In 1955, Disney Studio illustrator Carl Barks drew an Uncle Scrooge adventure comic with the title "The Lemming with the Locket". It was well enough known to be mentioned in "The Marching Morons", a 1951 short story by Cyril M. The misconception of lemming "mass suicide" is long-standing and has been popularized by a number of factors. This fact and the unexplained fluctuations in the population of Norwegian lemmings gave rise to the misconception. In such cases, many may drown if the body of water is so wide as to stretch their physical capabilities to the limit. They can swim and may choose to cross a body of water in search of a new habitat. Driven by strong biological urges, some species of lemmings may migrate in large groups when population density becomes too great. It is in fact not a mass suicide but the result of their migratory behavior. Lemmings have become the subject of a widely popular misconception that they commit mass suicide when they migrate by jumping off cliffs.
Worm first published dissections of a lemming, which showed that they are anatomically similar to most other rodents such as voles and hamsters, and the work of Carl Linnaeus proved that they had a natural origin. In the 1530s, geographer Zeigler of Strasbourg proposed the theory that the creatures fell out of the sky during stormy weather and then died suddenly when the grass grew in spring.This description was contradicted by natural historian Ole Worm who accepted that lemmings could fall out of the sky, but claimed that they had been brought over by the wind rather than created by spontaneous generation. Misconceptions about lemmings go back many centuries. The lemming defense system is thought to be based on aposematism (warning display).įor many years, the population of lemmings was believed to change with the population cycle, but now some evidence suggests their predators' populations, particularly those of the stoat, may be more closely involved in changing the lemming population. Lemmings, by contrast, are conspicuously colored and behave aggressively towards predators and even human observers. It is not known why lemming populations fluctuate with such great variance roughly every four years, before numbers drop to near extinction.Lemming behavior and appearance are markedly different from those of other rodents, which are inconspicuously colored and try to conceal themselves from their predators. The Norway lemming and brown lemming are two of the few vertebrates which reproduce so quickly that their population fluctuations are chaotic,rather than following linear growth to a carrying capacity or regular oscillations. Like many other rodents, lemmings have periodic population booms and then disperse in all directions, seeking the food and shelter their natural habitats cannot provide. They are solitary animals by nature, meeting only to mate and then going their separate ways, but like all rodents, they have a high reproductive rate and can breed rapidly when food is plentiful. They remain active, finding food by burrowing through the snow and using grasses clipped and stored in advance. Lemmings do not hibernate through the harsh northern winter. Like other rodents, their incisors grow continuously, allowing them to exist on much tougher forage than would otherwise be possible. At times, they will eat grubs and larvae. They are herbivorous, feeding mostly on leaves and shoots, grasses, and sedges in particular, but also on roots and bulbs. They generally have long, soft fur, and very short tails. Lemmings weigh from 30 to 110 g (1 to 4 oz) and are about 7 to 15 cm (3 to 6 in) long. They make up the subfamily Arvicolinae (also known as Microtinae) together with voles and muskrats, which forms part of the superfamily Muroidea, which also includes rats, mice, hamsters, and gerbils. A lemming is a small rodent usually found in or near the Arctic in tundra biomes.
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