Where Did Dogs First Become Man's Best Friend?

Scientists trying to determine where dogs were first domesticated have been sent back to the drawing board by a new study. Back in 2002, researchers sampled DNA from dogs around the world, and determined that dogs in East Asia had the most genetic diversity, suggesting that the species originated there and that dogs in that region have had the longest time to evolve. But the new study suggests that those earlier results were skewed, because DNA sampling of African street dogs has revealed equal genetic diversity. The earlier findings may have been thrown off because the large-scale study included both purebred dogs, whose evolution has been closely guided by human hands, and street dogs, who have bred more autonomously and randomly, and who therefore show more genetic diversity. But the 2002 researchers drew DNA from different types of dogs in different regions. Says Adam Boyko, lead researcher of the new study: