Dogs have long been dependable companions by our sides. But it wasn’t always that way, and a look at their closest living relative, the wolf, makes it clear why. Research into dog domestication and intelligence offers clues into the human-dog relationship. And analyzing dogs’ brain activity and genes may even help answer whether dogs are in it for the food—or if they really love us.。挖酷网（vaacoo.com）提供手机在线免费在线观看狗的故事致力于为观众带来优质的观影体验！