|The green parts are where the wolves are right now,|
and the red parts are where they used to live.
Another thing wolves can do is they can make less blood flow close to their skin, which helps them save heat. Wolves' footpads are on kind of a separate heating system, so their feet stay just above the temperature where the tissues would start to freeze.
The idea that some people have about the wolf pack is based on packs of unrelated wolves in zoos. In this type of "pack," there is an alpha pair who mate and all the other wolves have to be subordinate and fight their way up to be the alpha. But in the wild, a pack is just a mated pair and their pups. As soon as the pups get old enough to have families of their own, they leave the pack. This might be anytime from 5 months of age to 5 years.