Dogs changed and adapted over millions of years as members of the dog lineage gradually evolved into the wolf by growing longer, stronger legs and a shorter tail. This increased size led to greater strength and power to hunt food and escape predators. Today’s wolf and modern domestic dogs descend from early canids. Hesperocyon, an early dog or canid, was a small, active hunter with a long body and tail but short legs, and although it was one of the earliest members of the dog family, it looked more like a weasel or mongoose. Humans domesticated the wolf and bred canine varieties, linking early canids to modern-day dogs, and Hesperocyon is an ancestor of today’s dogs, "Man’s best friend."