Mimicry

Mimicry, physical or behavioral resemblance of one species to another to benefit itself or, in effect, sometimes both species. By mimicking the color bands and buzzing sounds of stinging bees, for example, several species of otherwise defenseless moths and flies avoid predation by birds. The animal or plant being mimicked is usually an abundant species whose noxious characteristics have left a lasting impression on predators. Instead of avoiding detection by predators through camouflage, the mimicking species displays the same conspicuous warning marks or behavior as the harmful species.

Mimicry was discovered in 1862 by the British naturalist Henry Walter Bates, who found two similarly marked but unrelated families of Brazilian forest butterflies. Noting that one family was poisonous to birds, he explained that the palatable butterflies had survived by evolving similar warning markings. This concept, Batesian mimicry, was used to demonstrate Charles Darwin's theory of natural selection, whereby birds were seen to act as selective agents by eliminating the palatable butterflies that had fewer resemblances to the poisonous butterflies. Another kind of mimicry, called Müllerian mimicry, is found especially among insect species that are all similarly poisonous but that have evolved similar markings to reduce mortality. Instead of individual insect species developing distinct warning marks and sacrificing members to teach birds to avoid them, many species have subsequently evolved a common warning mark so that birds need learn but one lesson to avoid the entire group.

Mimicry occurs among a great many different forms of plants and animals, including orchids and insects, songbirds and hawks, and lizards and noxious beetles.