In one of the first compelling examples of the impact global warming will have on nature and wildlife, Norway’s lemming population appears to be on the verge of a major population decline. Lemmings throughout Scandinavia have traditionally undergone natural population explosions every three to five years, causing hundreds of thousands of the animals to flood the land in search of food. But these reliable booms have become a rarity in most regions of Scandinavia, and climate change appears to be to blame. Norwegians used to get snowploughs out to clear their roads of the crushed lemmings during population bursts, but National Geographic News reports that southern Norway hasn’t seen a boom since 1994.