h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

How do hamsters have sex? I presume that they do it the same as any other four legged animal, but I have never noticed a penis on a male hamster so I'm not sure.

I take it that you've never had a male hamster and the worry that its got bum tumours when it goes into heat? Apparently vets get that all the time, luckily my friend persuaded me not to make a fool out of myself. They were infact its balls. Fortunatly I have never seen a hamster having sex so I would not know how he did it, but your right about them not seeming to have a penis, maybe a vet will answer?

A large number of animals have no external penis except when in use..thus if you've never seen a hamster having sex then you won't have seen its penis.

In fact having an external penis is an evolutionary disadvantage - I can only presume that humans evolved in an area devoid of thorn bushes.

And then invented a metal zip. Hmmmm

I think most (male) mammals even small ones like hamsters and hedgehogs have what's called an ossified penis. A bony sheath stored inside the body helps to form the erection. Human males are the exception, since we use increased blood flow to "raise the flag".

Probably a byproduct of evolution and learning to walk upright, such a mechanism would play havoc with internal organs. I mean, it's pretty uncomfortable walking around with an unwanted (external) stiffy, but can you imagine one constantly nudging you in the steak & kidney pie you had for lunch?