During the course of domestication, evolution worked on dog genes to adapt them for life with humans. Since then, humans have taken a greater hand. Even before genetics was established as a science, humans had been shaping the size, colour and temperament of their pets through selective breeding.
Science is still interested in the genetics of dogs, especially dog behaviour. A recent study carried out by Scottish scientists led to the discovery that the ability to fetch shows strong inheritance from parents to pups.