Science & History
Print|Text Size: ||
The Wolf Who Stayed

But those Germans get in the way again. Bonn-Oberkassel, site of the consensus first fossil dog, is not a permanent settlement.

Trying to square genetic and archaeological dates, Peter Savolainen resurveyed the mitochondrial DNA of dogs and wolves, recalibrated the molecular clock and proposed in a paper in Science, November 22, 2002, that the dog originated in East Asia 15,000 to 40,000 years ago. It was a good try, but now it appears that his “40,000 years ago” date was more accurate. Also, the earliest known dog appears in Germany, not East Asia, a region to which other genetic evidence points as well.

In many ways, the dispute over dates and places is just a precursor for the debate over how that happened. Archaeologists and evolutionary biologists who want the first dogs to look like dogs have tended to argue that the transition is a result of a biological phenomenon called “paedomorphosis.” That basically means that the animal’s physical development is delayed relative to its sexual maturation. It produces dogs with more domed heads; shorter, broader muzzles; and overall reduced size and slighter build than a wolf. Accelerated physical development relative to sexual maturation (hypermorphosis), on the other hand, produces dogs larger than the progenitor wolf.

When maturation is stopped early enough, the resulting animal is said to resemble a “neotenic,” or perpetually juvenilized, wolf. Coppinger and others have carried the argument further to argue that behaviorally, the dog resembles a neotenic wolf, with some breeds being more immature or less developed than others. There is general agreement that, beginning in the late 19th century when the dog began to move into the city as a pet, breeders sought to soften and humanize the appearance of some breeds to make them look like perpetual puppies. But beyond that, it is more correct to view the dog as an entity different from the wolf.

Currently, many researchers like to invoke an experiment in domestication launched in 1959 at the Institute of Cytology and Genetics in Novosibirsk, Siberia, by Dmitry Belyaev and continued after his death by Lyudmila Trut and her colleagues. Belyaev selectively bred foxes for “tameness” alone, defined as their level of friendliness toward people. He ended up with foxes that resembled dogs. A number of them had floppy ears, piebald coats, curly tails and a habit of submissively seeking attention from their human handlers with whines, whimpers and licks. (I wouldn’t want such a dog.)

Anthropologist Brian Hare tested the tame foxes in 2004 and found that they, like dogs, had the capacity to follow a human’s gaze, something wolves and wild foxes, not to mention chimpanzees, won’t do.

A number of researchers have embraced these tame foxes as a template for dog domestication. While they doubtless cast insight on the problem, I doubt that they will answer all questions. Arguments by analogy are suspect science and should be even more so in this case, since the selection criteria for these foxes were also against aggression—hardly the case for dogs—and foxes clearly are not wolves.

That said, the experiment does appear to confirm that selective breeding for behavior alone can also produce morphological changes similar to what the wolf experienced in becoming a dog.

Coppinger has invoked the fox experiment to support his theory that wolves that became dogs self-domesticated. As humans in some areas moved into permanent settlements, their refuse heaps became feeding grounds for wolves who were tame enough—or least-frightened enough—to feed near humans. Subsequent generations became more tame, and people began to allow them to wander their camps, eating feces, hunting rodents. From that group, people took some animals for food. Then, when the animals were thoroughly self-tamed, people began to train them to more wolfish behaviors, like hunting.

What he and others overlook in citing the fox experiment is that those animals were subjected to intense artificial selection by people. They also ignore the fact that the first dog appears in a seasonal camp, not a permanent settlement.



Illustration by Amadeo Bachar

More From The Bark

Jane Brackman
Claudia Kawczynska
Claudia Kawczynska
More in Science & History:
Body Language
Is Your Dog Waiting For You?
Scientists Searching for Clues to The First Dog
The Wolf in Your Dog
Alexandra Horowitz, The Canine Mindseeker
DNA Testing
Can DNA Decipher the Mix?
Darwin’s Dogs