It is man’s best friend… and also the oldest. The dog was the first animal we domesticated, at least fifteen thousand years ago, when we were still hunter-gatherers. Its ancestors were wolves that began to approach our camps. Since then it has been a herder, guardian, hunter, guide and companion. Its sense of smell is thousands of times more sensitive than ours, and it understands our gestures, such as pointing with a finger, even better than chimpanzees do. And the connection goes further: when a dog and a person look into each other’s eyes, both release oxytocin, the hormone of affection. Today there are hundreds of breeds around the world, from the tiny Chihuahua to the great mastiff. All of them share one thing: a history with us.