8 Bizarre Things Science Has Taught Us About Sex

5. Men Lost Their Penis Bone And We're Not Sure Why

Back in our evolutionary past, the "!*$%" was a lot more, er, literal.

Like so much of the animal kingdom, the human penis used to have an actual bone in it to keep it erect. In more horrifying news, it's thought that it also had spines.

The penis bone, or baclum, usually sits in the body and is pushed out when it's time to get it on. This would ensure that the gentleman in question could maintain the erection for as long as necessary, and wouldn't have to mess around getting "warmed up" if just a quickie was on the cards.

Nowadays, however, men have to rely on blood pressure alone. It's not entirely certain why this particular trait won out on the evolutionary stage, but some reckon it has to do with picking a strong mate.

If a bloke can maintain an impressive lob on through the power of blood alone, it might indicate to a potential lady-friend that he is super fit and healthy, whereas you never can tell if they're relying on a bit of scaffolding.

The spines probably died out because, you know, would you want to put something spiky anywhere near your hoo ha?