Discusses the tundra ecosystem and the role of lemmings as a keystone species in helping to maintain it, describing the lemmings' place on the food chain and what would happen to the tundra if they were to become extinct.
Discusses the tundra ecosystem and the role of lemmings as a keystone species in helping to maintain it, describing the lemmings' place on the food chain and what would happen to the tundra if they were to become extinct.