By “Sunday Morning” contributing videographer Judy Lehmberg.
Lyudmila Trut, an evolutionary geneticist at the Institute of Cytology and Genetics in Novosibirsk, Russia, has been studying domestication in foxes since 1959. Her mentor and friend, Dmitri Belyaev, began the study hypothesizing that all domesticated animals share one trait: tameness.
When their experiment began they had no idea how long it would take to get a tame fox. They carefully selected animals that showed the least fear or aggression towards humans and bred them. Remarkably, after only six generations of selecting for tameness, they saw fox puppies “that eagerly sought contacts with humans, not only [tail] wagging [but] also whining, whimpering, and licking in a dog-like manner.”
We can never know exactly how the first animals were domesticated, but from the fox experiments we know it may not have taken very long. We also know from both DNA testing and archeological finds that the wolf was the first animal to be domesticated, when dogs began appearing about 15,000 years ago. Wolves and dogs are still very closely related today, but they look and act differently.
A simplified scenario of how domestication might be: wolves were attracted to the smell of human food cooking; humans recognized what an asset a wolf might be; and the domestic dog was born. Humans acquired an early warning system for intruders as well as some protection from those intruders.
Those early wolf/dogs may have benefitted humans with their hunting ability as well. Because of DNA comparisons, we know very few traits separate wild foxes from domesticated ones, or wild wolves from domestic dogs.
The same is true for horses. There are about 125 genes that separate ancestral horses from their modern, domesticated cousins. Over the years there have been disagreements as to whether horse domestication happened several times or only…