<P> "Man's best friend" is a common phrase about domestic dogs, referring to their millennia - long history of close relations, loyalty, and companionship with humans . The first recorded use of a related phrase is by Frederick the Great of Prussia . It was likely popularized by its use in a poem by Ogden Nash and has since become a common colloquialism . </P> <P> Before the evolution of wolf into dog, it is posited that humans and wolves worked together hunting game . Wolves were the superior tracker but humans were the superior killer; thus wolves would lead humans to the prey and humans would leave some of the meat to the wolves . This working relationship eventually led to the evolution of dogs, though there is controversy as to the exact nature of that transition . Some say wolves evolved naturally into dogs, wherein the wolf that worked best with humans slowly began to assimilate and pass their domesticated genes down . Others say that humans took wolf cubs and raised them to be domesticated . Either way, humans and dogs formed a working relationship . </P>

Where did the phrase a dog is a man best friend come from