Why does a dog lift his leg to pee?

I always thought it was a guy thing, but that's wrong. Female dogs sometimes do it, too.

So is it because he doesn't want to pee on his feet? Unlikely. Have you ever seen a dog pee on its feet?

Dogs lift their legs and let fly because they're trying to leave traces of their urine as high as possible. And why do they do this? Because the higher the mark, the bigger the dog. Size counts with dogs. A Rottweiler leaves a much higher calling card than a dachshund. People may not know the difference, but dogs do. And if you're a dog, you want to know if your new neighbor is a Chihuahua or a Great Dane. It matters. Just ask Bao.

What intrigues me is that it works the same for females as it does for males. The bitch who lifts her leg is telling the rest of the girls, Look out! I am one mean mother. Mind you, I'm not quite sure what she's telling the guys. Unless she's a Rottweiler, of course. In that case she may be saying, Dachshunds need not apply.

So next time you're walking your best friend and it's cold and you're late and you're tempted to tug at the leash, forbear. Your dog isn't just relieving himself, or herself. He (or she) may be composing the doggy equivalent of a letter to the editor.

Here's an interesting theory. Human beings didn't domesticate dogs. It was the other way around. Dogs domesticated human beings, and were also responsible for the development of human, spoken language.

All of this took place 100,000 years ago. One of the differences between our primitive, human forefathers and the Neanderthals was that our ancestors made friends with dogs whereas the Neanderthals did not. Dogs' superior sense of smell and ability to follow a scent was a big advantage, so our ancestors' cooperative partnership with dogs enabled them to become more efficient hunters than the Neanderthals.

But here's the kicker. Now that we had dogs to do the tracking for us, we no longer needed the snout-like facial structures that enabled us to pick up the scent of game. We could evolve more flexible facial features, which in turn gave us the physical capacity to shape more complex sounds -- which eventually became speech.

Meanwhile back in the caves, the dog-hating Neanderthals still needed their scenting ability and their relatively inflexible facial structures. So they were unable to create the complex sounds that led to the creation of human language. Not being able to speak was a big disadvantage, and the Neanderthals eventually died out. That's the theory, anyhow.