Considering that dogs can breed with wolves and produce fertile offspring, they are defined as the same species. Obviously, however, there are huge differences between dogs and wolves. I am currently reading Coppinger and Coppinger’s book, Dogs: A new understanding of canine origin, behavior, and evolution (which I highly recommend), and some of the differences that they point out are:
- Dogs are more successful than wolves, and in fact any other canid. There are a lot of dogs in the world, and not so many of any wild species.
- Dogs come in a lot of shapes and sizes. Wolves come in one.
- Wolves are not very adaptable – environmental changes have considerably disrupted their populations. Dogs adapt well.
- Wolves are not highly specialised and are, indeed, a generalised predator. For any skill or sense, you can find a dog that can do it better than a wolf. (e.g. Greyhound run faster than wolves, Bloodhounds smell better, etc)
- Wolves and dogs do not behave the same.
- Wolves avoid people. Dogs live around or with humans, and indeed seek them for food.
- Wolves kill their own food, while dogs rarely hunt (and indeed are quite bad at it, if you consider The Trio of Dogs study I wrote about).
- Wolves are had to train and tame, while dogs, obviously, are biddable and tame.
- Dogs and wolves have different cognitive abilities. Wolves are better at problem solving, learning by imitation, and observation, while dogs learn from repetition. Wolves do cleverer things, but dogs are more able to be conditioned to do clever things.
Clearly, there has been a big change here. Dogs are the same species as wolves (Canis lupus), but are a recognised subspecies. There has been a lot of talk about how dogs eventuated, especially considering these very pronounced differences between wolves and their subspecies.
There seems to be two arguements to how this development took place.
One suggests that humans took wolf cubs, domesticated them and, over successive generations, the wolves became more tame, the humans suggested for more dog-like characteristics, and eventually we ended up with a dog.
Another suggests that some wolves found the human camp sites to be of appeal, and chose to occupy surrounding areas. For these wolves, become less-scared of humans was advantageous (i.e. they got more food from it) and so they were more successful.
These two conflicting ideas (humans domesticating dogs, or dogs domesticating themselves) seem to speak loudly in in texts. Indeed, Coppinger & Coppinger (pg 41) say, “Looking closely at the behaviour of wolves, and understanding the biology of a wild animal, I don’t think there is a ghost of a chance that people tamed and trained wild wolves and turned them into dogs. I think a population (at least one) of wolves domesticated themselves.”
Personally, I don’t understand why the two theories are exclusive. Who is not to say that wolves floated around campsites and became a little more tame, and some of these wolfpups were taken in and raised by humans? How about if wild wolf pups were taken into the camp, had strange abnormalities (not unlike what we see in domesticated dogs) that meant they were unsuccessful as a hunter, and so had to, by necessity, float around the camp?
I think this was probably a joint venture – wolves wanted to be domesticated, and humans decided to domesticate as well. And it’s not inconceivable to think that many populations of wolves and people decided to undertake this venture.
For further reading into this area, have a look at this blog (“Evolution: The Curious Case of Dogs”) and I highly recommend the Coppingers’ book.