FROM THE FIRST DOMESTICATED CANINE 15,000 or more years ago, dogs have evolved into an incredible variety of shapes, sizes, and temperaments. Over the millennia, people have developed them to perform tasks ranging from hunting to herding to retrieving. Along the way, we have also set down guidelines as to how each type of dog should look and act. Here, you'll learn about the Labrador's appearance, temperament, and working ability.