The origin and evolution of the domestic dog remains a controversial question for the scientific community, with basic aspects such as the place and date of origin, and the number of times dogs were domesticated, open to dispute. Pugs and poodles may not look the part, but if you trace their lineages far enough back in time all dogs are descended from wolves. Gray wolves and dogs diverged from an extinct wolf species some 15,000 to 40,000 years ago.

But controversies abound concerning where a long-feared animal first became our closest domestic partner. Genetic studies have pinpointed everywhere from southern China to Mongolia to Europe. Scientists can only guess how dogs and humans first became friendly. Most likely, it was wolves that approached us, not the other way around, probably while they were scavenging around garbage dumps on the edge of human settlements.

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