I think most people started a relationship with animals for utilitarian purposes. We domesticated various animals for food sources or to work. Latter, when we reached a level of advancement where the working/food source nautre of animals was not as common, other attachments began to form. This is an entirely different reason for why people, at least initially, took in animals. It wasn't evolutionary trickery, but more just evolutionary common sense. A dog has lots of uses, especially in a much more primative society. That man breed in intelligence and possibly the social nature of dogs maybe from a common sense approach as well. After all a dog too dumb not to realize it is supposed to protect the sheep vs. eating them is less valuable than one that does learn the difference. Same thing with other breeds of dogs and human aggression. In some breeds human aggression was bred out through selective breeding. This also made the dogs very friendly to humans. Unintended consequence? Maybe, but the idea that it is evlutionary trickery strikes me as the wrong way to think about it.

As such, I think the premise of the hypothesis is flawed. The conclusion may still be correct, but I'm not so sure. I'm far from convinced it is because dogs are merely "social parasites".

The idea that several thousand years ago humans took the domesticated dogs precusor, domesticated it, trained it, simply so we could have them dance when we came home from hunting and gathering is just…dumb.

Steve - I mostly agree with you, but also point out that humans do have a tendency to attach themselves to things that mimic human behavior to a point and let the human fill in the rest. Tamagatchis, for example. Or pet birds, say, which outside of hawks and falcons don't and didn't ever serve any real useful purpose. I don't think you can discount that entirely when considering the sum of our relationships with animals.

Fair points all. Ditto cats, which were great at killing disease bearing rodents.

Still, most of us now keep pets primarily for companionship, not utilitarian reasons.

The American Pit Bull Terrier was initially a "catch dog" for butchers several hundred years ago. They needed a dog that was tenacious and disregarded pain (dogmen call this gameness) that could hold a bull. Since those days the APBT has been used in a variety of ways. A pit bull will take down a fox or coyote with ease. Even a wolf would most likely come out on the short end of the stick against a pit bull. The dogs are also incredibly strong and fair well in weight pull competitions today, so a farmer in the past could use the dog to pull loads in a small cart that might not be suitable for a horse. And it is rare when an APBT wont defend its owner with the same level of gameness that it's ancestors had in going after bulls or other dogs.

Then there other dogs like retrievers and pointers who are useful when hunting. Dogs also have superior hearing and sense of smell, so using them for protecting livestock is also a benefit.

The idea that several thousand years ago humans took the domesticated dogs precusor, domesticated it, trained it, simply so we could have them dance when we came home from hunting and gathering is just...dumb. It doesn't even pass the giggle test. Dogs didn't inject themselves into our social system, we brought them in. That they have also turned out to be good companions as well as useful at work is just icing on the cake, IMO.