The gray wolf is the largest wild member of the Canidae family and an ice-age survivor originating during the Late Pleistocene around 300,000 years ago. Due to habitat destruction, environmental change, persecution by humans, and other barriers to population growth, gray wolf populations are now found only in a few areas of the contiguous United States, Alaska, Canada, Mexico (a small population), and Eurasia.
Wolves can travel for long distances. They can cover several miles trotting at a pace of around 10 km/h, but they can reach speeds of up to 65 km/h during a chase. Wolf paws are able to tread easily on a wide variety of terrains. In particular, they have a slight webbing between each toe, which allows them to move over snow more easily.
Wolves are highly social. They live in packs and maintain a strict rank-oriented social hierarchy, which is led by the alpha male and the alpha female. Most alpha pairs are monogamous, but there are exceptions. Usually only the alpha pair is able to rear a litter, once a year, with the help of the rest of the pack.
The well-known howling of wolves helps pack members keep in touch, because it allows them to communicate in thickly forested areas or over great distances.
The arctic wolf (Canis lupus arctos, see picture below) is a subspecies of the gray wolf. It lives on the islands of the Canadian Arctic and the north coast of Greenland. This is maybe the least studied of all wolves, because its habitat is too harsh and remote for scientists to stay for long periods of time, mainly during the winter.
The above picture was taken at the Attica Zoological Park in Athens, Greece, in July 2008.
A picture of the white arctic wolf (still a subspecies of the gray wolf) follows.
Canis lupus arctos
The above picture of an arctic wolf was taken at the zoo of Berlin, Germany, in September 2005.
Life on Earth