The human brain needs protein to function. For the early humans to survive and thrive they had to have meat in their diet. That is why the domestication of animals occured. Since all of this was happening waaay before the invention of firearms, who was better suited to help guard this prescious resource than man' best friend? When we play, or work, with our pooches we seem to forget the vital role the pooches played in human development. Now I will go and give my LGD a hug and a kiss.