clinger. Male anglerfish lose their digestive systems when they reach adulthood, so after hatching, they immediately bite and attach to females like a parasite. Their bodies waste away, but that doesn't mean romance dies. The lump left on a female's body contains a male appendage to fertilize the female's eggs 'til (her) death do they part.
En guarde! Hermaphroditic flatworms can play the male or female role when mating, but they prefer the former. Instead of taking turns or playing rock-scissors-paper, flatworms whip out their sharp, dagger-like penises for a violent fencing match. The loser gets pregnant—the first stabbed flatworm absorbs the other's sperm.
When ducks screw, they literally screw. Males and females have corkscrew-shaped genitalia that fit together like lock and the completely wrong key—the genitalia spiral in different directions. The Argentine lake duck's junk is as long as its body, measuring in at about 17 inches long. The mating scene for these birds is notoriously competitive—pair-bonding is rare, and females play very hard to get. So well-endowed drakes use their penises as lassos to grab females and as brushes to clean other drakes' sperm out of oviducts.
Females porcupines are only open to mating a few hours a year. To figure out if a female's in the mood, a male stands on his hind legs and urinates all over her. If she shakes off the urine in disgust, he's not getting any action. But if she exposes her underbelly, it is so on. And on and on. Porcupines mate many times until they're both exhausted.
9. Banana Slugs
Size matters to the bright yellow banana slug. Not only do these hermaphrodites have penises the same length as their bodies—six to eight inches—they could lose their family jewels altogether if they’re not careful. For reasons that are still slightly murky, banana slugs have been known to bite the penis off of the slug they just mated with ... and probably stop returning its texts.
10. Honey Bees
There are worker bees and then there are the drones, males specially selected to service the queen bee. To make their fertilization efforts count, their genitals have evolved to snap off inside the queen to provide sperm for years to come. The drones die soon after, never to see the future generation.
11. Soapberry Bugs
Louis J Bradley, Wikimedia Commons
Of course, an animal doesn't always sacrifice its naughty bits for an evolutionary advantage. The soapberry bug gets clingy instead. During mating, males and females are physically stuck together—rear end to rear end—for up to 11 days. Some of these bugs won't separate until it's time for the female to lay eggs. And once she's done? More mating.
12. Garter Snakes
Post-hibernation, female red-sided garter snakes secrete a pheromone that brings all the boyssss to the yard. Hundreds of male snakes convene to form a large mating ball. Fortunately, their two hemipenes—penises on either side of the body—make penetration easier during the slithering orgy.
Like many a Tinder flirtation, male and female jellyfish never meet. But that doesn't keep them from making babies. Males release sperm through their mouths and leave it in the water. Females either keep their eggs in pouches near their mouths and swim through the sperm, or keep eggs in their mouths while sperm swims into their stomachs. When the eggs hatch, the swarm of larvae, known as planula, of many species attach themselves to a hard surface and buds on its own.
14. Garden Snails
Garden snails could teach Sting a thing or two about tantric sex. The hermaphroditic gastropods stroke, bite, and fondle each other for up to six hours before the hydraulic pressure builds and they shoot love darts at their mates. And no, that's not a euphemism. The mucus-covered darts are full of calcium and shot pre-sex to increase the amount of sperm that ends up in the female. Too bad snails can't see what they're doing—their genitals and dart sacs are right behind their eye-stalks. Like Cupid's arrows, love darts often miss their target.
Some men will give you their hearts, but the argonaut, or paper nautilus, actually gives away its penis. Sperm is stored in a special tentacle called the hectocotylus. When a male argonaut finds a mate, it simply releases the tentacle and sends it swimming over to the lovely lady. It all works out, because male argonauts only mate once in a lifetime and don't need their genitals for later. Save yourself for someone special, guys!