Herds of musk oxen roam the treeless tundra of the Far North. Following closely are wolves, predators looking for a meal. The wolves are no match for the powerful adult musk oxen with their helmet-like horns. When the herd is threatened, the adults form a circle around their young to protect them. Musk oxen, with their long, thick hair, are built to survive the harsh arctic winters. But the wolves still watch the herd —for a calf that can’t keep up or an old musk ox too weak to survive.