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.