Dogs have been companions to humans for a long time. It is likely they were the first animal domesticated. There is a great deal of speculation about how dogs became dogs. We know that the dog started as a grey wolf, but since the change from wolf to dog happened in our distant past, we have very little to go on.
One theory is that wolf cubs were “adopted” by humans. This theory points out that our dogs exhibit the behavior of juvenile wolves. They have similar bark patterns and they wag their tails. Later they were bred for those behaviors and for other more juvenile wolf appearances.
A scientist in Russia, who was trying to breed fur animals that were easier to handle, started an experiment on domestication. He postulated that dog-like behavior could be bred for. For more than fifty years, Dmitri Belyaev led a project at The Institute of Cytology and Genetics at Novosibirsk that selectively bred silver foxes for the characteristic of being friendly with humans.
Over 35 generations, breeding for this one trait provided interesting physical results. The foxes that were bred for friendliness to humans, had shorter muzzles. Their coat color changed. The foxes came into heat every six months, instead of annual. The list of changes that came from simply breeding for tameness is amazing. And all of this happened over fifty years.
More surprising, after a mere six generations wanted attention from humans. They whined and licked hands, just like a dog. Mind you, these foxes were only tested for these interactions once a month. Otherwise, they were kept in cages as they were bred. Just imagine, though, six generations and the foxes were demonstrating all the characteristics we expect from our dogs.
At this point, very few of the foxes exhibited those traits. By the twentieth generation, thirty five percent did. According to the Institute now, more than seventy percent exhibit these domesticated traits.
Research has show that the bred foxes have a longer period of time before certain stress hormones peak, which means that they have a longer period of time before they react to unknown stimuli with a fear response. It is therefore easier to integrate them with humans. There is also an overall decrease in adrenal activity. The foxes are less inclined to have those fear responses.
Not all of these changes are promising results. For one thing, while the vixens do come into heat every six months, not pup born out of season (not during the usual annual breeding cycle of January to March) has survived to adult hood.
Domestic foxes are not dogs and not all of their domestic behavior is dog like. They are said to be as friendly as dogs but as independent as cats.
What else could come of this? We may never know. The domesticated breeding experiment is in constant jeopardy due to funding issues. They keep themselves afloat by selling some stock to fur breeders who are looking for animals more content with captivity and selling others as pets.
You can purchase a domesticated silver fox from SibFox. They’re expensive, but they have to be shipped from Russia. An animal domesticated under fairly rigorous scientific conditions. It is amazing to think about and consider how quickly an animal could be breed to fit in with humans.
Not all animals could be domesticated in this way, but it provides us insight into how man’s best friend became that.