Mimicry is an evolved resemblance between an organism and another object, often an organism of another species. The resemblances that evolve in mimicry can be visual, acoustic, chemical, tactile, or electric, or combinations of these sensory modalities. Mimicry may be to the advantage of both organisms that share a resemblance, in which case it is a form of mutualism; or mimicry can be to the detriment of one, making it parasitic or competitive. The evolutionary convergence between groups is driven by the selective action of a signal-receiver or dupe. Most known mimics are insects, though many other examples including vertebrates are also known. Plants and fungi may also be mimics, though less research has been carried out in this area.
Mimicry may involve the superficial resemblance of two or more organisms that are not closely related taxonomically. Although the best-known examples of mimicry involve similarity of appearance, investigations have disclosed fascinating cases in which the resemblance involves sound, smell, behavior, and even biochemistry. A key element in virtually every mimetic situation is deception by the mimic, perpetrated upon a third party, which mistakes the mimic for the model. This third party may be the collective potential predators upon the mimic, potential prey of a predacious mimic, or even one sex of the mimic’s own species. In some cases, such as host mimicry by parasites, the organism deceived is the model.
Mimicry is present in the natural world, and there are endless examples of both animals and plants that mimic other living creatures or inanimate objects, in a variety of different ways. One example is the monarch and viceroy butterflies. Another astonishing form of mimicry is Emsleyan or Mertensian mimicry, where a deadly prey mimics the warning signs of a less dangerous species. A good example involves the milk, coral, and false coral snakes. Both the harmless milk snake and the deadly coral snake mimic the warning signs of the moderately venomous false coral snake. One last form of mimicry is automimicry, which occurs within a single organism. It is when one part of an organism’s body resembles another part, like in a number of snake species that have tails that resemble their heads, and may even move backward when threatened.