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A mimic is any species that has evolved to appear similar to another successful species or to the environment in order to dupe predators into avoiding the mimic, or dupe prey into approaching the mimic^[1]. A mimic generally resembles its target in one or more of the following: appearance, behavior, and habitat. The capacity to mimic is sometimes called "mimetism." Mimetism differs from camouflage in that the mimic does not try to blend with the surroundings, but to appear as some other creature.

Contents 1 Types of mimicry 2 Examples 2.1 Batesian mimicry 2.2 Müllerian mimicry 2.3 Mertensian mimicry 2.4 Peckhamian mimicry 2.5 Bakerian mimicry 2.6 Vavilovian mimicry 2.7 Automimicry 3 Mimicry and convergent evolution 4 References

Many types of mimicry have been described:

1. Batesian mimics (named after Henry Walter Bates), where the mimic resembles the successful species but does not share the attribute that discourages predation.
2. Müllerian mimics (named after Fritz Müller), where the mimic resembles the successful species and shares the anti-predation attribute (dangerous or unpalatable.)
3. Mertensian mimics (named after Robert Mertens), often considered a subtype of Müllerian mimicry, where harmless and deadly mimics resemble a dangerous but not usually deadly species (if the predator dies, it cannot learn to recognize a trait, e.g. a warning coloration).
4. Peckhamian mimics (named after E. G. Peckham; also called Aggressive mimicry), where the mimic resembles a harmless species in order to lure prey.
5. Bakerian mimics (named after Herbert G. Baker), where the mimic resembles members of its own or other species in order to lure pollinators or reap other benefits, although the mimicry may not be readily apparent due to the fact that the members of the same species may still exhibit sexual dimorphism.
6. Vavilovian mimics (named after Nikolai Ivanovich Vavilov), where the mimic through generations of artificial selection comes to resemble a domesticated plant and may eventually be domesticated itself. This type of mimicry does not occur in ecosystems unaltered by humans.
7. Automimicry where the mimic has some part of its body resembling some other part. Examples include snakes in which the tail resembles the head and show behavior such as moving backwards to confuse predators and insects and fishes with eyespots on their hind ends to resemble the head. The term is also used when the mimic imitates other morphs within the same species such as some males looking like females or vice versa.

• Butterflies
  • The Ash Borer (Podosesia syringae), a moth of the Clearwing family (Sesiidae), is a Batesian mimic of the Common wasp because it resembles the wasp, but is not capable of stinging. A predator that has learned to avoid the wasp would similarly avoid the Ash Borer.
  • Plain Tiger (Danaus chrysippus) - an unpalatable model with a number of mimics.
  • Common Indian Crow (Euploea core) - an unpalatable model with a number of mimics. See also under Müllerian mimicry below.
  • Consul fabius and Eresia eunice imitate unpalatable Heliconius butterflies such as H. ismenius (Pinheiro 1996).
  • Owl butterflies (genus Caligo) bear eye-spots on the underside of their wings; if threatened, they turn upside-down on a twig and show their undersides to the predator (usually small birds or lizards); in this position, they resemble [1] an owl (such as the Short-eared Owl or the Tropical Screech Owl) for which in turn the butterfly predator would be food.
  • Several palatable butterflies resemble different species from the highly noxious papilionine genus Battus (Pinheiro 1996).

• The False Cobra (Malpolon moilensis) is a mildly venomous but harmless colubrid snake which mimics the characteristic "hood" of an Indian cobra's threat display. The Eastern Hognose Snake (Heterodon platirhinos) similarly mimics the threat display of poisonous snakes.

• Octopuses of the genus Thaumoctopus (the Mimic Octopus and the "wunderpus") are able to intentionally alter their body shape and color so that they resemble dangerous sea snakes or lionfish.

• Some believe that the female Congo Peafowl mimics the venomous Bush Vipers that also live in its habitat in terms of patterns (greenish brown) and behavior (the female rattles her quills and hisses like a snake).

• Butterflies
  • The Monarch butterfly (Danaus plexippus) is a member of a Müllerian complex with the Viceroy butterfly (Limenitis archippus) in shared coloration patterns and display behavior. This example was long believed to be a case of Batesian mimicry, with the Viceroy being the mimic and the Monarch the model, but it was more recently determined that the Viceroy is actually the more unpalatable species of the pair^{[citation needed]}. The Viceroy has three geographic races with somewhat different coloration, each one very closely matching the local Danaus species (e.g., in Florida, the pairing is of the Viceroy and the Queen, and in Mexico, the Viceroy resembles the Soldier). Therefore, the Viceroy is a single species involved in three different Müllerian pairs.
  • Unpalatable Euploea species look very similar. See also under Batesian mimicry above.
  • The genus Morpho is palatable but are very strong fliers; birds - even species which are specialized for catching butterflies on the wing - find it very hard to catch them. The conspicuous blue coloration shared by most Morpho species seems to be a case of Müllerian mimicry (Pinheiro 1996).
  • The "orange complex" of species, including the heliconiines Agraulis vanillae, Dryadula phaetusa, and Dryas iulia which all taste bad.^[2]

• various bees and numerous vespid and sphecoid wasps: These animals are examples of Müllerian mimics because they have the aposematic yellow and black stripes (sometimes black and red, or black and white). All are potentially harmful to predators, fulfilling the second requirement of Müllerian mimicry.

• Some Milk Snake (Lampropeltis triangulum) subspecies (harmless), the moderately toxic False Coral Snakes (genus Erythrolamprus), and the deadly Coral Snakes all have a red background color with black and white/yellow stripes. In this system, both the milk snakes and the deadly coral snakes are mimics, whereas the false coral snakes are the model.

• Female fireflies of the genus Photuris copy the light signals of other species, thereby attracting male fireflies which are then captured and eaten.

• The Alligator Snapping Turtle (Macrochelys temminckii) is a well-camouflaged ambush predator. Its tongue bears a conspicuous pink extension that resembles a worm and can be wriggled around; fish that try to eat the "worm" get in turn eaten by the turtle.

• Common in many species of Caricaceae. Their flowers have little or no nectar but resemble nectar-producing flowers. Pollinators will be fooled into visiting them and thus fertilization is ensured without having to produce a reward for the pollinator.

• Echinochloa oryzoides is a species of grass which is found as a weed in rice (Oryza sativa) fields. The plant looks similar to rice and its seeds are often mixed in rice and difficult to separate. This close similarity was enhanced by the weeding process which is a selective force that increases the similarity of the weed in each subsequent generation.

• Many insects have filamentous "tails" at the ends of their wings which are combined with patterns of markings on the wings themselves to create a "false head" which misdirects predators (e.g., hairstreak butterflies).
• Several pygmy owls bear "false eyes" on the back of their head to fool predators into believing the owl is alert to their presence.
• The female-colored males of the Common Side-blotched Lizard which use their mimicry to assist them in mating.

It is commonly assumed that mimicry evolves as a positive adaptation; that is, the mimic gains fitness via convergent evolution which results in resemblance to another species. However, there a few who believe such evolution is non-adaptive or merely a result of structural similarities, e.g., the lepidopterist (and sometime author) Vladimir Nabokov argued that much of insect mimicry, including the Viceroy/Monarch mimicry, resulted from the fact that coloration patterns in both species simply had a common structural basis, and thus the tendency to convergence by chance was very high.[2] However, this very example provides evidence precisely to the contrary, as the viceroy's color pattern is completely unlike any of the species to which it is closely related, and the viceroy itself has three color forms, each adapted to resemble a different species of Danaus. Likewise, this example is based on two organisms that are indeed fairly similar in structure (both butterflies), while a great many cases of mimicry (especially in large Batesian/Mũllerian complexes) involve insects from multiple orders that share virtually no structural similarities whatsoever (e.g., beetles, true bugs, moths, wasps, bees, and flies may all belong to a single mimetic complex, despite profound differences^[1]).

1. ^ ^{a b} Wickler, W. 1968. Mimicry in plants and animals. McGraw-Hill, New York
2. ^ Pinheiro, Carlos E. G. (1996) Palatablility and escaping ability in Neotropical butterflies: tests with wild kingbirds (Tyrannus melancholicus, Tyrannidae). Biol. J. Linn. Soc. 59(4): 351–365. HTML abstract

Topics in evolutionary ecology v • d • e
Patterns of evolution: Convergent evolution • Evolutionary relay • Parallel evolution
Colour and shape: Aposematism • Mimicry • Crypsis
Interactions between species: Mutualism • Cooperation • Predation • Parasitism