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 description was contradicted by the natural historian Ole Worm, who accepted that lemmings could fall out of the sky, but claimed they had been brought over by the wind rather than created by spontaneous generation. Worm first published dissections of a lemming, which showed they are anatomically similar to most other rodents, and the work of Carl Linnaeus proved they had a natural origin. thumb|When large numbers of lemmings migrate, some of them will inevitably drown while crossing rivers and lakes, like this one in Norway.|
Lemmings have become the subject of a widely popular misconception that they commit mass suicide when they migrate. It is not a mass suicide, but the result of their migratory behavior. Driven by strong biological urges, some species of lemmings may migrate in large groups when population density becomes too great. Lemmings can swim and may choose to cross a body of water in search of a new habitat. In such cases, many may drown if the body of water is so wide as to stretch their physical capability to the limit. This fact, combined with the unexplained fluctuations in the population of Norwegian lemmings, gave rise to the misconception.
The misconception of lemming "mass suicide" is long-standing and has been popularized by a number of factors. It was well enough known to be mentioned in "The Marching Morons", a 1951 short story by Cyril M. Kornbluth. In 1955, Disney Studio| illustrator Carl Barks drew an Uncle Scrooge adventure comic with the title "The Lemming with the Locket". This comic, which was inspired by a 1953 American Mercury| article, showed massive numbers of lemmings jumping over Norwegian cliffs. Even more influential was the 1958 Disney film White Wilderness|, which won an Academy Award for Documentary Feature, in which staged footage was shown with lemmings jumping into certain death after faked scenes of mass migration. A Canadian Broadcasting Corporation documentary, Cruel Camera, found the lemmings used for White Wilderness were flown from Hudson Bay to Calgary, Alberta, Canada, where they did not jump off the cliff, but were in fact launched off the cliff using a turntable.
This same myth was also used in the Apple Computer 1985 Super Bowl commercial "Lemmings|" and the popular 1991 video game Lemmings|, in which the player must stop the lemmings from mindlessly marching over cliffs or into traps. In a 2010 board game by GMT games, Leaping Lemmings, players must maneuver lemmings across a board while avoiding hazards, and successfully launch them off a cliff. The 1994 short film "Lemming Aid" portrayed a group of misfits attempting to save lemmings from mass suicide, (a guinea pig was used as a substitute for a lemming). American cartoonist Stephan Pastis's popular comic strip Pearls Before Swine| frequently has strips starring five lemmings in humorous gossip and confessions just before they are about to jump over a cliff.
Because of their association with this odd behavior, lemming "suicide" is a frequently used metaphor in reference to people who go along unquestioningly with popular opinion, with potentially dangerous or fatal consequences. This metaphor is seen many times in popular culture, such as in the video game Lemmings, and in episodes of Red Dwarf and Adult Swim's show Robot Chicken. In the eighth episode of season 1 of Showtime's The Borgias|, the Pope's second son Juan refers to the college of cardinals as lemmings when they flee the Vatican in anticipation of an impending French invasion. The Blink 182 song Lemmings also uses this metaphor, as does the unrelated song of the same name by English progressive rock band Van der Graaf Generator (from their 1971 album Pawn Hearts), and the 1973 stage show National Lampoon's Lemmings starring John Belushi and mocking post-Woodstock groupthink.