Is Domestication Genetic?

Beefs and Beliefs

Research in Siberia suggests humans breeding domestic animals sorted out a “different” phenotype.

Published on: April 19, 2011

The other day on a flight to South Carolina I read again about a long-running experiment in Siberia domesticating foxes and I think it taught me a little more about breeding beef cattle.

I first read about this research 15 or so years ago in Scientific American and found it as intriguing now as I did then. This new piece was in the March issue of National Geographic.

In brief, a researcher named Dmitry Belyaev noticed back in the 1950s that some silver foxes on a Siberian fur farm were more friendly and even dog-like in their attitude toward humans than were the majority of the population. He began a project to select those with the greatest friendliness and breed them together with the hope of exploring the concepts of how dogs and other animals became man-companions.

The result of this experiment has been increasing dog-like-ness and even greater friendliness in that line of foxes. They wag their tails when humans approach, bark and whine for attention, have droopy ears as babies, are capable of breeding any time during the year like dogs and unlike wild canids which can only breed once a year and usually during certain seasons. These latest generations are so friendly, the author says, they will leap into the arms of humans and lick their faces. A few have been allowed to go home with researchers or others to live successfully as family pets.

One supposition of the original researcher and of the lead researcher today, as well as the author, is this experiment could explain how “wolves” became the dogs of today. I’d suggest despite the genetic markers to that end that viewpoint is a little narrow and perhaps would be better stated that it could explain how many species of wild dogs across the world eventually became the domesticated dogs of today.

In this particular article the author says only certain animals appear to be domesticatable, which has always appeared to be true. Then he explains the researchers believe this tendency, or trait, is controlled by a potentially complex interaction of genes.

In fact, as the researchers have selected for a single trait they have found several phenotypic traits seem to accompany “domestic-ness.” Some of these are piebald color pattern, floppy ears as babies, tails that are shorter and curling upward.

At the same time they have bred one line of foxes for their love of humans they have successfully bred an opposite line for aggressiveness and dislike of humans.

Curiously, they have succeeded in doing roughly the same thing with rats and mink.

As I read the article I kept having a rush of thoughts and new ideas – too many to fully share here. But I’ll disclose a few.

I do not expect that all domestic creatures are necessarily genetically different than their forebearers, at least not as these foxes appear to be. Horses, for example, still strike me as being quite wild, although they can learn to tolerate and even trust humans. Sometimes I would make the same argument for cattle and certainly for domestic cats. It reminds me of records from early explorers’ journals when they entered Pacific islands no human seemed ever to have explored. They said none of the animals or birds were afraid of them. They had no genetic or learned experience with two-legged, hairless predators.

Although it is interesting that certain phenotypic features of “domesticated” animals seem relatively consistent, I’m not sure there’s a specific genetic link. Some researchers think the same thing.

We can’t know the condition of the animals at first contact with humans and no amount of research will ever do that. Neither will we ever know what the scores of species on this continent were like when humans first arrived and hunted them, perhaps to extinction. And we’ll likely never have the DNA to test those animals.

But as a person who takes a detailed interest and active part in the breeding of domestic animals, I find this fact especially fascinating: This project in Siberia shows once again that animals can be successfully linebred without collapsing into a pool of primordial genetic goo, as many today in the beef industry seem to think.