Dog breeds are dogs that have relatively uniform physical characteristics developed under controlled conditions by humans, with breeding animals selected for phenotypic traits such as size, coat color, structure, and behavior. The Fédération Cynologique Internationale recognizes 337 pure dog breeds. Other uses of the term breed when referring to dogs may include pure breeds, cross-breeds, mixed breeds and natural breeds.
If you do not have time to exercise your dog daily with a brisk walk and lots of running choose a breed that does not have high exercise requirements. All of the breeds who require high amounts of exercise make terrific jogging, hiking, and ridding companions. So if you want your dog to accompany you on long runs choose one of these highly active breeds built for endurance and as much exercise as you can throw at them - they will love you for it (and a tired dog is not destructive).
If you do not like loose dog hair and do not want to be vacuuming the house every day, then do not buy a high shedding breed. If you own a high shedding dog you will find hair everywhere! Including on your clothes, on your furniture, in your bed, and even in your food. Additionally dogs that have a high shedding rate need to be brushed more often to brush out the dead hair.
The study found distinct genetic clusters within modern dogs that largely corresponded to phenotype or function. These included spitz-breeds, toy dogs, spaniels, Mastiff-like breeds, small terriers, retrievers, herding dogs, scent-hounds, and sight-hounds. There were 17 breeds that conflicted with phenotype or function and these were thought to be the result of crossing some of the other phenotypes. As in a 2004 study that found 9 ‘ancient breeds’ to be genetically divergent, the study found 13 breeds that were genetically divergent from the modern breeds: the Basenji, Saluki, Afghan hound, Samoyed, Canaan dog, New Guinea singing dog, dingo, Chow Chow, Chinese Shar Pei, Akita, Alaskan malamute, Siberian husky and American Eskimo dog. Results also indicated that the Basenji had recent admixture with Middle Eastern wolves.