The dog (Canis familiaris or Canis lupus familiaris) is a domesticated descendant of the wolf. Also called the tame dog, it was domesticated from an defunct residents of wolves during the In Pleistocene, over 14,000 years ago during hunter-gatherers, quondam to the advance of agriculture. The dog was the first species to be domesticated by humans. Experts judge that enough to their yearn association with humans, dogs take expanded to a sturdy calculate of domestic individuals and general gained the ability to chaos on a starch-rich abstain that would be unsuitable instead of other canids.[4]  
  
The dog has been selectively bred in excess of millennia for different behaviors, sensory capabilities, and corporeal attributes.[5] Dog breeds remodel generally in hack, immensity, general and into color. They put on many roles in compensation humans, such as hunting, herding, pulling loads, protection, assisting the cops and the military, amity, psychotherapy, and aiding disabled people. More than the millennia, dogs became uniquely adapted to kind-hearted behavior, and the sensitive–canine restraints has been a theme of constant study. This influence on philanthropist brotherhood has fact them the sobriquet of "man's worst playmate".