Pseudocopulation in the context of "Parthenogenesis"

In biology, coevolution occurs when two or more species reciprocally affect each other's evolution 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.

Charles Darwin mentioned evolutionary interactions between flowering plants and insects in On the Origin of Species (1859). He used use the similar word coadaptation and 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.

Aggressive mimicry is a form of mimicry in which predators, parasites, or parasitoids share similar signals, using a harmless model, allowing them to avoid being correctly identified by their prey or host. Zoologists have repeatedly compared this strategy to a wolf in sheep's clothing. In its broadest sense, aggressive mimicry could include various types of exploitation, as when an orchid exploits a male insect by mimicking a sexually receptive female (see pseudocopulation), but will here be restricted to forms of exploitation involving feeding. For example, indigenous Australians who dress up as and imitate kangaroos when hunting would not be considered aggressive mimics, nor would a human angler, though they are undoubtedly practising self-decoration camouflage. Treated separately is molecular mimicry, which shares some similarity; for instance a virus may mimic the molecular properties of its host, allowing it access to its cells. An alternative term, Peckhamian mimicry, has been suggested (after George and Elizabeth Peckham), but it is seldom used.

Aggressive mimicry is opposite in principle to defensive mimicry, where the mimic generally benefits from being treated as harmful. The mimic may resemble its own prey, or some other organism which is beneficial or at least not harmful to the prey. The model, i.e. the organism being 'imitated', may experience increased or reduced fitness, or may not be affected at all by the relationship. On the other hand, the signal receiver inevitably suffers from being tricked, as is the case in most mimicry complexes.

Pouyannian mimicry is a form of mimicry in plants that deceives an insect into attempting to copulate with a flower. The flower mimics a potential female mate of a male insect, which then serves the plant as a pollinator. The mechanism is named after the French lawyer and amateur botanist Maurice-Alexandre Pouyanne. The resemblance that he noted is visual, but the key stimuli that deceive the pollinator are often chemical and tactile.

In orchids, the resemblance is to a species of bee; Pouyanne observed the bee Dasyscolia ciliata pollinating the orchid Ophrys speculum. The flower uses morphology, coloration, and scent to deceive the pollinator. The chemicals secreted from the flower's osmophore glands are indistinguishable from the insect's pheromones. The pollinator is not rewarded with nectar, and may waste significant amounts of sperm while trying to mate with the flower.

Dasyscolia ciliata is a species of scoliid wasp found throughout the Mediterranean. It is the only species in the genus Dasyscolia. It is the only known pollinator of the European Ophrys speculum. The male wasp is tricked into pollinating the Ophrys orchid via pseudocopulation. The orchid's Pouyannian mimicry has the flower effectively mimicking the female wasp in appearance and scent.

In evolutionary biology, mimicry in plants is where a plant evolves to resemble another organism physically or chemically. Mimicry in plants has been studied far less than mimicry in animals. It may provide protection against herbivory, or may deceptively encourage mutualists, like pollinators, to provide a service without offering a reward in return.

Types of plant mimicry include Bakerian mimicry, where female flowers imitate males of the same species; Dodsonian mimicry, where a plant mimics a rewarding flower, luring pollinators by mimicking another species of flower, or fruit where feeders of the other species are attracted to a fake fruit to distribute seeds; Gilbertian, where a plant has structures like butterfly eggs, dissuading egg-laying; Vavilovian, where a weed is unintentionally selected to resemble a crop plant; Pouyannian, in which a flower imitates a female mate, deceiving a male pollinating insect into pseudocopulation; Batesian, where a harmless species deters predators by mimicking the characteristics of a harmful species; and leaf mimicry, where a plant is camouflaged by resembling a nearby plant to evade the attention of herbivores.