Pouyannian mimicry

The form of mimicry in plants that deceives an insect into pseudocopulation is called Pouyannian mimicry after the French lawyer and amateur botanist Maurice-Alexandre Pouyanne. Mimicry typically involves three species, namely a mimic, a model, and a dupe, as seen for example in Batesian mimicry. In the case of Pouyannian mimicry, the model and the dupe are the female and male of the same species, so the mimicry is bipolar, involving only two species, an insect and a flower. , compared to Batesian mimicry. Pouyannian mimicry is bipolar, with only 2 species involved, as the dupe and the model are of the same species, such as a pollinating bee. == History ==

In 1916, Pouyanne, with Henry Correvon, described his observations in Algeria: == In orchids ==

Several orchids (Orchidaceae) make use of floral mimicry. Using sex-based deception, these species imitate female mating signals of certain pollinator species. This results in attempted copulation by males of the pollinator species, facilitating pollen transfer. Bee orchids (Ophrys apifera) and fly orchids (Ophrys insectifera), specifically, utilize flower morphology, coloration, and scent to deceive their respective pollinators. These orchids have evolved traits matching the preferences of specific pollinator niches, leading to adaptive speciation. The mimicry involves secreting chemicals from glands (osmophores) in the sepals, petals, or labellum, that are indistinguishable from the insect's natural pheromones. The flower attaches a pollinium to the pollinator's body; the insect transfers the pollinium to the stigma of another flower when it makes its next copulation attempt. Pollinators are often bees, wasps, or flies. The cost to the pollinating insects might be seen as negligible, but pollinators of the Australian orchid Cryptostylis can waste significant amounts of sperm by ejaculating onto the flower. Thus there could be antagonistic coevolution such that pollinators become better at identifying their own species correctly, while orchids become better mimics. File:Ophrys apifera - panoramio (52).jpg|Mimic: flower of Bee Orchid, Ophrys apifera mimics a female bee to attract male bees as pollinators. File:GL.109 Eucera longicornis f.jpg|Model: Female longhorn bee, Eucera longicornis One mechanism in pollination is to use incentives or rewards. These are beneficial offerings to a pollinator, enticing it to engage with the reward and thus transfer pollen. Flowering plants that do not produce such rewards can instead attract pollinators through mimicry — a form of convergent evolution. Although bee and fly orchids are visual mimics of their pollinators, visual traits are not the only (nor the most important) ones mimicked to increase attraction. Although mimetic plants typically receive fewer interactions with pollinators than truly-rewarding plants do, the evolution of sexual deception appears to be linked to benefits associated with mating behavior. Sex-based mimicry results in pollinator fidelity, the continued revisiting of flowers of the same species by a pollinator, as a result of sexual deception. In support of this, sex-based deception in an Australian orchid results in a higher proportion of pollen reaching stigmas than food-based deception. In another study, deception of male pollinators results in a long-distance dispersal of pollen. == References ==