The idea of the dog as a tame wolf has a huge romantic attraction for us. We imagine the great grey wolf of the northern regions of the Earth, a powerful wild animal weighing 160–220 pounds, who spends his days hunting deer, moose or elk. We dream of our own ancestors finding (or stealing) a wolf puppy and raising him with lots of TLC. We imagine this pup growing up to be man’s friend and companion, and bearing tame pups for us. After thousands of generations of this, we supposedly produced the dog as we now know him. We see a direct line of descent going from our own dog straight to the mighty grey wolf we see on the Discovery Channel. Wow, a wolf in our living room, what a powerful feeling!
We now know that this isn't how it happened. Our ancestors didn't tame the dog at all. The dog most likely tamed himself. Besides, the dog’s ancestor isn't the mighty grey wolf of the Discovery Channel. That wolf didn't exist when the dog began to split off into a new species — the grey wolf as he is today had yet to evolve, just as the domestic dog did. What you need to imagine is a much smaller animal, who had already split off from the wolf family line some 200,000–500,000 years ago. This ancestor wasn't a specialised hunter like the wolf is, but rather what biologists call a ‘generalist’ — an animal that is not limited to one special food source or environment, but that can adapt to various situations. This smaller ancestor probably looked somewhat like the dingo and other primitive dogs who still live in the wild today. It may not have been a pack animal. In fact, pack living is rare among canids. So, like most of the generalist canids we see today, the dog’s ancestor probably lived in pairs and temporary family groups, able to deal both with being together and with being alone.
So now you are picturing a smaller, more dog-like kind of animal. What did this pre-dog animal do that led, in the end, to the present day dog? And did we have anything to do with it? The answer to both questions lies in our own development as a species. Like most species, we struggled along for millions of years, our numbers limited by the availability of food. Then, about 130,000 years ago, we invented the bow and arrow. This was a great leap, but — contrary to the myth — it didn't mean that the dog’s ancestor immediately joined us to help with the hunt. The dog was still just a wild animal, and like all wild canids — right up to the present, and even if they are raised in a human home — he remained totally useless to us during the hunt.
So our bow and arrow didn't mean that some wolf was suddenly able to work as a tracking and hunting dog, as the myth tells us. It did mean that our ancestors suddenly had a much easier time getting enough to eat. They started to leave small dumps behind at their encampments, dumps where there were edible leftovers for others to find. A new food source opened up for other species in the area. And when a new food source opens up in a particular environment, some animal always moves in to exploit it. In this case, a few of the sometimes hunting, sometimes scavenging, small ancestors of the present day dog were the ones who made the move. These were individuals who were attracted to a much easier (and safer) way to make a living. All they needed to do was trail along behind groups of humans and eat at the dumps we left behind. Perhaps they still ran into roaming, human-fearing relatives occasionally when their paths happened to cross, and perhaps they sometimes still mated with these animals — but most of the pups would come of mating at dumps, between loner animals who were now getting a living by scavenging our waste. This was the beginning of the reproductive separation, and thus of the formation of a separate species.
So, probably about 130,000 years ago, we have a number of these dog-like ancestors who split off and entered a new ecological niche. Partially reproductively isolated in this new niche, they began to develop specifically doggy characteristics. In order to meet at the dump and thus be able to mate, these animals had to have special qualities. They had to be prepared to eat ready-made food instead of hunting (the food you give your dog is, up to this day, still made of our waste, even the most fancy and expensive brands). If they lived in groups, they had to be willing to give this up in favour of wandering around alone or in pairs (even at the dump, there wouldn't have been enough food for a large group). They had to be able to share space (the dump) with strangers of their own species who had also discovered this new source of food. And — most important of all — they had to have a less-than-average fear of humans. These animals were in the process of making a choice. They were farther from their cousin the wolf than ever, but they weren't domestic dogs yet, either.
The choice that some of them made led them down the road to becoming, at this juncture, a sort of pre-domestic dog. This animal’s anatomy was still adjusted to a life of travelling as they trailed along behind groups of nomadic humans. This is probably why archaeologists don’t find typically doggy remains from this period. The dog’s body hadn't changed yet, even though his behaviour and his brain were already changing. But before this animal could become a real domestic dog, our own species had to make its next step.
This next step came about 12,000 years ago, when we developed agriculture. Humans stopped roaming as hunters and gatherers, and started living in permanent settlements. Now the pre-dog could also settle down and live permanently at the dump. Now he wouldn't run into relatives who were still hunting and still shy of humans, not even by accident. There would be no more mating with hunters, not even occasionally. His body could now adapt to a non-travelling life, besides the changes that had already taken place in his brain and behaviour. Within a very short time, the dog as we know it today was a fact. This is the period when truly doggy skeletal remains showed up. The other branches of the family continued on their hunter’s way, and became the wild dogs you now see on the Discovery Channel. The present-day grey wolf has nothing to do with it.
Fact - The dog and the wolf are related to each other in the same way you are related to your sixth cousin, and in the same way we are all related to some other types of primates (monkeys and apes). We share an ancestor, that’s all. But the dog most definitely didn't descend from the grey wolf, any more than you descended from your cousin.
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