A Friend That Goes Back a Way

A UCLA research team’s announcement last week that dogs may have been man’s best friend for more than 100,000 years has given scientists a big bone to chew on.

The traditional belief has been that dogs go back only about 14,000 years because that’s when skeletons first show features diverging significantly from those of the dog’s presumed ancestor, the gray wolf, and moving toward those of modern breeds. That figure also coincides with when humans started building walled towns, planting crops and mastering irrigation.

The UCLA study, however, persuasively challenges this assumption. Through a sophisticated analysis of DNA from 67 dog breeds, the study’s director, Robert K. Wayne, found that all modern dog breeds appear to descend from a domesticated wolf that lived beside humans as long as 135,000 years ago.

Archeologists’ excavation-based findings are increasingly being challenged by studies like UCLA’s, based on the newer science of molecular genetics. Many of these archeologists question Wayne’s conclusion, arguing that human ancestors of more than 50,000 years ago lacked the brainpower to truly domesticate dogs.

But “Blood Rites,” by biologist and social critic Barbara Ehrenreich, suggests humans may have needed dogs for a simpler reason: self-defense. While we like to think of “man as hunter,” the book shows that for most of Homo sapiens’ existence, he was more often the hunted. Humans, Ehrenreich writes, “were preyed on by animals that were initially far more skilled hunters than ourselves.”

So if Ehrenreich and Wayne are right, then it’s possible that early man may have cut a deal with wolf-dogs: Food scraps in return for fending off predators such as leopards and even other wolves. The dog may have been not only man’s best friend but his best defender as well.