Fur and Camouflage
Wolves can be found throughout some of the coldest regions on Earth, including Siberia, northern Canada and Greenland. These wolves have a thick coat with two layers of fur to help insulate them from the cold climates. The undercoat is a woolly covering made to retain heat, while the coarser, outer coat is made up of guard hairs that help shed water. The wolf's tail is long, thick and bushy; when lying down, the wolf can cover his face with his tail to help conserve warmth.
Most wolves have coloring that allows them to blend in with their surroundings. Fur can be shades of gray and brown, although wolves can range from pure white to solid black. Tan, light brown and mottled shades of these colors are not uncommon. The red wolves that inhabit more southern, temperate climates are commonly reddish-brown.
Hunting
Wolves have developed a complex social structure that allows them to hunt quickly and efficiently. Most wolf packs have between four and 15 members, including an alpha male and his mate, the alpha female. Packs hunt within a designated territory, as small as 50 square miles and as large as 1,000 square miles. Large, tough paws and an athletic build allow them to cover long distances, and an individual wolf can run as fast as 40 mph for up to 20 minutes.
With eyesight 20 times sharper than a human's and a sense of smell 100 times stronger, a pack of wolves can quickly home in on their prey and surround them. When hunting in a pack, a group of wolves weighing between 40 and 175 pounds each can easily take down large hoofed animals like elk and caribou. The wolf's jaws can grip with more than 500 pounds of pressure per square inch, and their teeth come together in a scissor grip.
Communication
Wolves have also developed a sophisticated form of communication. Their howls have a number of different meanings. Wolves are much more secure within the pack, and a wolf that has been separated will howl to pack members for attention. A howling pack will also deter any intruders into their territory, helping to keep their food sources safe from encroachment.
Much as with dogs, barks and body language have a number of meanings. Growling with pinned ears is a sign that an alpha is being challenged, while a submissive wolf will show its belly or tuck its tail between its legs. This reinforcement of the status of the strongest wolf helps ensure the survival of the pack, as the dominant members are not only the ones that give the orders.
Social Groups
The social hierarchy of the wolf pack is one that has been adapted in order to ensure efficient survival of the species. Within each pack there are an alpha male and female, who usually mate for life and are the only pair within the pack to breed. This means that the strongest couple reproduce to continue the species; it is this pair that eat first and get access to the choicest meat for their young. The wolf pups are an important part of the pack -- so important that the lower-ranking members of the pack will often take turns watching and caring for the pups while the alphas lead the hunt.
This social adaptation ensures that the pups born have the best chance for survival, and food is not wasted on weaker pups. With only the strongest reproducing, the pack is only responsible for the most promising of the young.