Managing mutations of a species: the evolution of dog breeding
(PHYSorg.com Biology)

In the first edition of On the Origin of Species, Charles Darwin mentions dogs 54 times. He does so mainly because the extraordinary variation between dog breeds provides a marvellous illustration of the power of selection. For most of the roughly 15,000 years since their domestication, dogs were selected by humans for their usefulness as hunters, retrievers, herders, guards or companions.