Did you know that man's best friend is descended from wolves? Yep, all dogs — even your sister's Shih Tzu, Fluffy — can trace their family tree back to those big, powerful, sharp-toothed killing machines. According to DNA and fossil analysis, this transition from wild to domesticated happened somewhere between 15,000 and 30,000 years ago [source: Gorman]. But what exactly was it that moved wolves out of the woods and onto our sofas?
Scientists don't know for sure, but they have some guesses. One theory is that humans took an active role in the process, actually removing wolf pups from their parents and breeding them for tameness. Current thinking, however, suggests a more passive role. Tamer wolves were more likely to wander up to human encampments and scavenge out of our trash dumps. With such abundant food, these tame wolves reproduced prolifically until, after many generations, they produced the cuddly pets we know today [source: Gorman].
Whether humans actively fought the wild nature of wolves or passively let nature do the work, we did decide to let them stick around as pets. Now look into Fluffy's eyes and tell us that's not a win for humanity.