Mimic
Encyclopedia
Visual appearance
The visual appearance of objects is given by the way in which they reflect and transmit light. The color of objects is determined by the parts of the spectrum of light that are reflected or transmitted without being absorbed...
, behaviour, sound
Sound
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...
, scent and even location
Location (geography)
The terms location and place in geography are used to identify a point or an area on the Earth's surface or elsewhere. The term 'location' generally implies a higher degree of can certainty than "place" which often has an ambiguous boundary relying more on human/social attributes of place identity...
, with the mimics found in similar places to their models.
Mimicry occurs when a group of organisms, the mimics, evolve
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
to share common perceived
Perception
Perception is the process of attaining awareness or understanding of the environment by organizing and interpreting sensory information. All perception involves signals in the nervous system, which in turn result from physical stimulation of the sense organs...
characteristics with another group, the models. The evolution is driven by the selective
Selection
In the context of evolution, certain traits or alleles of genes segregating within a population may be subject to selection. Under selection, individuals with advantageous or "adaptive" traits tend to be more successful than their peers reproductively—meaning they contribute more offspring to the...
action of a signal-receiver, or dupe. For example, birds that use sight to identify palatable insects (the mimics), whilst avoiding the noxious models.
Collectively, this situation is known as a mimicry complex. The model is usually another species except in cases of automimicry. The signal-receiver is typically another intermediate organism like the common predator of two species, but may actually be the model itself, such as a moth resembling its spider predator. As an interaction
Biological interaction
Biological interactions are the effects organisms in a community have on one another. In the natural world no organism exists in absolute isolation, and thus every organism must interact with the environment and other organisms...
, mimicry is in most cases advantageous to the mimic and harmful to the receiver, but may increase, reduce or have no effect on the fitness
Fitness (biology)
Fitness is a central idea in evolutionary theory. It can be defined either with respect to a genotype or to a phenotype in a given environment...
of the model depending on the situation. Models themselves are difficult to define in some cases, for example eye spots may not bear resemblance to any specific organism's eyes, and camouflage often cannot be attributed to a particular model.
Camouflage
Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...
, in which a species resembles its surroundings, is essentially a form of visual mimicry. In between camouflage and mimicry is mimesis, in which the mimic takes on the properties of a specific object or organism, but one to which the dupe is indifferent. The lack of a true distinction between the two phenomena can be seen in animals that resemble twigs, bark, leaves or flowers, in that they are often classified as camouflaged (a plant constitutes its "surroundings"), but are sometimes classified as mimics (a plant is also an organism).p51 Crypsis
Crypsis
In ecology, crypsis is the ability of an organism to avoid observation or detection by other organisms. It may be either a predation strategy or an antipredator adaptation, and methods include camouflage, nocturnality, subterranean lifestyle, transparency, and mimicry...
is a broader concept which encompasses all forms of avoiding detection, such as mimicry, camouflage, hiding etc.
Though visual mimicry is most obvious to humans, other senses such as olfaction
Olfaction
Olfaction is the sense of smell. This sense is mediated by specialized sensory cells of the nasal cavity of vertebrates, and, by analogy, sensory cells of the antennae of invertebrates...
(smell) or hearing
Hearing (sense)
Hearing is the ability to perceive sound by detecting vibrations through an organ such as the ear. It is one of the traditional five senses...
may be involved, and more than one type of signal
Signalling theory
Within evolutionary biology, signalling theory is a body of theoretical work examining communication between individuals. The central question is when organisms with conflicting interests should be expected to communicate "honestly"...
may be employed. Mimicry may involve morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
, behavior
Behavior
Behavior or behaviour refers to the actions and mannerisms made by organisms, systems, or artificial entities in conjunction with its environment, which includes the other systems or organisms around as well as the physical environment...
, and other properties. In any case, the signal always functions to deceive the receiver by preventing it from correctly identifying the mimic. In evolutionary terms, this phenomenon is a form of co-evolution
Co-evolution
In biology, coevolution is "the change of a biological object triggered by the change of a related object." Coevolution can occur at many biological levels: it can be as microscopic as correlated mutations between amino acids in a protein, or as macroscopic as covarying traits between different...
usually involving an evolutionary arms race
Evolutionary arms race
In evolutionary biology, an evolutionary arms race is an evolutionary struggle between competing sets of co-evolving genes that develop adaptations and counter-adaptations against each other, resembling an arms race, which are also examples of positive feedback...
.p161 It should not be confused with convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
, which occurs when species come to resemble one another independently by adapting
Adaptation
An adaptation in biology is a trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation....
to similar lifestyles.
Mimics may have different models for different life cycle
Biological life cycle
A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...
stages, or they may be polymorphic
Polymorphism (biology)
Polymorphism in biology occurs when two or more clearly different phenotypes exist in the same population of a species — in other words, the occurrence of more than one form or morph...
, with different individuals imitating different models. Models themselves may have more than one mimic, though frequency dependent selection
Frequency dependent selection
Frequency-dependent selection is the term given to an evolutionary process where the fitness of a phenotype is dependent on its frequency relative to other phenotypes in a given population. In positive frequency-dependent selection the fitness of a phenotype increases as it becomes more common...
favors mimicry where models outnumber mimics. Models tend to be relatively closely related
Common descent
In evolutionary biology, a group of organisms share common descent if they have a common ancestor. There is strong quantitative support for the theory that all living organisms on Earth are descended from a common ancestor....
organisms, but mimicry of vastly different species is also known. Most known mimics are insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, though many other animal mimics including mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s are known. Plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s and fungi may also be mimics, though less research has been carried out in this area.
Etymology
Use of the word mimicry dates back to 1637. It is derivedEtymology
Etymology is the study of the history of words, their origins, and how their form and meaning have changed over time.For languages with a long written history, etymologists make use of texts in these languages and texts about the languages to gather knowledge about how words were used during...
from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
term mimetikos, "imitative," in turn from mimetos, the verbal adjective of mimeisthai, "to imitate." Originally used to describe people, it was only applied to other forms of life after 1851.
Classification
Many types of mimicry have been described. An overview of each follows, highlighting the similarities and differences between the various forms. Classification is often based on functionFunction (biology)
A function is part of an answer to a question about why some object or process occurred in a system that evolved through a process of selection. Thus, function refers forward from the object or process, along some chain of causation, to the goal or success...
with respect to the mimic (e.g. avoiding harm). Some cases may belong to more than one class, e.g. automimicry and aggressive mimicry are not mutually exclusive, as one describes the species relationship between model and mimic, while the other describes the function for the mimic (obtaining food).
Defensive
Batesian
The Wolf in Sheep's Clothing
A Wolf in Sheep's Clothing is an idiom of Biblical origin. It is used of those playing a role contrary to their real character, with whom contact is dangerous. As a fable it has been falsely credited to Aesop and the theme is now numbered 451 in the Perry Index...
. It is named after Henry Walter Bates
Henry Walter Bates
Henry Walter Bates FRS FLS FGS was an English naturalist and explorer who gave the first scientific account of mimicry in animals. He was most famous for his expedition to the Amazon with Alfred Russel Wallace in 1848. Wallace returned in 1852, but lost his collection in a shipwreck...
, an English naturalist whose work on butterflies in the Amazon rainforest
Amazon Rainforest
The Amazon Rainforest , also known in English as Amazonia or the Amazon Jungle, is a moist broadleaf forest that covers most of the Amazon Basin of South America...
(including Naturalist on the River Amazons) was pioneering in this field of study. Mimics are less likely to be found out when in low proportion to their model, a phenomenon known as negative frequency dependent selection which applies in most other forms of mimicry as well. This is not the case in Müllerian mimicry however, which is described next. Examples:
- LepidopteraLepidopteraLepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
- The Ash BorerAsh BorerThe Ash Borer , aka Lilac Borer, is a clearwing moth in the family Sesiidae. It is found throughout the United States east of the Rocky Mountains...
(Podosesia syringae), a moth of the Clearwing family (SesiidaeSesiidaeThe Sesiidae or clearwing moths are family of the Lepidoptera in which the wings partially have hardly any of the normal lepidopteran scales, leaving them transparent. The bodies are generally striped with yellow, red or white, sometimes very brightly, and they have simple antennae...
), is a Batesian mimic of the Common waspCommon waspThe common wasp, Vespula vulgaris, known in the US as the yellowjacket, is found in much of the Northern Hemisphere and has been introduced to Australia and New Zealand. It is a eusocial vespid which builds its grey paper nest in or on a structure capable of supporting it...
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 Crow (Euploea core) – an unpalatable model with a number of mimics. See also under Müllerian mimicry below.
- Consul fabiusConsul fabiusConsul fabius, common name Tiger Leafwing, is the most common and well known species of the genus Consul belonging to the Nymphalidae family, Charaxinae subfamily.-Description:...
and Eresia eunice imitate unpalatable HeliconiusHeliconiusHeliconius comprise a colorful and widespread brush-footed butterfly genus distributed throughout the tropical and subtropical regions of the New World. These butterflies utilize Passion flower plants as their larval food source and rely on bright wing color patterns to signal their distastefulness...
butterflies such as H. ismeniusHeliconius ismeniusHeliconius ismenius, also called the Ismenius Tiger or Tiger Heliconian, is a butterfly found in Central America and northern South America. They are highly populous as south as Ecuador and Venezuela and as north as southern Mexico, Guatemala and Belize. The H. ismenius are more commonly called...
. - Several palatable butterflies resemble different species from the highly noxious papilioninePapilioninaePapilioninae is a subfamily of the butterfly family Papilionidae. Papilioninae occurs world wide with most of the species being found in the tropics. There are roughly 480 species, of which 27 occur in North America.-References:...
genus BattusBattus (butterfly)Battus is a New World genus of butterflies that are usually found around pipevine plants. The caterpillars feed off the poisonous pipevines, making the insects poisonous themselves; they taste very bad to ward off predators. Since birds avoid these butterflies, other swallowtail species mimic...
. - Several palatable moths produce ultrasonic click calls to mimic the unpalatable tiger moths.
- The Ash Borer
- The False CobraFalse CobraThe false cobra is an opisthoglyphous snake found in parts of Africa and the Middle East. The name "False Cobra" comes from the fact that this is not a cobra. It imitates a cobra's stance by spreading its neck into a hood and hissing like the cobra...
(Malpolon moilensis) is a mildly venomous but harmless colubridColubridA colubrid is a member of the snake family Colubridae. This broad classification of snakes includes about two-thirds of all snake species on earth. The earliest species of the snake family date back to the Oligocene epoch. With 304 genera and 1,938 species, Colubridae is the largest snake family...
snake which mimics the characteristic "hood" of an Indian cobraIndian CobraIndian Cobra or Spectacled Cobra is a species of the genus Naja found in the Indian subcontinent and a member of the "big four", the four species which inflict the most snakebites in India. This snake is revered in Indian mythology and culture, and is often seen with snake charmers...
's threat display. The Eastern Hognose SnakeEastern Hognose SnakeThe Eastern Hognose Snake is a harmless colubrid species found in North America. No subspecies are currently recognized.-Geographic range:...
(Heterodon platirhinos) similarly mimics the threat display of venomous snakes.
- The milk snakeMilk SnakeThe milk snake or milksnake is a species of king snake. There are 25 subspecies among the milk snakes, including the commonly named scarlet kingsnake...
resembles the deadly coral snakeCoral snakeThe coral snakes are a large group of elapid snakes that can be subdivided into two distinct groups, Old World coral snakes and New World coral snakes...
. - VespidVespidThe Vespidae are a large , diverse, cosmopolitan family of wasps, including nearly all the known eusocial wasps and many solitary wasps. Each social wasp colony includes a queen and a number of female workers with varying degrees of sterility relative to the queen. In temperate social species,...
wasps bear several harmless mimics including moths, beetles and hoverflies. - Octopuses of the genus Thaumoctopus (the Mimic OctopusMimic OctopusThe Mimic Octopus, Thaumoctopus mimicus, is a species of octopus that has a strong ability to mimic other creatures. It grows up to 60 cm in length. Its normal colouring consists of brown and white stripes or spots....
) are able to intentionally alter their body shape and color so that they resemble dangerous sea snakesSea SnakesSea Snakes were a Canadian indie rock band, formed in 2002 and disbanded in 2005. The band consisted of vocalist and guitarist Jimmy McIntyre, guitarist Kristian Galberg, bassist and saxophonist Jeremy Strachan, keyboardist Shaw-Han Liem and drummer Nathan Lawr.Strachan played in the defunct band...
or lionfishPteroisPterois is a genus of venomous marine fish found mostly in the Indo-Pacific, known collectively as the lionfish. Pterois is characterized by red, white and black stripes, showy pectoral fins and venomous spiky tentacles. Pterois are classified into fifteen different species, but Pterois radiata,...
.
Müllerian
Fritz Müller
Johann Friedrich Theodor Müller , better known as Fritz Müller, and also as Müller-Desterro, was a German biologist and physician who emigrated to southern Brazil, where he lived in and near the German community of Blumenau, Santa Catarina...
put forward the first explanation for this phenomenon: If two species were confused with one another by a common predator, individuals in both would be more likely to survive. This type of mimicry is unique in several respects. Firstly, both the mimic and the model benefit from the interaction, which could thus be classified as mutualism in this respect. The signal receiver is also advantaged by this system, despite being deceived regarding species identity, as it avoids potentially harmful encounters. The usually clear identity of mimic and model are also blurred. In cases where one species is scarce and another abundant, the rare species can be said to be the mimic. When both are present in similar numbers however it is more realistic to speak of each as comimics than of a distinct 'mimic' and 'model' species, as their warning signals tend to converge toward something intermediate between the two. Also, the two species may exist on a continuum from harmless to highly noxious, so Batesian mimicry grades smoothly into Müllerian convergence.
Examples:
- Lepidoptera
- The Monarch Butterfly (Danaus plexippus) is a member of a Müllerian complex with the Viceroy butterflyViceroy butterflyThe Viceroy Butterfly is a North American butterfly with a range from the Northwest Territories along the eastern edges of the Cascade Range and Sierra Nevada mountains, southwards into central Mexico....
(Limenitis archippus) in shared coloration patterns and display behavior. The Viceroy has subspeciesSubspeciesSubspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
with somewhat different coloration, each one very closely matching the local DanausDanaus (genus)Danaus, commonly called Tigers, Milkweeds, Monarchs, and Queens, is a genus of butterflies in the tiger butterfly tribe. They are found worldwide, including North America, South America, Africa, Asia, Indonesia and Australia...
species. E.g., in FloridaFloridaFlorida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, the pairing is of the Viceroy and the Queen ButterflyQueen (butterfly)The Queen Butterfly is a North and South American butterfly in the family Nymphalidae with a wingspan of 2.75–3.25" . It is orange or brown with black wing borders and small white forewing spots on its dorsal wing surface, and reddish ventral wing surface fairly similar to the dorsal surface...
, and in MexicoMexicoThe United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
, the Viceroy resembles the Soldier Butterfly. Therefore, the Viceroy is a single species involved in three different Müllerian pairs. 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, though there is considerable individual variation. While L. archippus is really bad-tasting, Danaus species tend to be toxic rather than just repugnant, due to their different food plants. - Unpalatable EuploeaEuploeaEuploea is a genus of milkweed butterflies. The species are generally dark in coloration, often quite blackish, for which reason they are commonly called crows. As usual for their subfamily, they are poisonous due to feeding on milkweeds and other toxic plants as caterpillars...
species look very similar. See also under Batesian mimicry above. - The genus Morpho is palatable but some species (such as M. amathonteMorpho amathonteMorpho amathonte is a Neotropical butterfly found in Panama, Costa Rica, Venezuela, Colombia and Ecuador.It is considered, by some authors, to be a subspecies of Morpho menelaus.The genus Morpho is palatable but some species Morpho amathonte is a Neotropical butterfly found in Panama, Costa...
) 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 may be a case of Müllerian mimicry, or may be 'pursuit aposematism'. - The "orange complex" of species, including the heliconiines Agraulis vanillae, Dryadula phaetusaDryadula phaetusaDryadula phaetusa, also known as the Banded Orange Heliconian, Banded Orange, or Orange Tiger, is a species of butterfly . The sole representative of its genus, the Banded Orange Heliconian is native from Brazil to central Mexico, and in summer it can be found rarely as far north as central Kansas...
, and Dryas iulia which all taste bad. - Many different tiger moths make ultrasonic clicking calls to warn bats that they are unpalatable. Presumably a bat may learn to avoid any signalling moths, which would make this an example of Müllerian mimicry.
- The Monarch Butterfly (Danaus plexippus) is a member of a Müllerian complex with the Viceroy butterfly
- Various beeBeeBees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
s and numerous vespidVespidThe Vespidae are a large , diverse, cosmopolitan family of wasps, including nearly all the known eusocial wasps and many solitary wasps. Each social wasp colony includes a queen and a number of female workers with varying degrees of sterility relative to the queen. In temperate social species,...
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). Females of most of these species are potentially harmful to predators, fulfilling the second requirement of Müllerian mimicry. However, in essentially all such species, the males are harmless, and can thus be considered automimics of their conspecific females (see below). There are also many genera in these groups where the females are not capable of stinging, and yet still possess aposematic coloration (e.g., the wasp genus CercerisCercerisThe genus Cerceris of the subfamilly Philanthinae is in the family Crabronidae. This is the largest genus in the family, with over 1000 described species and numerous more undescribed. The genus consists of solitary, predatory wasps, most of which prey on beetles...
), so they are considered Batesian mimics.
Emsleyan/Mertensian
Emsleyan or Mertensian mimicry describes unusual cases where deadly prey mimic a less dangerous species. It was first proposed by Emsley as a possible answer for the problem of Coral SnakeCoral snake
The coral snakes are a large group of elapid snakes that can be subdivided into two distinct groups, Old World coral snakes and New World coral snakes...
mimicry in the New World. It was elaborated on by the German biologist Wolfgang Wickler
Wolfgang Wickler
Wolfgang Wickler is a German zoologist, behavioral researcher and publicist. As of 1974, he led the ethological department of the Max Planck Institute for Behavioral Physiology in Seewiesen near Starnberg and he took over as director of the institute in 1975...
in a chapter of Mimicry in Plants and Animals, who named it after the German herpetologist Robert Mertens
Robert Mertens
Robert Mertens was a German herpetologist. The Robert Mertens' day gecko is a species named after him, and he also postulated Mertensian mimicry....
. Sheppard points out that Hecht and Marien put forward a similar hypothesis ten years earlier.
This scenario is a little more difficult to understand, as in other types of mimicry it is usually the most harmful species that is the model. But if a predator dies, it cannot learn
Learning
Learning is acquiring new or modifying existing knowledge, behaviors, skills, values, or preferences and may involve synthesizing different types of information. The ability to learn is possessed by humans, animals and some machines. Progress over time tends to follow learning curves.Human learning...
to recognize a warning signal, e.g. bright colors in a certain pattern. In other words, there is no advantage in being aposematic for an organism that is likely to kill any predator it succeeds in poisoning; such an animal would rather profit from being camouflaged, to avoid attacks altogether. If, however, there is some other species that is harmful but not deadly as well as aposematic, the predator may learn to recognize its particular warning colors and avoid such animals. A deadly species will then profit by mimicking the less dangerous aposematic organism, if this results in less attacks than camouflage would.
The exception here, ignoring any chance of animals learning by watching
Observational learning
Observational learning is a type of learning that occurs as a function of observing, retaining and replicating novel behavior executed by others...
a conspecific die (see Jouventin et al. for a discussion of observational learning and mimicry), is the possibility of not having to learn that it is harmful in the first place: instinct
Instinct
Instinct or innate behavior is the inherent inclination of a living organism toward a particular behavior.The simplest example of an instinctive behavior is a fixed action pattern, in which a very short to medium length sequence of actions, without variation, are carried out in response to a...
ive genetic programming to be wary of certain signals. In this case, other organisms could benefit from this programming, and Batesian or Müllerian mimics of it could potentially evolve. In fact, it has been shown that some species do have an innate recognition of certain aposematic warnings. Hand-reared Turquoise-browed Motmot
Turquoise-browed Motmot
The Turquoise-browed Motmot also called Torogoz by the inhabitants of El Salvador and Guardabarranco in Nicaragua; is a colourful, medium-sized bird of the motmot family, Momotidae. It inhabits Central America from south-east Mexico , to Costa Rica, where it is common and not considered threatened...
s (Eumomota superciliosa), avian predators, instinctively avoid snakes with red and yellow rings. Other colors with the same pattern, and even red and yellow stripes with the same width as rings, were tolerated. However, models with red and yellow rings were feared, with the birds flying away and giving alarm call
Alarm call
In the field of animal communication, an alarm signal is an antipredator adaptation referring to various signals emitted by social animals in response to danger. Many primates and birds have elaborate alarm calls for warning conspecifics of approaching predators. For example, the characteristic...
s in some cases. This provides one alternative explanation to Mertensian mimicry. See Greene and McDiarmid for a review of the subject.
Examples:
- Some Milk SnakeMilk SnakeThe milk snake or milksnake is a species of king snake. There are 25 subspecies among the milk snakes, including the commonly named scarlet kingsnake...
(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 rings. In this system, both the milk snakes and the deadly coral snakes are mimics, whereas the false coral snakes are the model.
Wasmannian
WasmannianErich Wasmann
Erich Wasmann was an Austrian entomologist, specializing in ants and termites, and Jesuit priest. He described the phenomenon known as Wasmannian mimicry. Wasmann was a supporter of evolution, although he did not accept the productivity of natural selection, the evolution of humans from other...
mimicry refers to cases where the mimic resembles a model along with which it lives (inquiline
Inquiline
In zoology, an inquiline is an animal that lives commensally in the nest, burrow, or dwelling place of an animal of another species. For example, some organisms such as insects may live in the homes of gophers and feed on debris, fungi, roots, etc...
) in a nest or colony. Most of the models here are social
Eusociality
Eusociality is a term used for the highest level of social organization in a hierarchical classification....
insects such as ants, termites, bees and wasps.
Mimetic weeds
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...
s which come to share characteristics with a domesticated plant
Crop (agriculture)
A crop is a non-animal species or variety that is grown to be harvested as food, livestock fodder, fuel or for any other economic purpose. Major world crops include maize , wheat, rice, soybeans, hay, potatoes and cotton. While the term "crop" most commonly refers to plants, it can also include...
through artificial selection
Artificial selection
Artificial selection describes intentional breeding for certain traits, or combination of traits. The term was utilized by Charles Darwin in contrast to natural selection, in which the differential reproduction of organisms with certain traits is attributed to improved survival or reproductive...
. It is named after Russian botanist and geneticist
Geneticist
A geneticist is a biologist who studies genetics, the science of genes, heredity, and variation of organisms. A geneticist can be employed as a researcher or lecturer. Some geneticists perform experiments and analyze data to interpret the inheritance of skills. A geneticist is also a Consultant or...
Nikolai Vavilov
Nikolai Vavilov
Nikolai Ivanovich Vavilov was a prominent Russian and Soviet botanist and geneticist best known for having identified the centres of origin of cultivated plants...
. Selection against the weed may occur either by manually killing the weed, or separating its seeds from those of the crop. The latter process, known as winnowing, can be done manually or by a machine.
Vavilovian mimicry presents an illustration of unintentional (or rather 'anti-intentional') selection by man. While some cases of artificial selection go in the direction desired, such as selective breeding
Selective breeding
Selective breeding is the process of breeding plants and animals for particular genetic traits. Typically, strains that are selectively bred are domesticated, and the breeding is sometimes done by a professional breeder. Bred animals are known as breeds, while bred plants are known as varieties,...
, this case presents the opposite characteristics. Weeders do not want to select weeds that look increasingly like the cultivated plant, yet there is no other option. A similar problem in agriculture is pesticide
Pesticide resistance
Pesticide resistance is the adaptation of pest population targeted by a pesticide resulting in decreased susceptibility to that chemical. In other words, pests develop a resistance to a chemical through natural selection: the most resistant organisms are the ones to survive and pass on their...
. Vavilovian mimics may eventually be domesticated themselves, and Vavilov called these weeds-cum-crops secondary crops.
It can be classified as defensive mimicry in that the weed mimics a protected species. This bears strong similarity to Batesian mimicry in that the weed does not share the properties that give the model its protection, and both the model and the dupe (in this case people) are harmed by its presence. There are some key differences, though; in Batesian mimicry
Batesian mimicry
Batesian mimicry is a form of mimicry typified by a situation where a harmless species has evolved to imitate the warning signals of a harmful species directed at a common predator...
the model and signal receiver are enemies (the predator would eat the protected species if could), whereas here the crop and its human growers are in a mutualistic relationship: the crop benefits from being dispersed and protected by people, despite being eaten by them. In fact, the crop's only 'protection' relevant here is its usefulness to humans. Secondly, the weed is not eaten, but simply destroyed. The only motivation for killing the weed is its effect on crop yields. Finally, this type of mimicry does not occur in ecosystems unaltered by humans.
One case is Echinochloa oryzoides
Echinochloa oryzoides
Echinochloa oryzoides is a species of grass known by the common name early barnyard grass. Its origin is not certain but it may be Eurasia. The grass is known in rice-growing areas of the world as a weed of rice paddies.-External links:***...
, a species of grass which is found as a weed in rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
(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.
Protective egg decoys
Unlike the above forms of mimicry, Gilbertian mimicry involves only two species. The potential host/prey drives away its parasite/predator by mimicking it, the reverse of host-parasite aggressive mimicry. It was coined by Pasteur as a term for such rare mimicry systems, and is named after the American ecologist Lawrence E. Gilbert.This form of protective mimicry occurs in the genus Passiflora. The leaves of this plant contain toxins which deter herbivorous animals, however some Heliconius
Heliconius
Heliconius comprise a colorful and widespread brush-footed butterfly genus distributed throughout the tropical and subtropical regions of the New World. These butterflies utilize Passion flower plants as their larval food source and rely on bright wing color patterns to signal their distastefulness...
butterfly larvae have evolved enzymes which break down these toxins, allowing them to specialize on this genus. This has created further selection pressure on the host plants, which have evolved stipules that mimic mature Heliconius eggs near the point of hatching. These butterflies tend to avoid laying eggs near each existing ones, which helps avoid exploitative intraspecific competition
Intraspecific competition
Intraspecific competition is a particular form of competition in which members of the same species vie for the same resource in an ecosystem...
between caterpillars—those that lay on vacant leaves provide their offspring with a greater chance of survival. Additionally, most Heliconius larvae are cannibalistic
Cannibalism (zoology)
In zoology, cannibalism is the act of one individual of a species consuming all or part of another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded for more than 1500 species...
, meaning those leaves with older eggs will hatch first and eat the new arrivals. Thus, it seems such plants have evolved egg dummies due to these grazing herbivore enemies. The decoy eggs are also nectaries though, attracting predators of the caterpillars such as ants and wasps. The extent of their mimetic function is therefore slightly more difficult to assess.
The use of eggs is not essential to this system, only the species composition and protective function. Many other forms of mimicry also involve eggs, such as cuckoo eggs mimicking those of their host (the reverse of this situation), or plants seeds (often those with an elaiosome
Elaiosome
Elaiosomes are fleshy structures that are attached to the seeds of many plant species. The elaiosome is rich in lipids and proteins, and may be variously shaped. Many plants have elaiosomes to attract ants, which take the seed to their nest and feed the elaiosome to their larvae...
) being dispersed by ants, who treat them as they would their own eggs.
Protective mimicry within a species
Browerian mimicry, named after Lincoln P. Brower and Jane Van Zandt Brower, is a form of automimicry; where the model belongs to the same species as the mimic. This is the analogue of Batesian mimicry within a single species, and occurs when there is a palatability spectrum within a population. One example is Monarch Butterflies (Danaus plexippus), which feed on milkweed species of varying toxicity. This species stores toxins from its host plant, which are maintained even in the adult (imagoImago
In biology, the imago is the last stage of development of an insect, after the last ecdysis of an incomplete metamorphosis, or after emergence from the pupa where the metamorphosis is complete...
) form. As the levels of toxin will vary depending on diet during the larval stage, some individuals will be more toxic than others. The less palatable organisms will therefore be mimics of the more dangerous individuals, with their likeness already perfected. This need not be the case however; in sexually dimorphic species one sex may be more of a threat than the other, which could mimic the protected sex. Evidence for this possibility is provided by the behavior of a monkey from Gabon
Gabon
Gabon , officially the Gabonese Republic is a state in west central Africa sharing borders with Equatorial Guinea to the northwest, Cameroon to the north, and with the Republic of the Congo curving around the east and south. The Gulf of Guinea, an arm of the Atlantic Ocean is to the west...
, which regularly ate male moths of the genus Anaphe, but promptly stopped after it tasted a noxious female.
Aggressive
Aggressive mimicry describes predators (or parasites) which share the same characteristics as a harmless species, allowing them to avoid detection by their prey (or hostHost (biology)
In biology, a host is an organism that harbors a parasite, or a mutual or commensal symbiont, typically providing nourishment and shelter. In botany, a host plant is one that supplies food resources and substrate for certain insects or other fauna...
). The mimic may resemble the prey or host itself, or another organism which is either neutral or beneficial to the signal receiver. In this class of mimicry the model may be affected negatively, positively or not at all. Just as parasites can be treated as a form of predator, host-parasite mimicry is treated here as a subclass of aggressive mimicry.
The mimic may have a particular significance for duped prey. One such case is spider
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
s, amongst which aggressive mimicry is quite common in both luring prey and stealthily approaching predators. One case is the Golden Orb Weaver (Nephila clavipes), which spins a conspicuous golden colored web in well-lit areas. Experiments show that bees are able to associate the webs with danger when the yellow pigment is not present, as occurs in less well-lit areas where the web is much harder to see. Other colors were also learned and avoided, but bees seemed least able to effectively associate yellow pigmented webs with danger. Yellow is the color of many nectar bearing flowers, however, so perhaps avoiding yellow is not worth while. Another form of mimicry is based not on color
Color
Color or colour is the visual perceptual property corresponding in humans to the categories called red, green, blue and others. Color derives from the spectrum of light interacting in the eye with the spectral sensitivities of the light receptors...
but pattern. Species such as Argiope argentata
Argiope argentata
Argiope argentata is a member of the Argiope genus of spiders and is also known as the Silver Argiope.-Description:As with most members of the Argiope genus the female of the species tends to be much larger than the male...
employ prominent patterns in the middle of their webs, such as zigzags. These may reflect ultraviolet light, and mimic the pattern seen in many flowers known as nectar guide
Nectar guide
Nectar guides are patterns seen in some species of flowers, guiding pollinators to their rewards. Rewards commonly take the form of nectar, pollen, or both, but various plants produce oil, resins, scents, or waxes...
s. Spiders change their web day to day, which can be explained by bee's ability to remember web patterns. Bees are able to associate a certain pattern with a spatial location, meaning the spider must spin a new pattern regularly or suffer diminishing prey capture.
Another case is where males are lured towards what would seem to be a sexually receptive female; the model in this situation being the same species as the dupe. Beginning in the 1960s, James E. Lloyd's investigation of female fireflies
Firefly
Lampyridae is a family of insects in the beetle order Coleoptera. They are winged beetles, and commonly called fireflies or lightning bugs for their conspicuous crepuscular use of bioluminescence to attract mates or prey. Fireflies produce a "cold light", with no infrared or ultraviolet frequencies...
of the genus Photuris
Photuris (genus)
Photuris is a genus of fireflies wherein are the femme fatale fireflies of North America. This common name refers to the fact that the females of these predatory beetles mimic the light signals of other firefly species' males, to attract, kill, and eat them...
revealed they emit the same light signals that females of the genus Photinus
Photinus (beetle)
The rover fireflies are a genus of fireflies . They are the type genus of tribe Photinini in subfamily Lampyrinae. This genus contains, for example, the common eastern firefly , the state insect of Tennessee.Male Photinus beetles emit a flashing light pattern to signal for females...
use as a mating signal. Further research showed male fireflies from several different genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
are attracted to these "femmes fatales", and are subsequently captured and eaten. Female signals are based on that received from the male, each female having a repertoire of signals matching the delay and duration of the female of the corresponding species. This mimicry may have evolved from non-mating signals that have become modified for predation.
Some carnivorous plant
Carnivorous plant
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants appear adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic...
s may also be able to increase their rate of capture through mimicry.
A case of the latter situation is a species of cleaner fish
Cleaner fish
Cleaner fish are fish that provide a service to other fish species by removing dead skin and ectoparasites. This is an example of mutualism, an ecological interaction that benefits both parties involved. A wide variety of fishes have been observed to display cleaning behaviors including wrasses,...
and its mimic, though in this example the model is greatly disadvantaged by the presence of the mimic. Cleaner fish are the allies of many other species, which allow them to eat their parasites and dead skin. Some allow the cleaner to venture inside their body to hunt these parasites. However, one species of cleaner, the Bluestreak cleaner wrasse
Bluestreak cleaner wrasse
The bluestreak cleaner wrasse is one of several species of cleaner wrasse found on coral reefs in the Indian Ocean and much of the Pacific Ocean, as well as many seas, including the Red Sea and those around Southeast Asia...
(Labroides dimidiatus), is the unknowing model of a mimetic species, the Sabre-toothed blenny (Aspidontus taeniatus). This wrasse
Wrasse
The wrasses are a family, Labridae, of marine fish, many of which are brightly colored. The family is large and diverse, with over 600 species in 82 genera, which are divided into nine subgroups or tribes....
, shown to the left cleaning a grouper
Grouper
Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes.Not all serranids are called groupers; the family also includes the sea basses. The common name grouper is usually given to fish in one of two large genera: Epinephelus...
of the genus Epinephelus
Epinephelus
Epinephelus is a genus of groupers. They are large sea fish. Members of this genus may also be called a Mero.-Species:FishBase lists 99 species:* Areolate grouper, Epinephelus areolatus ....
, resides in coral reef
Coral reef
Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...
s in the Indian and the Pacific Oceans, and is recognized by other fishes who then allow it to clean them. Its imposter, a species of blenny, lives in the Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
and not only looks like it in terms of size and coloration, but even mimics the cleaner's 'dance'. Having fooled its prey into letting its guard down, it then bites it, tearing off a piece of its fin before fleeing the scene. Fish grazed
Grazing
Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...
upon in this fashion soon learn to distinguish mimic from model, but because the similarity is close between the two they become much more cautious of the model as well, such that both are affected. Due to victim's ability to discriminate between foe and helper, the blennies have evolved close similarity, right down to the regional level.
Another interesting example that does not involve any luring is the Zone-tailed Hawk
Zone-tailed Hawk
The Zone-tailed Hawk is a medium-sized hawk of warm, dry parts of the Americas. It feeds on small vertebrates of all kinds , including birds up to the size of quail....
, which resembles the Turkey Vulture
Turkey Vulture
The Turkey Vulture is a bird found throughout most of the Americas. It is also known in some North American regions as the Turkey Buzzard , and in some areas of the Caribbean as the John Crow or Carrion Crow...
. It flies amongst the vultures, suddenly breaking from the formation and ambushing its prey. Here the hawk's presence is of no evident significance to the vultures, affecting them neither negatively or positively.
Parasites
Parasites can also be aggressive mimics, though the situation is somewhat different from those outlined above.Some of the predators described have a feature that draws prey, and parasites can also mimic their host's natural prey, but are eaten themselves, a pathway into their host. Leucochloridium
Leucochloridium
Leucochloridium is genus of parasitic worms.-Species:Species in the genus Leucochloridium include:* Leucochloridium caryocatactis * Leucochloridium fuscostriatum Robinson, 1948...
, a genus of flatworm
Flatworm
The flatworms, known in scientific literature as Platyhelminthes or Plathelminthes are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrate animals...
, matures in the digestive system of songbird
Songbird
A songbird is a bird belonging to the suborder Passeri of the perching birds . Another name that is sometimes seen as scientific or vernacular name is Oscines, from Latin oscen, "a songbird"...
s, their eggs then passing out of the bird via the feces
Feces
Feces, faeces, or fæces is a waste product from an animal's digestive tract expelled through the anus or cloaca during defecation.-Etymology:...
. They are then taken up by Succinea
Succinea
Succinea, common name amber snails, is a genus of small, air-breathing, land snails, terrestrial pulmonate gastropod molluscs in the family Succineidae.They usually live in damp habitats such as marshes.-Species:...
, a terrestrial snail. The eggs develop in this intermediate host
Intermediate host
A secondary host or intermediate host is a host that harbors the parasite only for a short transition period, during which some developmental stage is completed. For trypanosomes, the cause of sleeping sickness, humans are the primary host, while the tsetse fly is the secondary host...
, and then must find of a suitable bird to mature in. As the host birds do not eat snails, so the sporocyst has another strategy to reach its host's intestine. They are brightly colored and move in a pulsating fashion. A sporocyst-sac pulsates in the snail's eye stalks, coming to resemble an irresistible meal for a songbird. In this way, it can bridge the gap between hosts, allowing it to complete its life cycle. A nematode (Myrmeconema neotropicum
Myrmeconema neotropicum
Myrmeconema neotropicum is a tetradonematid nematode parasite.At present, the only known host species is Cephalotes atratus, a South American ant with a black abdomen...
) changes the colour of the abdomen of workers of the canopy ant Cephalotes atratus to make it appear like the ripe fruits of Hyeronima alchorneoides. It also changes the behaviour of the ant so that the gaster
Gaster
The gaster is the bulbous posterior portion of the metasoma found in Apocrita Hymenoptera . This begins with abdominal segment III on most ants, but some make a postpetiole out of segment III, in which case the gaster begins with abdominal segment IV....
(rear part) is held raised. This presumably increases the chances of the ant being eaten by birds. The droppings of birds are collected by other ants and fed to their brood, thereby helping to spread the nematode.
In an unusual case, planidium
Planidium
A planidium is a specialized type of first-instar insect larva, seen in groups that are parasitoids; they are generally flattened, highly sclerotized, have legs, are quite mobile, and sometimes have eyes...
larvae of some beetles of the genus Meloe
Meloe
The blister beetle genus Meloe is a large, widespread group commonly referred to as oil beetles. They are known as "oil beetles" because they release oily droplets of hemolymph from their joints when disturbed; this contains cantharidin, a poisonous chemical causing blistering of the skin and...
will form a group and produce a pheromone
Pheromone
A pheromone is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting outside the body of the secreting individual to impact the behavior of the receiving individual...
that mimics the sex attractant of its host bee
Apidae
The Apidae are a large family of bees, comprising the common honey bees, stingless bees , carpenter bees, orchid bees, cuckoo bees, bumblebees, and various other less well-known groups...
species; when the male bee arrives and attempts to mate with the mass of larvae, they climb onto his abdomen, and from there transfer to a female bee, and from there to the bee nest to parasitize the bee larvae.
Host-parasite mimicry is a two species system where a parasite mimics its own host. Cuckoo
Cuckoo
The cuckoos are a family, Cuculidae, of near passerine birds. The order Cuculiformes, in addition to the cuckoos, also includes the turacos . Some zoologists and taxonomists have also included the unique Hoatzin in the Cuculiformes, but its taxonomy remains in dispute...
s are a canonical example of brood parasitism, a form of kleptoparasitism
Kleptoparasitism
Kleptoparasitism or cleptoparasitism is a form of feeding in which one animal takes prey or other food from another that has caught, collected, or otherwise prepared the food, including stored food...
where the mother has its offspring raised by another unwitting organism, cutting down the biological mother's parental investment
Parental investment
In evolutionary biology, parental investment is any parental expenditure that benefits one offspring at a cost to parents' ability to invest in other components of fitness...
in the process. The ability to lay eggs which mimic the host eggs is the key adaptation
Adaptation
An adaptation in biology is a trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation....
. The adaptation to different hosts is inherited through the female line in so-called gentes. Cases of intraspecific brood parasitism, where a female lays in conspecific's nest, as illustrated by the Goldeneye
Goldeneye (duck)
Goldeneye are small tree-hole nesting northern hemisphere seaducks belonging to the genus Bucephala. Their plumage is black and white, and they eat fish, crustaceans and other marine life....
duck (Bucephala clangula), do not represent a case of mimicry.
Reproductive
Reproductive mimicry occurs when the actions of the dupe directly aid in the mimic's reproduction. This is common in plants, which may have deceptive flowers that do not provide the reward they would seem to. Other forms of mimicry have a reproductive component, such as Vavilovian mimicry involving seeds, and brood parasitism, which also involves aggressive mimicry.Mimicry of flowers
Bakerian mimicry, named after Herbert G. Baker, is a form of automimicry where female flowerFlower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s mimic male flowers of their own species, cheating pollinators out of a reward. This reproductive mimicry may not be readily apparent as members of the same species may still exhibit some degree of sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
. It is common in many species of Caricaceae
Caricaceae
Caricaceae are a family of flowering plants in the order Brassicales, native to tropical regions of Central and South America and Africa. They are short-lived evergreen pachycaul shrubs or small trees growing to 5-10 m tall...
.
Like Bakerian mimicry, Dodsonian mimicry is a form of reproductive floral mimicry, but the model belongs to a different species than the mimic. The name refers to Calaway H. Dodson
Calaway H. Dodson
Calaway Homer Dodson is an American botanist, orchidologist, and taxonomist.- Biography :Dodson specialized in orchidology very early in his career...
. By providing similar sensory signals as the model flower, it can lure its pollinators. Like Bakerian mimics, no nectar is provided. Epidendrum ibaguense
Epidendrum ibaguense
Epidendrum ibaguense is a species of epiphytic orchid of the genus Epidendrum which occurs in Trinidad, French Guyana, Venezuela, Colombia and Northern Brazil.There is a good article on this species in the Português Wikipedia...
of the family Orchidaceae
Orchidaceae
The Orchidaceae, commonly referred to as the orchid family, is a morphologically diverse and widespread family of monocots in the order Asparagales. Along with the Asteraceae, it is one of the two largest families of flowering plants, with between 21,950 and 26,049 currently accepted species,...
resembles flowers of Lantana camara
Lantana camara
Lantana camara, also known as Spanish Flag or West Indian Lantana, is a species of flowering plant in the verbena family, Verbenaceae, that is native to the American tropics. It has been introduced into other parts of the world as an ornamental plant and is considered an invasive species in many...
and Asclepias curassavica
Asclepias curassavica
Asclepias curassavica, commonly called Mexican Butterfly Weed, Blood-flower, Scarlet Milkweed or, Tropical Milkweed, is a species of flowering plant in the dogbane family, Apocynaceae. It is native to the American tropics....
, and is pollinated by Monarch Butterflies and perhaps hummingbird
Hummingbird
Hummingbirds are birds that comprise the family Trochilidae. They are among the smallest of birds, most species measuring in the 7.5–13 cm range. Indeed, the smallest extant bird species is a hummingbird, the 5-cm Bee Hummingbird. They can hover in mid-air by rapidly flapping their wings...
s. Similar cases are seen in some other species of the same family. The mimetic species may still have pollinators of its own though, for example a lamellicorn beetle which usually pollinates correspondingly colored Cistus
Cistus
Cistus is a genus of flowering plants in the rockrose family Cistaceae, containing about 20 species . They are perennial shrubs found on dry or rocky soils throughout the Mediterranean region, from Morocco and Portugal through to the Middle East, and also on the Canary Islands...
flowers is also known to aid in pollination of Ophrys
Ophrys
The genus Ophrys is a large group of orchids from the alliance Orchis in the subtribe Orchidinae. There are many natural hybrids. The type species is Ophrys insectifera L.1753...
species that are normally pollinated by bees.
Pseudocopulation
Pseudocopulation occurs when a flower mimics a female of a certain insect species, the males of which try to copulate with it. This is much like the aggressive mimicry in fireflies described above, but with a much more benign outcome for the pollinator. This form of mimicry has been called Pouyannian mimicry, after Pouyanne, who first described the phenomenon. It is most common in orchids which mimic females of the order HymenopteraHymenoptera
Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. There are over 130,000 recognized species, with many more remaining to be described. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and...
(generally bees and wasps), and may account for around 60% of pollinations. Depending on the morphology of the flower, a pollen sac called a pollinia is attached to the head or abdomen of the male. This is then transferred to the stigma of the next flower the male tries to inseminate, resulting in pollination. Visual mimicry is the most obvious sign of this deception for humans, but the visual aspect may be minor or non-existent. It is the senses of touch and olfaction
Olfaction
Olfaction is the sense of smell. This sense is mediated by specialized sensory cells of the nasal cavity of vertebrates, and, by analogy, sensory cells of the antennae of invertebrates...
that are most important.
Inter-sexual mimicry
Inter-sexual mimicry occurs when individuals of one sex in a species mimic members of the opposite sex. An example is the three male forms of the marine isopod, Paracerceis sculptaParacerceis sculpta
Paracerceis sculpta is a species of marine isopod between and in length. The species lives mainly in the intertidal zone, and is native to the Northeast Pacific from Southern California to Mexico, but has since been introduced to many other countries. Adults are herbivorous and consume algae but...
. Alpha males are the largest and guard a harem
Harem
Harem refers to the sphere of women in what is usually a polygynous household and their enclosed quarters which are forbidden to men...
of females. Beta males mimic females and manage to enter the harem of females without being detected by the alpha males allowing them to mate. Gamma males are the smallest males and mimic juveniles. This also allows them to mate with the females without the alpha males detecting them. Some male Australian Giant Cuttlefish
Australian Giant Cuttlefish
Sepia apama, also known as the Australian Giant Cuttlefish, is the world's largest cuttlefish species, growing to 50 cm in mantle length and over 10.5 kg in weight. Using cells known as chromatophores, the cuttlefish can put on spectacular displays, changing colour in an instant.S...
also mimic females, allowing them to mate undetected by other males.
Automimicry
Automimicry or intraspecific mimicry occurs within a single species, one case being where one part of an organism's body resembles another 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 eyespotEyespot (mimicry)
An eyespot is an eye-like marking. They are found on butterflies, reptiles, birds and fish. In members of the Felidae family , the white circular markings on the backs of the ears are termed ocelli, and they are functionally similar to eyespots in other animals.Eyespots may be a form of...
s on their hind ends to resemble the head. The term is also used when the mimic imitates other morphs within the same species. When males mimic females or vice versa this may be referred to as sexual mimicry
Sexual mimicry
Sexual mimicry is where one sex takes the characteristics of the other within a species. Examples of sexual mimicry in animals are the spotted hyena, bonobo chimp, spider monkey, lemur, european mole and some insects...
.
Examples:
- 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 owlPygmy owlPygmy Owls are members of the genus Glaucidium. They belong to the typical owl family Strigidae, one of the two generally accepted living families of owls....
s bear "false eyes" on the back of their head to fool predators into believing the owl is alert to their presence. - The yellow throated males of the Common Side-blotched LizardCommon side-blotched lizardThe common side-blotched lizard is a species of side-blotched lizard common on the Pacific coast of North America, from Washington to western Texas and NW Mexico...
use a 'sneaking' strategy in matingMatingIn biology, mating is the pairing of opposite-sex or hermaphroditic organisms for copulation. In social animals, it also includes the raising of their offspring. Copulation is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization...
. They look and behave like unreceptive females. This strategyEvolutionary game theoryEvolutionary game theory is the application of Game Theory to evolving populations of lifeforms in biology. EGT is useful in this context by defining a framework of contests, strategies and analytics into which Darwinian competition can be modelled. It originated in 1973 with John Maynard Smith...
is effective against 'usurper' males with orange throats, but ineffective against blue throated 'guarder' males, which will chase them away. - Female hyenaHyenaHyenas or Hyaenas are the animals of the family Hyaenidae of suborder feliforms of the Carnivora. It is the fourth smallest biological family in the Carnivora , and one of the smallest in the mammalia...
s have pseudo-penisPseudo-penisA pseudo-penis is a term used of any structure found on an animal that while superficially appearing to be a penis, is derived from a different developmental path.-Mammals:...
es which make them look like males.
Other
Some forms of mimicry do not fit easily within the classification given above.Owl butterflies (genus Caligo) bear eye-spots on the underside of their wings; if turned upside-down, their undersides resemble the face of an owl
Owl
Owls are a group of birds that belong to the order Strigiformes, constituting 200 bird of prey species. Most are solitary and nocturnal, with some exceptions . Owls hunt mostly small mammals, insects, and other birds, although a few species specialize in hunting fish...
(such as the Short-eared Owl
Short-eared Owl
The Short-eared Owl is a species of typical owl . In Scotland this species of owl is often referred to as a cataface, grass owl or short-horned hootlet. Owls belonging to genus Asio are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or may...
or the Tropical Screech Owl) for which in turn the butterfly predators – small lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
s and birds – would be fooled. Thus it has been supposed that the eye-spots are a form of Batesian mimicry. However, the pose in which the butterfly resembles an owl's head is not normally adopted in life. Research suggests that eye-spots are not a form of mimicry and do not deter predators because they look like eyes. Rather the conspicuous contrast in the patterns on the wings deter predators.
Another case is floral mimicry induced by the discomycete fungus Monilinia vaccinii-corymbosi. In this unusual case, a fungal plant pathogen infects leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
of blueberries, causing them to secrete sugary substances including glucose and fructose, in effect mimicking the nectar of flowers. To the naked eye the leaves do not look like flowers, yet strangely they still attract pollinating insects like bees. As it turns out, the sweet secretions are not the only cues—the leaves also reflect ultraviolet
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...
, which is normally absorbed by the plant's leaves. Ultraviolet light is also employed by the host's flowers as a signal to insects, which have visual systems quite capable of picking up this low wavelength (300–400 nm) radiation. The fungus is then transferred to the ovaries of the flower where it produces mummified, inedible berries, which overwinter before infecting new plants. This case is unusual in that the fungus benefits from the deception, but it is the leaves which act as mimics, being harmed in the process. It bears similarity to host-parasite mimicry, but the host does not receive the signal. It also has a little in common with automimicry, but the plant does not benefit from the mimicry, and the action of the pathogen is required to produce it.
Evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
as a positive adaptation; that is, the mimic gains fitness gradually via convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
which results in resemblance to another species. The lepidopterist and writer Vladimir Nabokov
Vladimir Nabokov
Vladimir Vladimirovich Nabokov was a multilingual Russian novelist and short story writer. Nabokov wrote his first nine novels in Russian, then rose to international prominence as a master English prose stylist...
argued that although natural selection might stabilize a "mimic" form, it would not be necessary to create it. It may be that much of insect mimicry, including the Viceroy/Monarch mimicry, results from similar self-organizing processes, and thus the tendency for convergence by chance would be high.
The most widely accepted model used to explain the evolution of mimicry in butterflies is the two-step hypothesis. In this model the first step involves mutation in modifier genes that regulate a complex cluster of linked genes associated with large changes in morphology. The second step consists of selections on genes with smaller phenotypic effects and this leading to increasing closeness of resemblance. This model is supported by empirical evidence that suggests that there are only a few single point mutations that cause large phenotypic effects while there are numerous others that produce smaller effects. Some regulatory elements are now known to be involved in a supergene
Supergene
A supergene is a group of neighbouring genes on a chromosome which are inherited together because of close genetic linkage and are functionally related in an evolutionary sense, although they are rarely co-regulated genetically....
that is involved in the development of butterfly color patterns. Computational simulations of population genetics have also supported this idea.
See also
- Animal coloration
- BiomimicryBiomimicryBiomimicry or biomimetics is the examination of nature, its models, systems, processes, and elements to emulate or take inspiration from in order to solve human problems. The term biomimicry and biomimetics come from the Greek words bios, meaning life, and mimesis, meaning to imitate...
- CamouflageCamouflageCamouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...
- Community ecology
- Evolutionary ecologyEvolutionary ecologyEvolutionary ecology lies at the intersection of ecology and evolutionary biology. It approaches the study of ecology in a way that explicitly considers the evolutionary histories of species and the interactions between them. Conversely, it can be seen as an approach to the study of evolution that...
- Code-breaking
- Molecular mimicryMolecular mimicryMolecular mimicry is defined as the theoretical possibility that sequence similarities between foreign and self-peptides are sufficient to result in the cross-activation of autoreactive T or B cells by pathogen-derived peptides...
- PreadaptationPreadaptationIn evolutionary biology, preadaptation describes a situation where a species evolves to use a preexisting structure or trait inherited from an ancestor for a potentially unrelated function...
- SemioticsSemioticsSemiotics, also called semiotic studies or semiology, is the study of signs and sign processes , indication, designation, likeness, analogy, metaphor, symbolism, signification, and communication...
- Thanatosis ('playing dead')
- Underwater camouflage and mimicryUnderwater camouflage and mimicryUnderwater camouflage and mimicry is a technique of crypsis—avoidance of observation—that allows an otherwise visible aquatic organism to remain indiscernible from the surrounding environment, or pretend to be something else by mimicking another organism or object...
Similar terms
- Mimetic is an adjective used to describe cases of mimicry, but is also used in mathematics (see mimeticMimeticIn mathematics, mimesis is the quality of a numerical method which imitates some properties of the continuum problem. The goal of numerical analysis is to approximate the continuum, so instead of solving a partial differential equation one aims to solve a discrete version of the continuum problem...
). This should not be confused with memeticsMemeticsMemetics is a theory of mental content based on an analogy with Darwinian evolution, originating from Richard Dawkins' 1976 book The Selfish Gene. It purports to be an approach to evolutionary models of cultural information transfer. A meme, analogous to a gene, is essentially a "unit of...
, the scientific study of memeMemeA meme is "an idea, behaviour or style that spreads from person to person within a culture."A meme acts as a unit for carrying cultural ideas, symbols or practices, which can be transmitted from one mind to another through writing, speech, gestures, rituals or other imitable phenomena...
s. - MimesisMimesisMimesis , from μιμεῖσθαι , "to imitate," from μῖμος , "imitator, actor") is a critical and philosophical term that carries a wide range of meanings, which include imitation, representation, mimicry, imitatio, receptivity, nonsensuous similarity, the act of resembling, the act of expression, and the...
also refers to imitationImitationImitation is an advanced behavior whereby an individual observes and replicates another's. The word can be applied in many contexts, ranging from animal training to international politics.-Anthropology and social sciences:...
, especially relating to the artArtArt is the product or process of deliberately arranging items in a way that influences and affects one or more of the senses, emotions, and intellect....
s.
Further reading
- Cott, H.B.Hugh B. CottHugh B. Cott , born Hugh Bamford Cott, was a British zoologist, an authority on both natural and military camouflage, and a scientific illustrator and photographer. Many of his field studies took place in Africa, where he was especially interested in the Nile crocodile.-Background:Cott was born in...
(1940) Adaptive Coloration in Animals. Methuen and Co, Ltd., London ISBN 0-416-30050-2 - Wickler, W.Wolfgang WicklerWolfgang Wickler is a German zoologist, behavioral researcher and publicist. As of 1974, he led the ethological department of the Max Planck Institute for Behavioral Physiology in Seewiesen near Starnberg and he took over as director of the institute in 1975...
(1968) Mimicry in Plants and Animals (Translated from the German) McGraw-Hill, New York. ISBN 0-07-070100-8 - Edmunds, M. 1974. Defence in Animals: a survey of anti-predator defences. Harlow, Essex and NY: Longman. ISBN 0-582-44132-3
- Owen, D. (1980) Camouflage and Mimicry. Oxford University Press ISBN 0-19-217683-8
- Brower, L. (ed., 1988). Mimicry and the evolutionary process. Chicago: The University of Chicago Press. ISBN 0-226-07608-3 (a supplement of volume 131 of the journal American NaturalistAmerican NaturalistThe American Naturalist is a monthly peer-reviewed scientific journal that was established in 1867. It is published by the University of Chicago Press on behalf of the American Society of Naturalists. The journal covers research in ecology, evolutionary biology, population, and integrative biology....
dedicated to E. B. Ford.) - Ruxton, G. D.Graeme RuxtonGraeme Ruxton is Professor of theoretical ecology at the University of Glasgow, Scotland, United Kingdom. His studies focus on the evolutionary pressures on aggregation by animals, and predator-prey aspects of sensory ecology...
; Speed, M. P.; Sherratt, T. N. (2004). Avoiding Attack: the evolutionary ecology of crypsis, warning signals and mimicry. Oxford: Oxford University Press. ISBN 0-19-852860-4 - An introductory book for a younger audience: Hoff, M. K. (2003) Mimicry and Camouflage. Creative Education. Mankato, Minn. Great Britain. ISBN 1-58341-237-9
External links
- Warning Colour and Mimicry Lecture outline from University College LondonUniversity College LondonUniversity College London is a public research university located in London, United Kingdom and the oldest and largest constituent college of the federal University of London...
- Camouflage and Mimicry in Fossils
- Chemical Mimicry in Pollination
- Learn about Butterflies Simple account.