Mating



In biology, mating is the pairing of opposite-sex or hermaphroditic internal fertilization animals for copulation and, in social animals, also to raise their offspring. Mating methods include random mating, disassortative mating, assortative mating, or a mating pool.

In some birds, for example, it includes nest-building and feeding offspring. The human practice of making domesticated animals mate and of artificially inseminating them is part of animal husbandry.

Copulation is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization. The two individuals may be of opposite sexes or hermaphroditic, as is the case with, for example, snails.

In some terrestrial arthropods, including insects representing basal (primitive) phylogenetic clades, the male deposits spermatozoa on the substrate, sometimes stored within a special structure, and courtship involves inducing the female to take up the sperm package into her genital opening; there is no actual copulation. In groups such as dragonflies and many spiders, males extrude sperm into secondary copulatory structures removed from their genital opening, which are then used to inseminate the female (in dragonflies, it is a set of modified sternites on the second abdominal segment; in spiders, it is the male pedipalps). In advanced groups of insects, the male uses its aedeagus, a structure formed from the terminal segments of the abdomen, to deposit sperm directly (though sometimes in a capsule called a "spermatophore") into the female's reproductive tract.

Many other animals reproduce sexually with external fertilization, including many basal vertebrates. Many vertebrates (such as reptiles, some fish, and most birds) reproduce with internal fertilization through cloacal copulation (see also hemipenis), while mammals copulate vaginally.

In humans, unlike most animals, copulation may or may not be related to reproduction. In most cases people copulate for pleasure; this behaviour is also seen in some animal species, for example chimpanzees and especially bonobos are known to copulate when the female is not fertile, presumably for pleasure, which in turn strengthens social bonds. See also sexual intercourse and human sexual behavior.

Like in animals, mating in other eukaryotes, such as plants and fungi, denotes sexual conjugation. However, in vascular plants this is mostly achieved without physical contact between mating individuals (see pollination), and in some cases, e.g., in fungi no distinguishable male or female organs exist (see isogamy); however, mating types in some fungal species are somewhat analogous to sexual dimorphism in animals, and determine whether or not two individual isolates can mate.