Mimicry is a physical or behavioral resemblance of one species to another, or to an inanimate object. Although it is more common in animals, it is also found in plants. This arrangement benefits either the originator only, or both species. Mimicry was first reported in 1862 by the British naturalist Henry Bates while observing tropical forest butterflies in Brazil. He described a resemblance between two unrelated families of butterflies, where the one family that was edible (mimic) closely resembled another inedible family (model). This is now known as Batesian mimicry. This type of arrangement confers an advantage to the mimic when predators such as birds (known as dupes) avoid the edible along with the unpalatable individuals. The original model species is argued to have evolved a warning coloration to advertise its distastefulness to potential predators. Natural selection favors palatable species that have evolved similar coloration. Thus, predation on both groups is diminished.
A familiar example in North America is the close resemblance between non-toxic Viceroy butterflies and distasteful Monarch butterflies, which obtain their toxin from the milkweed plant that the larval stage ingests. Both Viceroy and Monarch butterflies have prominent orange-colored wings with white spots and black venation, and are even difficult for humans to distinguish. Another example of Batesian mimicry is the resemblance of harmless king snakes to the venomous coral snakes, which both have red, yellow, and black bands. The red and black bands adjoin in the former, whereas the red and yellow bands are next to each other in the latter species.
A second type of mimicry is known as Mullerian, originating with the work of the German zoologist Fritz Muller in 1879. This type of mimicry differs from Batesian in that the two unrelated species that closely resemble each other are both unpalatable. An example of this is the close resemblance of the yellow and black color banding in many different species of stinging wasps. This strategy of "pooling" their adaptations reinforces the learning behavior of vertebrate predators such as birds to avoid all individuals that resemble these wasps. Recent research has suggested that the Viceroy-Monarch example may in fact be Mullerian because some birds find the Viceroy to be unpalatable. Another type of mimicry is orchids that possess floral structures that mimic female wasps to entice male wasps to land and attempt to mate, and in the process transfer pollen. The eye spots on butterfly and moth wings and the fake rattle behavior in some non-venomous snakes are further examples of mimicry that help protect these animals from predators. Mimicry differs from cryptic coloration (blending in with the environment) in that the bright coloration or distinctive behavior broadcasts an obvious message to would-be predators.
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