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 copulate with a

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism ...

. Some flowers mimic a potential female mate visually, but the key stimuli are often chemical and tactile. This form of mimicry in plants is called Pouyannian mimicry.

Orchid Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

s commonly achieve reproduction in this manner, secreting chemicals from glands (osmophores) in the

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined ...

petal Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usuall ...

s, or labellum, that are indistinguishable from the insect's natural

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 like hormones outside the body of the secreting individual, to affect the behavio ...

s. The pollinator then has a

pollinium A pollinium (plural pollinia) is a coherent mass of pollen grains in a plant that are the product of only one anther, but are transferred, during pollination, as a single unit. This is regularly seen in plants such as orchids and many species of m ...

attached to its body, which it transfers to the stigma of another flower when it attempts another 'copulation'. Pollinators are often

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, and

wasp A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. Th ...

s of the order Hymenoptera, and

flies Flies are insects of the Order (biology), order Diptera, the name being derived from the Ancient Greek, Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwing ...

. The cost to the pollinating insects might be seen as negligible, but study of ''

Cryptostylis ''Cryptostylis'', commonly known as tongue orchids, is a genus of flowering plants from the orchid family. Tongue orchids are terrestrial herbs with one to a few stalked leaves at the base of the flowering stem, or leafless. One to a few dull co ...

'' (an Australian orchid) pollinators shows that they may waste large amounts of sperm by ejaculating onto the flower. Thus there could be antagonistic

coevolution 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 ...

such that pollinators become better at identifying their own species correctly and orchids become better mimics. "Pseudocopulation" is also used to describe close physical contact between mating animals whose eggs are externally fertilized.

Frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" '' Triadobatrachus'' is ...

s provide one such case, with the male releasing sperm as the female discharges her eggs, a process called

amplexus Amplexus (Latin "embrace") is a type of mating behavior exhibited by some externally fertilizing species (chiefly amphibians and horseshoe crabs) in which a male grasps a female with his front legs as part of the mating process, and at the sam ...

. In some species of starfish, a male and female may come together and form a pair. The male climbs on top, placing his arms between those of the female. When she releases eggs into the water, he is induced to release his sperm. "Pseudocopulation" is also used to mean behaviours of birds that appear to be copulating but may merely involve mounting and could involve pairs of the same sex.

References

{{animal sexual behavior Mimicry Animal sexuality Sexual acts Pollination

See also

References