DogThe dog (Canis familiaris or Canis lupus familiaris) is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from extinct Pleistocene wolves, and the modern wolf is the dog's nearest living relative. Dogs were the first species to be domesticated by hunter-gatherers over 15,000 years ago before the development of agriculture. Due to their long association with humans, dogs have expanded to a large number of domestic individuals and gained the ability to thrive on a starch-rich diet that would be inadequate for other canids.
Dog breedA dog breed is a particular type of dog that was purposefully bred by humans to perform specific tasks, such as herding, hunting, and guarding. Dogs are the most variable mammal on Earth, with artificial selection producing around 450 globally recognized breeds. These breeds possess distinct traits related to morphology, which include body size, skull shape, tail phenotype, fur type, body shape, and coat colour. Their behavioral traits include guarding, herding, and hunting, and personality traits such as hyper-social behavior, boldness, and aggression.
Police dogA police dog is a dog that is trained to assist police and other law enforcement officers, search and rescue, or the military. Their duties may include searching for drugs and explosives, locating missing people, finding crime scene evidence, protecting officers and other people, and attacking suspects who flee from officers. The breeds most commonly used by law enforcement are the German Shepherd, Belgian Malinois, Bloodhound, Dutch Shepherd, and Labrador Retriever.
Dogs in warfareDogs in warfare have a very long history starting in ancient times. From being trained in combat, to their use as scouts, sentries, messengers, mercy dogs, and trackers, their uses have been varied and some continue to exist in modern military usage. War dogs were used by the Egyptians, Greeks, Persians, Sarmatians, Baganda, Alans, Slavs, Britons, and Romans. Among the Greeks and Romans, dogs served most often as sentries or patrols, though they were sometimes taken into battle.
