![Dasyscolia ciliata](https://upload.wikimedia.org/wikipedia/commons/1/17/Dasyscolia_ciliata.jpg)
In biology, coevolution occurs when two or more
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
reciprocally affect each other's
evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
through the process of natural selection. The term sometimes is used for two traits in the same species affecting each other's evolution, as well as
gene-culture coevolution
Dual inheritance theory (DIT), also known as gene–culture coevolution or biocultural evolution, was developed in the 1960s through early 1980s to explain how human behavior is a product of two different and interacting evolutionary processes: gen ...
.
Charles Darwin
Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended fr ...
mentioned evolutionary interactions between
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s and
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s in ''
On the Origin of Species
''On the Origin of Species'' (or, more completely, ''On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life''),The book's full original title was ''On the Origin of Species by Me ...
'' (1859). Although he did not use the word coevolution, he suggested how plants and insects could evolve through reciprocal evolutionary changes. Naturalists in the late 1800s studied other examples of how interactions among species could result in reciprocal evolutionary change. Beginning in the 1940s, plant pathologists developed breeding programs that were examples of human-induced coevolution. Development of new crop plant varieties that were resistant to some diseases favored rapid evolution in pathogen populations to overcome those plant defenses. That, in turn, required the development of yet new resistant crop plant varieties, producing an ongoing cycle of reciprocal evolution in crop plants and diseases that continues to this day.
Coevolution as a major topic for study in nature expanded rapidly after the middle 1960s, when Daniel H. Janzen showed coevolution between acacias and ants (see below) and
Paul R. Ehrlich
Paul Ralph Ehrlich (born May 29, 1932) is an American biologist known for his warnings about the consequences of population growth and limited resources. He is the Bing Professor Emeritus of Population Studies of the Department of Biology of St ...
and
Peter H. Raven
Peter Hamilton Raven (born June 13, 1936) is an American botanist and environmentalist, notable as the longtime director, now President Emeritus, of the Missouri Botanical Garden.
Early life
On June 13, 1936, Raven was born in Shanghai, Chi ...
suggested how
coevolution between plants and butterflies may have contributed to the diversification of species in both groups. The theoretical underpinnings of coevolution are now well-developed (e.g., the geographic mosaic theory of coevolution), and demonstrate that coevolution can play an important role in driving major evolutionary transitions such as the evolution of sexual reproduction or shifts in ploidy.
More recently, it has also been demonstrated that coevolution can influence the structure and function of ecological communities, the evolution of groups of mutualists such as plants and their pollinators, and the dynamics of infectious disease.
Each party in a coevolutionary relationship exerts
selective pressures on the other, thereby affecting each other's evolution. Coevolution includes many forms of
mutualism,
host-parasite, and
predator-prey
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...
relationships between species, as well as
competition within or
between species. In many cases, the selective pressures drive an
evolutionary arms race
In evolutionary biology, an evolutionary arms race is an ongoing struggle between competing sets of co-evolving genes, phenotypic and behavioral traits that develop escalating adaptations and counter-adaptations against each other, resembling an a ...
between the species involved. Pairwise or specific coevolution, between exactly two species, is not the only possibility; in multi-species coevolution, which is sometimes called guild or diffuse coevolution, several to many species may evolve a trait or a group of traits in reciprocity with a set of traits in another species, as has happened between the flowering plants and
pollinating
Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by wind. Pollinating agents can be animals such as insects, birds, a ...
insects such as
bee
Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyly, monophyletic lineage within the ...
s,
flies
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...
, and
beetle
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...
s. There are a suite of specific hypotheses on the mechanisms by which groups of species coevolve with each other.
Coevolution is primarily a biological concept, but researchers have applied it by analogy to fields such as
computer science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical discipli ...
,
sociology
Sociology is a social science that focuses on society, human social behavior, patterns of Interpersonal ties, social relationships, social interaction, and aspects of culture associated with everyday life. It uses various methods of Empirical ...
, and
astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
.
Mutualism
Coevolution is the
evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
of two or more
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
which reciprocally affect each other, sometimes creating a
mutualistic relationship between the species. Such relationships can be of many different types.
Flowering plants
Flowers appeared and diversified relatively suddenly in the fossil record, creating what
Charles Darwin
Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended fr ...
described as the "abominable mystery" of how they had evolved so quickly; he considered whether coevolution could be the explanation.
He first mentioned coevolution as a possibility in ''
On the Origin of Species
''On the Origin of Species'' (or, more completely, ''On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life''),The book's full original title was ''On the Origin of Species by Me ...
'', and developed the concept further in ''
Fertilisation of Orchids
''Fertilisation of Orchids'' is a book by English naturalist Charles Darwin published on 15 May 1862 under the full explanatory title ''On the Various Contrivances by Which British and Foreign Orchids Are Fertilised by Insects, and On the Good ...
'' (1862).
Insects and insect-pollinated flowers
![Apis mellifera - Melilotus albus - Keila](https://upload.wikimedia.org/wikipedia/commons/f/f4/Apis_mellifera_-_Melilotus_albus_-_Keila.jpg)
Modern
insect-pollinated (entomophilous) flowers are conspicuously coadapted with insects to ensure pollination and in return to reward the
pollinator
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.
Insects are the maj ...
s with nectar and pollen. The two groups have coevolved for over 100 million years, creating a complex network of interactions. Either they evolved together, or at some later stages they came together, likely with pre-adaptations, and became mutually adapted.
Several highly successful
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
groups—especially the
Hymenoptera
Hymenoptera is a large order (biology), order of insects, comprising the sawfly, sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are Par ...
(wasps, bees and ants) and
Lepidoptera
Lepidoptera ( ) is an order (biology), order of insects that includes butterfly, butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 Family (biology), families and 46 Taxonomic r ...
(butterflies and moths) as well as many types of
Diptera
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...
(flies) and
Coleoptera
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...
(beetles)—evolved in conjunction with
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s during the
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...
(145 to 66 million years ago). The earliest bees, important pollinators today, appeared in the early Cretaceous.
A group of wasps
sister
A sister is a woman or a girl who shares one or more parents with another individual; a female sibling. The male counterpart is a brother. Although the term typically refers to a familial relationship, it is sometimes used endearingly to refer to ...
to the bees evolved at the same time as flowering plants, as did the Lepidoptera.
[ Further, all the major ]clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...
s of bees first appeared between the middle and late Cretaceous, simultaneously with the adaptive radiation of the eudicots
The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons.
Traditionally they were called tricolpates or non-magnoliid dico ...
(three quarters of all angiosperms), and at the time when the angiosperms became the world's dominant plants on land.
At least three aspects of flowers appear to have coevolved between flowering plants and insects, because they involve communication between these organisms. Firstly, flowers communicate with their pollinators by scent; insects use this scent to determine how far away a flower is, to approach it, and to identify where to land and finally to feed. Secondly, flowers attract insects with patterns of stripes leading to the rewards of nectar and pollen, and colours such as blue and ultraviolet, to which their eyes are sensitive; in contrast, bird-pollinated flowers tend to be red or orange. Thirdly, flowers such as some orchids mimic females of particular insects, deceiving males into pseudocopulation
Pseudocopulation describes behaviors similar to copulation that serve a reproductive function for one or both participants but do not involve actual sexual union between the individuals. It is most generally applied to a pollinator attempting to co ...
.
The yucca
''Yucca'' is a genus of perennial shrubs and trees in the family Asparagaceae, subfamily Agavoideae. Its 40–50 species are notable for their rosettes of evergreen, tough, sword-shaped leaves and large terminal panicles of white or whitish flo ...
, ''Yucca whipplei'', is pollinated exclusively by ''Tegeticula maculata'', a yucca moth
The Prodoxidae are a family of moths, generally small in size and nondescript in appearance. They include species of moderate pest status, such as the currant shoot borer, and others of considerable ecological and evolutionary interest, such as ...
that depends on the yucca for survival. The moth eats the seeds of the plant, while gathering pollen. The pollen has evolved to become very sticky, and remains on the mouth parts when the moth moves to the next flower. The yucca provides a place for the moth to lay its eggs, deep within the flower away from potential predators.
Birds and bird-pollinated flowers
Hummingbird
Hummingbirds are birds native to the Americas and comprise the biological family Trochilidae. With about 361 species and 113 genera, they occur from Alaska to Tierra del Fuego, but the vast majority of the species are found in the tropics aro ...
s and ornithophilous (bird-pollinated) flowers have evolved a mutualistic relationship. The flowers have nectar
Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...
suited to the birds' diet, their color suits the birds' vision and their shape fits that of the birds' bills. The blooming times of the flowers have also been found to coincide with hummingbirds' breeding seasons. The floral characteristics of ornithophilous plants vary greatly among each other compared to closely related insect-pollinated species. These flowers also tend to be more ornate, complex, and showy than their insect pollinated counterparts. It is generally agreed that plants formed coevolutionary relationships with insects first, and ornithophilous species diverged at a later time. There is not much scientific support for instances of the reverse of this divergence: from ornithophily to insect pollination. The diversity in floral phenotype in ornithophilous species, and the relative consistency observed in bee-pollinated species can be attributed to the direction of the shift in pollinator preference.
Flowers have converged to take advantage of similar birds. Flowers compete for pollinators, and adaptations reduce unfavourable effects of this competition. The fact that birds can fly during inclement weather makes them more efficient pollinators where bees and other insects would be inactive. Ornithophily may have arisen for this reason in isolated environments with poor insect colonization or areas with plants which flower in the winter. Bird-pollinated flowers usually have higher volumes of nectar and higher sugar production than those pollinated by insects.
This meets the birds' high energy requirements, the most important determinants of flower choice. In ''Mimulus
Mimulus is a plant genus in the family Phrymaceae, which was traditionally placed in family Scrophulariaceae. The genus now contains only seven species, two native to eastern North America and the other five native to Asia, Australia, Africa, ...
'', an increase in red pigment in petals and flower nectar volume noticeably reduces the proportion of pollination by bees as opposed to hummingbirds; while greater flower surface area increases bee pollination. Therefore, red pigments in the flowers of ''Mimulus cardinalis'' may function primarily to discourage bee visitation. In ''Penstemon
''Penstemon'' , the beardtongues, is a large genus of roughly 250 species of flowering plants native mostly to the Nearctic, but with a few species also found in the North American portion of the Neotropics. It is the largest genus of flowering ...
'', flower traits that discourage bee pollination may be more influential on the flowers' evolutionary change than 'pro-bird' adaptations, but adaptation 'towards' birds and 'away' from bees can happen simultaneously. However, some flowers such as ''Heliconia angusta
''Heliconia angusta'' Vell. ( syn.: ''Heliconia agustifolia'' Hook., ''Heliconia bicolor'' Benth., ''Heliconia brasiliensis'' Hook.), of family Heliconiaceae is an erect herb typically growing 0.70 m tall, native to Brazil (South America).
Gene ...
'' appear not to be as specifically ornithophilous as had been supposed: the species is occasionally (151 visits in 120 hours of observation) visited by ''Trigona
''Trigona'' is one of the largest genera of stingless bees, comprising about 32 species, exclusively occurring in the New World, and formerly including many more subgenera than the present assemblage; many of these former subgenera have been el ...
'' stingless bees. These bees are largely pollen robbers in this case, but may also serve as pollinators.
Following their respective breeding seasons, several species of hummingbirds occur at the same locations in North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
, and several hummingbird flowers bloom simultaneously in these habitats. These flowers have converged to a common morphology
Morphology, from the Greek and meaning "study of shape", may refer to:
Disciplines
* Morphology (archaeology), study of the shapes or forms of artifacts
* Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...
and color because these are effective at attracting the birds. Different lengths and curvatures of the corolla tubes can affect the efficiency of extraction in hummingbird species in relation to differences in bill morphology. Tubular flowers force a bird to orient its bill in a particular way when probing the flower, especially when the bill and corolla are both curved. This allows the plant to place pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...
on a certain part of the bird's body, permitting a variety of morphological co-adaptation In biology, co-adaptation is the process by which two or more species, genes or phenotypic traits undergo adaptation as a pair or group. This occurs when two or more interacting characteristics undergo natural selection together in response to the ...
s.
Ornithophilous flowers need to be conspicuous to birds. Birds have their greatest spectral sensitivity and finest hue discrimination at the red end of the visual spectrum
The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called ''visible light'' or simply light. A typical human eye will respond to wavele ...
, so red is particularly conspicuous to them. Hummingbirds may also be able to see ultraviolet "colors". The prevalence of ultraviolet patterns and nectar guides in nectar-poor entomophilous (insect-pollinated) flowers warns the bird to avoid these flowers. Each of the two subfamilies of hummingbirds, the Phaethornithinae (hermits) and the Trochilinae
Trochilinae is one of the six subfamilies that make up the hummingbird family Trochilidae.
The subfamily is divided into three tribes: Lampornithini (mountain gems) containing 18 species, Mellisugini (bees) containing 37 species and Trochilini (e ...
, has evolved in conjunction with a particular set of flowers. Most Phaethornithinae species are associated with large monocotyledon
Monocotyledons (), commonly referred to as monocots, (Lilianae ''sensu'' Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of ...
ous herbs, while the Trochilinae prefer dicotyledon
The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, t ...
ous plant species.
Fig reproduction and fig wasps
The genus ''Ficus
''Ficus'' ( or ) is a genus of about 850 species of woody trees, shrubs, vines, epiphytes and hemiepiphytes in the family Moraceae. Collectively known as fig trees or figs, they are native throughout the tropics with a few species extending in ...
'' is composed of 800 species of vines, shrubs, and trees, including the cultivated fig, defined by their syconium
Syconium (plural ''syconia'') is the type of inflorescence borne by figs (genus ''Ficus''), formed by an enlarged, fleshy, hollow receptacle with multiple ovaries on the inside surface. In essence, it is really a fleshy stem with a number of flow ...
s, the fruit-like vessels that either hold female flowers or pollen on the inside. Each fig species has its own fig wasp
Fig wasps are wasps of the superfamily Chalcidoidea which spend their larval stage inside figs. Most are pollinators but others simply feed off the plant. The non-pollinators belong to several groups within the superfamily Chalcidoidea, while th ...
which (in most cases) pollinates the fig, so a tight mutual dependence has evolved and persisted throughout the genus.
Acacia ants and acacias
The acacia ant (''Pseudomyrmex ferruginea'') is an obligate plant ant that protects at least five species of "Acacia" (''Vachellia
''Vachellia'' is a genus of flowering plants in the legume family, Fabaceae, commonly known as thorn trees or acacias. It belongs to the subfamily Mimosoideae. Its species were considered members of genus ''Acacia'' until 2009. ''Vachellia'' can ...
'') from preying insects and from other plants competing for sunlight, and the tree provides nourishment and shelter for the ant and its larvae. Such mutualism is not automatic: other ant species exploit trees without reciprocating, following different evolutionary strategies. These cheater ants impose important host costs via damage to tree reproductive organs, though their net effect on host fitness is not necessarily negative and, thus, becomes difficult to forecast.
Hosts and parasites
Parasites and sexually reproducing hosts
Host–parasite coevolution
Host–parasite coevolution is a special case of coevolution, where a host and a parasite continually adapt to each other. This can create an evolutionary arms race between them. A more benign possibility is of an evolutionary trade-off between ...
is the coevolution of a host
A host is a person responsible for guests at an event or for providing hospitality during it.
Host may also refer to:
Places
* Host, Pennsylvania, a village in Berks County
People
*Jim Host (born 1937), American businessman
* Michel Host ...
and a parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
. A general characteristic of many viruses, as obligate parasite
An obligate parasite or holoparasite is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host. If an obligate parasite cannot obtain a host it will fail to reproduce. This is opposed to a facultative parasite, ...
s, is that they coevolved alongside their respective hosts. Correlated mutations between the two species enter them into an evolution arms race. Whichever organism, host or parasite, that cannot keep up with the other will be eliminated from their habitat, as the species with the higher average population fitness survives. This race is known as the Red Queen hypothesis
The Red Queen hypothesis is a hypothesis in evolutionary biology proposed in 1973, that species must constantly adapt, evolve, and proliferate in order to survive while pitted against ever-evolving opposing species. The hypothesis was intended t ...
. The Red Queen hypothesis predicts that sexual reproduction allows a host to stay just ahead of its parasite, similar to the Red Queen's race
The Red Queen's race is an incident that appears in Lewis Carroll's ''Through the Looking-Glass'' and involves both the Red Queen, a representation of a Queen in chess, and Alice constantly running but remaining in the same spot.
"Well, in our ...
in ''Through the Looking-Glass
''Through the Looking-Glass, and What Alice Found There'' (also known as ''Alice Through the Looking-Glass'' or simply ''Through the Looking-Glass'') is a novel published on 27 December 1871 (though indicated as 1872) by Lewis Carroll and the ...
'': "it takes all the running ''you'' can do, to keep in the same place". The host reproduces sexually, producing some offspring with immunity over its parasite, which then evolves in response.
The parasite–host relationship probably drove the prevalence of sexual reproduction over the more efficient asexual reproduction. It seems that when a parasite infects a host, sexual reproduction affords a better chance of developing resistance (through variation in the next generation), giving sexual reproduction variability for fitness not seen in the asexual reproduction, which produces another generation of the organism susceptible to infection by the same parasite. Coevolution between host and parasite may accordingly be responsible for much of the genetic diversity seen in normal populations, including blood-plasma polymorphism, protein polymorphism, and histocompatibility systems.
Brood parasites
Brood parasitism
Brood parasites are animals that rely on others to raise their young. The strategy appears among birds, insects and fish. The brood parasite manipulates a host, either of the same or of another species, to raise its young as if it were its own ...
demonstrates close coevolution of host and parasite, for example in some cuckoo
Cuckoos are birds in the Cuculidae family, the sole taxon in the order Cuculiformes . The cuckoo family includes the common or European cuckoo, roadrunners, koels, malkohas, couas, coucals and anis. The coucals and anis are sometimes separ ...
s. These birds do not make their own nests, but lay their eggs in nests of other species, ejecting or killing the eggs and young of the host and thus having a strong negative impact on the host's reproductive fitness. Their eggs are camouflaged as eggs of their hosts, implying that hosts can distinguish their own eggs from those of intruders and are in an evolutionary arms race with the cuckoo between camouflage and recognition. Cuckoos are counter-adapted to host defences with features such as thickened eggshells, shorter incubation (so their young hatch first), and flat backs adapted to lift eggs out of the nest.
Antagonistic coevolution
Antagonistic coevolution is seen in the harvester ant
Harvester ant, also known as harvesting ant, is a common name for any of the species or genera of ants that collect seeds (called seed predation), or mushrooms as in the case of ''Euprenolepis procera'', which are stored in the nest in communal ...
species ''Pogonomyrmex barbatus
''Pogonomyrmex barbatus'' is a species of harvester ant from the genus ''Pogonomyrmex''. Its common names include red ant and red harvester ant. These large (5– to 7-mm) ants prefer arid chaparral habitats and are native to the Southwestern Uni ...
'' and '' Pogonomyrmex rugosus'', in a relationship both parasitic and mutualistic. The queens are unable to produce worker ants by mating with their own species. Only by crossbreeding can they produce workers. The winged females act as parasites for the males of the other species as their sperm will only produce sterile hybrids. But because the colonies are fully dependent on these hybrids to survive, it is also mutualistic. While there is no genetic exchange between the species, they are unable to evolve in a direction where they become too genetically different as this would make crossbreeding impossible.
Predators and prey
Predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
s and prey interact and coevolve: the predator to catch the prey more effectively, the prey to escape. The coevolution of the two mutually imposes selective pressure
Any cause that reduces or increases reproductive success in a portion of a population potentially exerts evolutionary pressure, selective pressure or selection pressure, driving natural selection. It is a quantitative description of the amount of ...
s. These often lead to an evolutionary arms race
In evolutionary biology, an evolutionary arms race is an ongoing struggle between competing sets of co-evolving genes, phenotypic and behavioral traits that develop escalating adaptations and counter-adaptations against each other, resembling an a ...
between prey and predator, resulting in anti-predator adaptation
Anti-predator adaptations are mechanisms developed through evolution that assist prey organisms in their constant struggle against predators. Throughout the animal kingdom, adaptations have evolved for every stage of this struggle, namely by avo ...
s.
The same applies to herbivore
A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...
s, animals that eat plants, and the plants that they eat. Paul R. Ehrlich
Paul Ralph Ehrlich (born May 29, 1932) is an American biologist known for his warnings about the consequences of population growth and limited resources. He is the Bing Professor Emeritus of Population Studies of the Department of Biology of St ...
and Peter H. Raven
Peter Hamilton Raven (born June 13, 1936) is an American botanist and environmentalist, notable as the longtime director, now President Emeritus, of the Missouri Botanical Garden.
Early life
On June 13, 1936, Raven was born in Shanghai, Chi ...
in 1964 proposed the theory of escape and radiate coevolution
Escape and radiate coevolution is a hypothesis proposing that a coevolutionary 'arms-race' between primary producers and their consumers contributes to the diversification of species by accelerating speciation rates. The hypothesized process inv ...
to describe the evolutionary diversification of plants and butterflies. In the Rocky Mountains
The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...
, red squirrel
The red squirrel (''Sciurus vulgaris'') is a species of tree squirrel in the genus ''Sciurus'' common throughout Europe and Asia. The red squirrel is an arboreal, primarily herbivorous rodent.
In Great Britain, Ireland, and in Italy numbers ...
s and crossbill
The crossbill is a genus, ''Loxia'', of birds in the finch family (Fringillidae), with six species. These birds are characterised by the mandibles with crossed tips, which gives the group its English name. Adult males tend to be red or orange in ...
s (seed-eating birds) compete for seeds of the lodgepole pine
''Pinus contorta'', with the common names lodgepole pine and shore pine, and also known as twisted pine, and contorta pine, is a common tree in western North America. It is common near the ocean shore and in dry montane forests to the subalpine, ...
. The squirrels get at pine seeds by gnawing through the cone scales, whereas the crossbills get at the seeds by extracting them with their unusual crossed mandibles. In areas where there are squirrels, the lodgepole's cones are heavier, and have fewer seeds and thinner scales, making it more difficult for squirrels to get at the seeds. Conversely, where there are crossbills but no squirrels, the cones are lighter in construction, but have thicker scales, making it more difficult for crossbills to get at the seeds. The lodgepole's cones are in an evolutionary arms race with the two kinds of herbivore.[ and the two following pages of the web article.]
Competition
Both intraspecific competition
Intraspecific competition is an interaction in population ecology, whereby members of the same species compete for limited resources. This leads to a reduction in fitness for both individuals, but the more fit individual survives and is able to r ...
, with features such as sexual conflict
Sexual conflict or sexual antagonism occurs when the two sexes have conflicting optimal fitness strategies concerning reproduction, particularly over the mode and frequency of mating, potentially leading to an evolutionary arms race between male ...
and sexual selection
Sexual selection is a mode of natural selection in which members of one biological sex mate choice, choose mates of the other sex to mating, mate with (intersexual selection), and compete with members of the same sex for access to members of t ...
, and interspecific competition
Interspecific competition, in ecology, is a form of competition in which individuals of ''different'' species compete for the same resources in an ecosystem (e.g. food or living space). This can be contrasted with mutualism, a type of symbiosis. ...
, such as between predators, may be able to drive coevolution.
Intraspecific competition can result in sexual antagonistic coevolution, an evolutionary relationship analogous to an arms race
An arms race occurs when two or more groups compete in military superiority. It consists of a competition between two or more states to have superior armed forces; a competition concerning production of weapons, the growth of a military, and t ...
, where the evolutionary fitness of the sexes is counteracted to achieve maximum reproductive success. For example, some insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s reproduce using traumatic insemination
Traumatic insemination, also known as hypodermic insemination, is the mating practice in some species of invertebrates in which the male pierces the female's abdomen with his aedeagus and injects his sperm through the wound into her abdominal c ...
, which is disadvantageous to the female's health. During mating, males try to maximise their fitness by inseminating as many females as possible, but the more times a female's abdomen
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...
is punctured, the less likely she is to survive, reducing her fitness.
Multispecies
The types of coevolution listed so far have been described as if they operated pairwise (also called specific coevolution), in which traits of one species have evolved in direct response to traits of a second species, and vice versa. This is not always the case. Another evolutionary mode arises where evolution is reciprocal, but is among a group of species rather than exactly two. This is variously called guild or diffuse coevolution. For instance, a trait in several species of flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
, such as offering its nectar
Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...
at the end of a long tube, can coevolve with a trait in one or several species of pollinating insects, such as a long proboscis. More generally, flowering plants are pollinated by insects from different families including bee
Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyly, monophyletic lineage within the ...
s, flies
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...
, and beetle
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...
s, all of which form a broad guild
A guild ( ) is an association of artisans and merchants who oversee the practice of their craft/trade in a particular area. The earliest types of guild formed as organizations of tradesmen belonging to a professional association. They sometimes ...
of pollinator
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.
Insects are the maj ...
s which respond to the nectar or pollen produced by flowers.[Juenger, Thomas, and Joy Bergelson. "Pairwise versus diffuse natural selection and the multiple herbivores of scarlet gilia, Ipomopsis aggregata." Evolution (1998): 1583–1592.]
Geographic mosaic theory
The geographic mosaic theory of coevolution was developed by John N. Thompson as a way of linking the ecological and evolutionary processes that shape interactions among species across ecosystems. It is based on three observations that are taken as assumptions: (1) species are usually groups of populations that are somewhat genetically distinct from each other, (2) interacting species often co-occur in only parts of their geographic ranges, and (3) interactions among species differ ecologically among environments.
From these assumptions, geographic mosaic theory suggests that natural selection on interactions among species is driven by three sources of variation:
1. ''Geographic selection mosaics'' occur in interactions among species, because genes are expressed in different ways in different environments and because different genes are favored in different environments. For example, natural selection on an interaction between a parasite population and a host population may differ between very dry environments and very wet environments. Alternatively, an interaction between two or more species may be antagonistic in some environments but mutualistic (beneficial to both or all species) in other environments.
2. ''Coevolutionary hotspots and coldspots'' occur because natural selection on interactions among species is reciprocal in some environments but not in others. For example, a symbiont population may decrease the survival or reproduction of its hosts in one environment, but it may have no effect on host survival or reproduction in another environment. When detrimental, natural selection will favor evolutionary responses in the host population, resulting in a coevolutionary hotspot of ongoing reciprocal evolutionary changes in the parasite and host populations. When the symbiont has no effect on the survival and reproduction of the host, natural selection on the symbiont population will not favor an evolutionary response by the host population (i.e, a coevolutionary coldspot).
3. Finally, there is constant ''remixing of the traits'' on which natural selection acts both locally and regionally. At any moment in time, a local population will have a unique combination of genes on which natural selection acts. These genetic differences among populations occur because each local population has a unique history of new mutations, genomic alterations (e.g., whole genome duplications), gene flow among populations from individuals arriving from other populations or going to other populations, random loss or fixation of genes at times when populations are small (random genetic drift), hybridization with other species, and other genetic and ecological processes that affect the raw genetic material on which natural selection acts. More formally, then, the geographic mosaic of coevolution can be viewed as a genotype by genotype by environment interaction (GxGxE) that results in the relentless evolution of interacting species.
Geographic mosaic theory has been explored through a wide range of mathematical models, studies of interacting species in nature, and laboratory experiments using microbial species and viruses.
Outside biology
Coevolution is primarily a biological concept, but has been applied to other fields by analogy.
In algorithms
Coevolutionary algorithms are used for generating artificial life
Artificial life (often abbreviated ALife or A-Life) is a field of study wherein researchers examine systems related to natural life, its processes, and its evolution, through the use of simulations with computer models, robotics, and biochemistry ...
as well as for optimization, game learning and machine learning
Machine learning (ML) is a field of inquiry devoted to understanding and building methods that 'learn', that is, methods that leverage data to improve performance on some set of tasks. It is seen as a part of artificial intelligence.
Machine ...
. Daniel Hillis
William Daniel "Danny" Hillis (born September 25, 1956) is an American inventor, entrepreneur, and computer scientist, who pioneered parallel computers and their use in artificial intelligence. He founded Thinking Machines Corporation, a parall ...
added "co-evolving parasites" to prevent an optimization procedure from becoming stuck at local maxima. Karl Sims Karl Sims (born 1962) is a computer graphics artist and researcher, who is best known for using particle systems and artificial life in computer animation.
Biography
Sims received a B.S. from MIT in 1984, and a M.S. from the MIT Media Lab in 1987. ...
coevolved virtual creatures.
In architecture
The concept of coevolution was introduced in architecture by the Danish architect-urbanist Henrik Valeur
Henrik Bjørn Valeur (; born 13 October 1966) is a Danish architect-urbanist, founder and creative director of UiD (Denmark) and UiD Shanghai Co., Ltd (China), curator of ''CO-EVOLUTION: Danish/Chinese Collaboration on Sustainable Urban Development ...
as an antithesis to "star-architecture". As the curator of the Danish Pavilion at the 2006 Venice Biennale of Architecture, he created an exhibition-project on coevolution in urban development in China; it won the Golden Lion for Best National Pavilion.
At the School of Architecture, Planning and Landscape, Newcastle University
Newcastle University (legally the University of Newcastle upon Tyne) is a UK public university, public research university based in Newcastle upon Tyne, North East England. It has overseas campuses in Singapore and Malaysia. The university is ...
, a coevolutionary approach to architecture has been defined as a design practice that engages students, volunteers and members of the local community in practical, experimental work aimed at "establishing dynamic processes of learning between users and designers."
In cosmology and astronomy
In his book ''The Self-organizing Universe'', Erich Jantsch
Erich Jantsch (8 January 1929 12 December 1980) was an Austrian-born American astrophysicist, engineer, educator, author,Emilio Ambasz al. "Erich Jantsch (1929-1980)," in: ''The Universitas Project: Solutions for a Post-technological Society,' ...
attributed the entire evolution of the cosmos
The cosmos (, ) is another name for the Universe. Using the word ''cosmos'' implies viewing the universe as a complex and orderly system or entity.
The cosmos, and understandings of the reasons for its existence and significance, are studied in ...
to coevolution.
In astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
, an emerging theory proposes that black hole
A black hole is a region of spacetime where gravitation, gravity is so strong that nothing, including light or other Electromagnetic radiation, electromagnetic waves, has enough energy to escape it. The theory of general relativity predicts t ...
s and galaxies
A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. ...
develop in an interdependent way analogous to biological coevolution.
In management and organization studies
Since year 2000, a growing number of management and organization studies discuss coevolution and coevolutionary processes. Even so, Abatecola el al. (2020) reveals a prevailing scarcity in explaining what processes substantially characterize coevolution in these fields, meaning that specific analyses about where this perspective on socio-economic change is, and where it could move toward in the future, are still missing.
In sociology
In ''Development Betrayed: The End of Progress and A Coevolutionary Revisioning of the Future'' (1994) Richard Norgaard
Richard B. Norgaard (born August 18, 1943) is a professor emeritus of ecological economics in the Energy and Resources Group at the University of California, Berkeley, the first chair and a continuing member of the independent science board of ...
proposes a coevolutionary cosmology to explain how social and environmental systems influence and reshape each other. In ''Coevolutionary Economics: The Economy, Society and the Environment'' (1994) John Gowdy suggests that: "The economy, society, and the environment are linked together in a coevolutionary relationship".
In technology
Computer software
Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work.
At the lowest programming level, executable code consists ...
and hardware can be considered as two separate components but tied intrinsically by coevolution. Similarly, operating system
An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs.
Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...
s and computer applications
Application may refer to:
Mathematics and computing
* Application software, computer software designed to help the user to perform specific tasks
** Application layer, an abstraction layer that specifies protocols and interface methods used in a c ...
, web browsers, and web applications.
All of these systems depend upon each other and advance step by step through a kind of evolutionary process. Changes in hardware, an operating system or web browser may introduce new features that are then incorporated into the corresponding applications running alongside. The idea is closely related to the concept of "joint optimization" in sociotechnical systems analysis and design, where a system is understood to consist of both a "technical system" encompassing the tools and hardware used for production and maintenance, and a "social system" of relationships and procedures through which the technology is tied into the goals of the system and all the other human and organizational relationships within and outside the system. Such systems work best when the technical and social systems are deliberately developed together.
See also
*Bak–Sneppen model
*Coextinction
*Ecological fitting
*Escape and radiate coevolution
*Genomics of domestication
Notes
References
External links
Coevolution
video of lecture by Stephen C. Stearns (Open Yale Courses)
{{Evolutionary psychology
Ecological processes
Environmental terminology
Evolution of the biosphere
Evolutionary biology
Habitat