When you look at a tiny Pomeranian or other little dog, it is hard to imagine that its ancestors were once wolves. Sure, some of the bigger dogs out there it is easy to believe, but even Great Danes and Pit Bulls are dramatically different than ancient (or even modern) wolves.

Long ago, wolves were an apex predator that humans knew to stay well away from. Like humans, they were pack hunters, so if our ancestors saw one of them, they knew that there were more hiding about.

This begs the question, at what point did these terrifying animals become our best friends?

Not surprisingly, it did not happen all at once. Estimates say that wolves were first domesticated around 40,000 years ago. Initially, however, it wasn’t so much domestication as it was two species engaging in mutually beneficial behavior. The humans got protection from the wolves, and the wolves got access to our food and resources.

Over time, however, the wolves evolved into dogs, and according to a study published in the journal Science, that seems to have been around 10,000 years ago that the changes were enough to classify it as a new species.

The team studied 643 canid skulls that have been found, dating back as far as 50,000 years. Using 3D scans of the skulls, they could tell when the domestication traits really became prominent. Domestication causes animals to have smaller teeth, shorter snouts, a more rounded skull, and other changes, which is what the scientists were looking for.

Even at that point 10,000 years ago, however, the dogs would have looked much more like wolves than what we see today.

As humans learned the science of selective breeding, which would have been sometime after this point, they could control for specific traits that they were looking for, which would have accelerated this evolutionary process. That is how so many different breeds of dogs that look so dramatically different from each other were able to form over the generations.

Domesticating wolves has really worked out for the benefit of both species, most would agree.

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