whoah.

And no penis discussion is complete without mention of the cat penis, which sports spines that act like a bunch of barbs in the female cat's nether regions, triggering her ovulation.

::shudder::

It makes you realize that - as far as penises go - humans have a pretty sweet deal. If you're into that sort of thing.

cannot unsee.

Cracked talked about this in an article a bit ago. apparently sometimes there's a, like, prolapse situation, and things need to get manual.

There are worm species that have penises but no corresponding orifices so they just STAB EACH OTHER with their penises

I'm at work, but Isabella Rossellini has a series that someone should definitely link to here.

This is the article I was born to comment on.

Did you know that snakes have a forked penis? Each fork is wired to a single testicle, and they can ejaculate separately. This has been tested by putting tape over one side of the penis, then the other, and allowing the snake to mate. Female snakes can store sperm in a suspended state for YEARS before allowing it to fertilize their eggs.

It is called a hemipenis, and there are pictures and more information at this link: http://snakesarelong.blogspot.com/2014/03/why-do-... (Note the clever ars longa vida brevis pun in the blog title, this person is amazing.)

What about alligators? Turtles have that huge penis because they need to navigate shells, but fertilizing an alligator also requires... distance.

Solution: two foot ghost white bungee penis. Of course I have a link http://phenomena.nationalgeographic.com/2013/02/1...

Finally! A place I can talk about my most memorable zoo visit!
I went with a neighbor's kids to the zoo. They have an outdoor cheetah, and an outdoor giant tortoise exhibit. While the children were running back and forth trying to get the cheetah to race, I kept hearing these oddly spaced out ....grunting?noises. Very widely spaced out. Then I turned around to see the tortoises mating. Very slowly. In time with the noises.

But turtles: I talked earlier about the alligator collagen penis, right? The permanently erect thing that is contained inside their torso? That's what this turtle has in the first bit. Then at the .22 mark, where there is more unexpected penis? That is the lymph-filled penis, a system that works a lot like how the mammal penis works (except with lymph instead of blood), but evolved separately. (Our distant ancestors were hydraulic, and apparently we both default back to hydraulics when we have to design something that engorges. This is where turtles and humans share a nice recognizable trait with our closest non-chordate relatives, sea urchins and starfish, which is great because otherwise you have to look at a lot of embryos. Penises are basically starfish feet.)

The turtle has a tube to channel sperm in the collagen bit, and a groove in the lymph bit, and then viola, the eggs in the rollerblade are fertilized. Success!

The collagen penis is so tough, long, and motile enough that male turtles commonly use it to dislodge themselves if they are stuck between rocks. You know the upside-down turtle being all helpless? Male mud turtles commonly use their penises to turn themselves right-side up.
http://blogs.scientificamerican.com/tetrapod-zool...

You know, I know we're supposed to be appalled by this, but...the turtle was enjoying himself andthe rollerblade's inanimate, so no harm done. Nature is weird and beautiful and mostly weird.

Also, the expressions on his face! And the way he sprawls over in the ecstasy of consummation at the end!

I regret watching this in a public library.

Am I the only one very concerned about the child witnessing this??

Sixty-odd comments and not a single person's mentioned echidnas?! Their penises have four heads, but only two heads are active during sex (the side alternates). And echidna females have a dual-branched cloaca and lay eggs. Monotremes are weeeeeeeird. https://pygmylorisreid.wordpress.com/2012/07/06/1...

After the initial horror of the revelation, I find myself extremely curious about how a turtle knows when it's found that special rollerblade.

Chelonian anatomy aside, I think we can all agree: that is one incredibly sexy-looking roller skate.

Remember that one chapter in Moby-Dick, where Ishmael describes a particular feature of whale anatomy, only he doesn't ever exactly say what it is, just that it is remarkably large and impressive and hefty and worship-inspiring? And he tells how the whalers will skin it, then climb inside the skin and wear it around the ship? What a great book.