is a large canine native to Eurasia and North America. It is the largest extant member of Canidae, with males averaging 40 kg (88 lb) and females 37 kg (82 lb). On average, wolves measure 105–160 cm (41–63 in) in length and 80–85 cm (31–33 in) at shoulder height.
The wolf is also distinguished from other Canis species by its less pointed features, particularly the ears and muzzle. The wolf is nonetheless closely related enough to smaller Canis species, such as the coyote and the golden jackal, to produce fertile hybrids with them. The winter fur of a wolf is long and bushy and predominantly mottled gray, although nearly pure white, red and brown to black colours also occur. Up to 38 subspecies of wolf have been recognized including the domestic dog.
The wolf is the most specialized member of the genus Canis for cooperative big game hunting, as demonstrated by its physical adaptations to tackling large prey, its more social nature, and its highly advanced expressive behaviour. It travels in nuclear families consisting of a mated pair accompanied by their offspring. Offspring may leave to form their packs on the onset of sexual maturity and in response to competition within the pack for food. Wolves are also territorial and fights over territory are among the principal causes of wolf mortality packs. The wolf is mainly a carnivore and feeds primarily on large wild hooved mammals, though it also eats smaller animals, livestock, carrion, and garbage. Single wolves or mated pairs typically have higher success rates in hunting than do large packs. Various pathogens and parasites may infect wolves, notably rabies.
The global wolf population was estimated to be 300,000 in 2003 and is considered to be of Least Concern by the International Union for Conservation of Nature (IUCN). The wolf has a long history of interactions with humans, having been despised and hunted in most pastoral communities because of its attacks on livestock, while conversely being respected in some agrarian and hunter-gatherer societies. Although the fear of wolves exists in many human societies, the majority of recorded attacks on people have been attributed to animals suffering from rabies. Non-rabid wolves have attacked and killed people, mainly children, but this is rare because wolves are relatively few, live away from people, and have developed a fear of humans because of their experiences with hunters and shepherds.