Evolution of the Dog

This is a story about you and me and your dog.

There was a time not long ago...before dogs. They didn't exist. Now there are big ones, small ones, snugglers, guardians, and hunters. Every kind of dog you could possibly want.

How did that happen?

It's not just dogs. Where did all the different kinds of living creatures come from?

The answer is a transforming power that sounds like something straight out of a fairy tale or myth, but it's no such thing.

Let's go back across 30,000 years to a time before dogs, when our ancestors lived in the endless winter of the last ice age. Our ancestors were wanderers living in small bands. They slept beneath the stars. The sky was their storybook, calendar, and instruction manual for living. It told them when the bitter colds would come when the wild grains would ripen when the herds of caribou and bison would be on the move. Their idea of home was Earth itself.

But they lived in fear of other hungry creatures... the mountain lions and the bears that competed with them for the same prey and the wolves that threatened to carry off and devour the most vulnerable among them.

Think if you are with a campfire at night and a group of wolves are surrounding you. Actually, the wolves are too frightened to attack you because you may have a fire or something to defend. If you throw a bone at them, All the wolves want to get at the bone, but most of them are too frightened to come close enough.

Their fear is due to high levels of stress hormones in their blood. It's a matter of survival. Because coming too close to humans can be fatal. But a few wolves due to natural variations have lower levels of those hormones. This makes them less afraid of humans.

If one of wolf comes closer and get that bone, that wolf has discovered what a branch of his ancestors figured out some 15,000 years ago an excellent survival strategy; the domestication of humans.

Let the humans do the hunting, don't threaten them, and they'll let you scavenge their garbage. You'll eat more regularly, you'll leave more offspring, and those offspring will inherit your disposition. This selection for tameness would be reinforced with each generation until that line of wild wolves evolves into dogs. You might call this "survival of the friendliest."

Then as now, this was a good deal for the humans, too. The scavenging dogs weren't just a sanitation squad. They worked security. As this interspecies partnership continued over time, the dogs' appearance changed also. Cuteness became a selective advantage. The more adorable you were, the better chance you had to live and pass on your genes to another generation. What began as an alliance of convenience became a friendship that deepened over time.

To see what happens next, let's leave our distant ancestors of some 20,000 years ago to visit the more recent past during an intermission in the Ice Age. This break in the climate starts a revolution. Instead of wandering, people are settling down. There's something new in the world... villages. People still hunt and gather, but now they also produce food and clothing…. agriculture.

The wolves have traded their freedom in exchange for a steady meal. They've given up their right to choose a mate. Now the humans choose for them. They consistently kill off the dogs that can't be trained and the ones that bite the feeding hand. And they breed the dogs that please them.

They nurture those dogs that do their bidding... hunting, herding, guarding, hauling, and keeping them company. From every litter, the humans select the puppies they like best. Over the generations, the dogs evolve. 

This kind of evolution is called "artificial selection" or "breeding”. Turning wolves into dogs was the first time we humans took evolution into our own hands. And we've been doing it ever since to shape all the plants and animals that we depend on.

In a blink of cosmic time, just 15,000 or 20,000 years, we turned grey wolves into all the kinds of dogs we love today. Think of it. Every breed of dog you've ever seen was sculpted by human hands. Golden Retriever, Rottweiler, Cane Corso, Doberman, Labrador, and German Shepherd like many of our best friends. The most popular breeds were created in only the last few centuries. The awesome power of evolution transformed the ravenous wolf into the faithful shepherd who protects the herd and drives the wolf away.

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