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Lemmings are small rodents, usually found in or near the Arctic, in tundra biomes.

Misconceptions about lemmings go back many centuries. In the 1530s, the geographer Zeigler of Strasbourg proposed the theory that the creatures fell out of the sky during stormy weather (also featured in the folklore of the Inupiat/Yupik at Norton Sound), and then died suddenly when the grass grew in spring.

This myth was refuted by the natural historian Ole Worm, who accepted that the lemmings could fall out of the sky but that they had been brought over by the wind rather than created by spontaneous generation.