Weird Sex in the Animal Kingdom

by Allie Wilkinson on February 14, 2009

Banana slugs

The male banana slug’s penis is the same size as his body, so he needs to find a female the same size as himself.  Otherwise, his penis is too big for her and she chews it off.


Female porcupines are only interested in sex for 8-12 hours out of the
ENTIRE YEAR!  Males have to woo their woman by peeing all over her from 6 ft away.  If she’s into it, then she makes him mate over and over again, until he is exhausted.  If he’s done before she’s had enough, she leaves him for another male.


Everyone has sex with everyone else, for any reason at all.  ”Hey, you brought home fruit?  Let’s do it!”


Ah, the art of penis fencing.  Since flatworms are hermaphrodites, they duel to see who will be the male and who will be the female.  Whoever gets stabbed first by the penis gets to be the woman.


The males are definitely jerky in this species.  You see, the female carries her eggs around in her mouth.  The male has spots on his anal fin that look like eggs.  So the female, thinking she dropped some, moves in to pick up her “lost eggs” and in the process gets a faceful of sperm, compliments of the male.


Only around a dozen male drones get to mate with the queen bee out of a thousand or so, but their genitals explode and their broken-off penis acts as a cork to keep their sperm inside the queen.


And here, you thought your boyfriend was a parasite!  Once the male anglerfish reaches maturity, his digestive system shuts down.  Since he can’t eat or digest food on his own, he finds a female, bites her and releases an enzyme that bonds them together permanently.  Voila!  No work required by the male, except for releasing sperm every now and then.

Brown antechinus

This little marsupial is so sex-crazed, that he will hump until he keels over and dies of exhaustion.  He will spend up to 12 hours mating with one female.  YIKES!  Insatiable to the core, he goes from female to female, mating until his immune system becomes suppressed, he develops severe ulcers and gets infected by parasites and dies at the end of the mating season.


Talk about dominant women!  The female hyenas are more aggressive than their male counterparts, and are even equipped with a pseudopenis (basically a realllly large clitoris).  The males then have to artfully insert their penis into the pseudopenis in order to mate.

Percula clownfish

In a family group, the largest member is the female and the second-largest is the male.  When the female dies, the male then switches sex and becomes the female of the family.


Snails are also hermaphrodites.  Strange fact: their penis is located on their neck!  As put it, even though they have both parts, they still need a mate because snails, like Jesus, frown on self-love.  Instead they stab each other with calcium “love darts” to convince their partner to trade sperm packets.


Panda porn.  Got to see some of that at the 2007 SCB conference, while sitting with my dad. AWKWARD.  It’s no secret that zookeepers have had issues breeding pandas in the past.  Now pandas of a certain age are shown “panda porn” to get them in the mood.


The male hippo will put himself on display, defecate on himself and use his tail like a propeller to spread it around, in the hopes of attracting  a mate.

Red-sided garter snakes

The female ends up in a giant snake orgy called a mating ball, which can consist of up to 100 males all trying to mate with the one female.  It’s a big tourist attraction up in Manitoba, Canada.

Argentine lake duck

This duck has a 17 inch long, corkscrew-shaped penis, with a brush on its end.  It uses the brush to remove any sperm left by a previous male.  And if its female tries to escape, he uses his penis as a lasso to bring her back.

Whiptail lizards

These guys aren’t guys at all.  None of them are.  They are ALL females.  How do they reproduce, you ask?  They engage in a little girl-on-girl humping to encourage the female to reproduce on her own and produce an exact clone of herself.


The phrase “traumatic insemination” says it all.  Male bedbugs have such sharp penises, that they basically just stab through the female’s body to deposit their sperm.

Sea hares

Yet another hermaphrodite, sea hares will form a line or circle, one upon the next, to mate.


Also known as the paper nautilus, this is a species of octopus.  The male  produces a ball of spermatozoa in a special tentacle called a hectocotylus.  When he sees a female he likes, the male then detaches his penis to swim by itself to the female!

Hectocotylus (Image Credit: Julian Finn, Macalogist)

This detachable swimming penis was actually first noted by an Italian naturalist back in the 1800s, who mistook it for a parasitic worm!

Its a matter of size

Here’s some info you wouldn’t expect.  Barnacles have the longest penis to body ratio in the entire animal kingdom.  The penis can be up to 50 times the size of its owner!  Yet gorillas, which can weigh up to 450 lbs or so, have penises less than 2 inches long!  Stranger yet: the world’s longest sperm actually belongs to fruit fly of the Drosophila bifurca species.  Once uncoiled, a single sperm measures 2 inches long, which is 1,000 times the size of human sperm!

{ 11 comments… read them below or add one }

Christie February 15, 2009 at 11:41 am

Hee hee “penis fencing”


Allie Wilkinson February 15, 2009 at 8:59 pm

bonobos engage in penis fencing too, but its more of an homosexual maneuver than a “who’s going to be the woman?” one.


annabones February 15, 2009 at 9:30 pm

Newfound appreciation for the human male penis.. (in case I ever stopped appreciating it anyway)


Jenni February 16, 2009 at 12:05 am

As requested, this is a bit of additional information on the red-sided garter snake: Males awake from brumation (reptile version of hibernation) slightly before the females. This gives them enough time to travel around, eventually congregating at the outside of the resting place of a female. When the female comes out, all of the males jump on her. Now, snake reproduce by inserting their hemipenis into the cloacal vent on the other snake. The males don’t know who is who at this point, so they insert their hemipenis into ANY cloaca they can find, immediately blowing their load, and then repeat the entire process until everyone is too exhausted to continue.

It’s the snake equivalent of the woman waking up in the morning, and on the way to the bathroom, getting jumped by a massive mostly-gay gang bang.

Yay herpetology! :D


whysharksmatter February 19, 2009 at 9:50 pm

You didn’t mention the awesome diversity of reproduction found in sharks! Male sharks have not one, but TWO claspers, which clasp onto the female to make sure she doesn’t leave before the male is done! Some sharks lay eggs, some have live birth. Some can even clone themselves via parthenogenesis!


RecycleBill February 21, 2009 at 5:12 pm

And to think, I thought chicken sex was wild.

For those who might not know, chickens have no external sex organs– the rooster violently mounts the hen and sprays her in hopes that she might push what looks like a pink ball out of her rump. If his spray hits the pink ball she becomes fertile but 99% (guesstament) of the time she doesn’t let that happen. It usually takes him 3-5 seconds but he mounts a hen every few minutes all day long in the hope that he might hit the target and amazingly he does.


Ed Yong March 1, 2009 at 7:28 pm

See also the spiky terror-penis of the seed beetle. With pictures.

Allie asked me to post this link so don’t blame me if it forces you want to run screaming for the hills or scrub your eyes. ;-)


Chainsaw August 22, 2009 at 10:38 pm

It opens up whole new worlds of potential kink.

I don’t think traumatic insemination or exploding penises are going to catch on, but there are some ideas there…


John Logsdon January 20, 2010 at 8:13 pm

no better subject than this!


=_= December 21, 2013 at 5:35 am

Okay so I watch the videos about bee sex and snail sex….
I’m just sitting there going WTF? And then when I finished reading I though
“WTF? I searched up animal reproduction! Not sadistic snails and exploding sperm balls


Allie Wilkinson March 1, 2009 at 7:37 pm

I don’t know, traumatic insemination of bedbugs already scarred me for life. I was traumatized just reading about it. Doubt anything else can scare me worse than that!


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