Dog Calendars: Dogs can be your most faithful and loyal friends. What they expect from you in return is just that you feed them good food, shelter and take care of them. This selection of 2018 Dog Calendars feature dog breeds available around the world. Breeding for appearance was introduced in the 19th century. Up to that time, dog breeding concentrated on producing traits that were useful or work: vermin hunting (terriers), flushing and driving game (pointers, hounds), running down large and small quarry (mastiffs, greyhounds), and guarding (mastiffs). Characteristics such as size, color, or set of tail can he introduced or altered by breeding from animals with those traits. It is also possible to introduce a feature from another breed-for example, Dingo blood added to the Smooth-coated Collie to produce the Australian Kelpie-and then to breed across enough generations for the trait to run "true." 2018 Dog Breed Calendars make great gifts.