Pandas in Love

We all love animal babies, but we bet you probably have no idea what some animals have to go through just to perpetuate the species.

From reptiles who never have sex to lions who get frisky 100 times in a day, here are some curious ways that fellow creatures procreate.

Too Much of a Good Thing

Humans tend to think that we’re the only species that has sex for fun, but some animals do it with way more enthusiasm than seems necessary just to get pregnant.

Take female lions, who are in heat for four days — and mate every 15 minutes all day and night during that time period. That adds up to about 100 times per day, and 1,500 times for each litter that they produce. Meanwhile, for every infant that female chimps give birth to, they mate an average of 138 times, with 13 different males.

Ever wonder where that popular phrase, “the birds and the bees,” came from? Well, consider the way some birds go at it: Kestrels and oystercatchers do it 700 times per clutch of eggs. For more restrained birds, like tree swallows, 50 to 70 times will do.

Instead of doing it repeatedly, some animals really make it last. The male Panamanian golden frog gets on the female’s back and clasps her in a posture called amplexus, hanging on until she lays her eggs — for a couple of months! Since it’s hard to catch live insect prey in that position, the males come close to starving.

Then there’s the antechinus, an Australian marsupial that looks like a mouse. All the females come into heat at the same time, so the males go into a frenzy, fighting to do it with every girl in sight. They spend up to 12 hours at a time mating, and at the end of the two-week breeding season, the males are so exhausted that they all drop dead. And they don’t all get to leave behind offspring, either: Only the strongest males actually fertilize a female’s eggs.

Animal Abstinence

Not all animals have such an active sex life — for some critters, it’s a truly rare activity.

Female pandas, for example, are only in the mood once a year, for a small window of just 36 hours. Since they’re solitary animals, it’s not that easy for a male to run into a female at exactly the right time to make a baby panda, giving new meaning to the term “get lucky.”

There are even creatures who get pregnant without doing it at all. Parthenogenesis (virgin birth) occurs among plenty of simpler insects and reptiles, such as some species of whiptail lizards. Others will do it as a last resort when they can’t find a mate — like a Komodo dragon who surprised keepers at a British zoo in 2010 by producing a clutch of fertile eggs on her own.

Love Hurts

Already think bedbugs are gross? A male fertilizes a female bedbug by piercing her abdomen with his needle-sharp penis, and ejecting sperm directly into her body cavity. And some species of snails produce sharp “love darts,” which they “fire” at mates during copulation. Since the darts are covered with mucus, it allows the females to store more of their partner’s sperm.

Sometimes, if you truly love someone, you have to let that person go — but the water strider says to heck with that! The males have evolved a way to make sure that females can’t escape during lovemaking: Their antennae have prongs, bristles and hooks designed to hold females down by their eyes.

It’s not just creepy crawlies that indulge in animal S&M, either. A male cat has barbs on the end of his penis. When he withdraws, it scrapes a female’s insides, making her scream and lash out at him. The act is actually required to kick start ovulation, so no pain, no gain.

Kinky Creatures

Causing pain isn’t the only weird way that animals do it.

Spiders go so far as to produce their own ropes. The male crab spider, for example, ties the female down with his silk before mating. To be fair, it’s something of a safety measure, since female spiders have a reputation for eating their mates.

Group sex is also common among many species. At the end of hibernation, male red-sided garter snakes wake up first, and as soon as they see a female emerge, they all surround her, forming a rolling mass called a “mating ball.” Something similar happens with green anacondas — and they can stay massed together for up to a month.

Just Plain Weird

Some animal sex is so bizarre that there are no categories for it. Case in point: Female and male anglerfish become permanently attached to each other. When a male encounters a female — who’s ten times bigger than he is — he latches on with his sharp teeth and starts to physically fuse with her body. He ends up sharing her bloodstream, as well as losing his eyes and non-crucial internal organs. Once he’s reduced to a pair of testes, the female can get pregnant whenever she wants, making him quite the kept man.

Linda Lombardi is a former zookeeper, college professor and the author of Animals Behaving Badly, a book that grew from her blog of the same name.