Norway lemming, Lemmus lemmus
Lemmings in popular culture have been given the role of the blind follower due to the widespread myth that when migrating, the little rodents will follow one another so completely that they will follow other lemmings off a cliff in a mass suicide. Incredibly, this story was started by Disney with the film “Wild Wilderness” in 1958.
Lemming populations fluctuate dramatically in a cycles of four years, with populations exploding before dropping close to extinction. The population drops occur naturally (whether they are in response to weather fluctuations, food availability, or some other factor, scientists aren’t certain), but that wasn’t dramatic enough for the film or at all easy to portray, so the filmmakers herded lemmings over a small cliff into a river to create the fake suicide march. When populations get too dense and food is scarce, lemmings do migrate in large numbers, not en massed but in spread-out groups.(x)
Lemmings live in tundra biomes and feed on grass, sedge, shoots and other plant matter. They are most closely related to voles and muskrats. There are over 20 extant species; the Norway lemming and the Brown lemming are the two species with the most dramatic population explosions. Unlike other rodents, lemmings are conspicuously colored and will behave aggressively towards predators and even humans.(x)
The Norway lemming is found in the Fenno-Scandinavia region and is the only vertebrate native to the region. It is active both day and night, alternating naps with periods of activity. They spend the winter in nests under the snow. They migrate in the spring and autumn as changing weather makes certain areas uninhabitable. They will breed year-round when conditions are good.