The Grey Wolf (Gray Wolf in America) used to roam over much of northern Eurasia and America but its range is now much reduced.
It is the wild ancestor of all domestic dogs.
There are over 30 subspecies of Grey Wolf including the domestic dog (one subspecies; dog-wolf hybrids are fertile) and
the Australian Dingo (Canis lupus dingo).
The wolf shown above and immediately below is the nominate subspecies, the European Grey Wolf,
Canis lupus lupus.
It lives in social "packs" of family members and hunts as a coordinated pack.
The Canadian Timber Wolf above, also called Northwest Timber Wolf,
Canis lupus occidentalis, is the largest subspecies of wolf
and is native to forests of Alaska, western Canada and northwestern USA.
The Arctic Wolf, also called the Polar or White Wolf, Canis lupus arctos,
is a subspecies with thick white fur; it ranges across arctic Canada and Greenland.
The Red Wolf used to be classed as a separate species, Canis rufus,
then treated as a subspecies, Canis lupus rufus. It was then thought to be a hybrid population of Grey Wolf and Coyote
but is now considered an intermediate species. It was extinct in the wild by 1980 but has been reintroduced to North Carolina from captive-bred Red Wolves.
The Iberian Wolf, Canis lupus signatus,
ranges over north-western Spain and northern Portugal but is relatively rare. It is distinct from the extinct Spanish Wolf, Canis lupus deitanus.