Copulation

Copulation is sexual intercourse between animals, typically involving transfer of sperm from one individual to another. Its forms vary across species, anatomy, and reproductive strategies.

Sperm transfer: The movement of sperm from a male reproductive system to a female reproductive system or other recipient. Copulation commonly transfers sperm, though the route and structures differ among animals.
Penis: An organ used by many animals to deliver sperm or sperm-containing fluid during reproduction. In many species, this organ transfers sperm during copulation.
Sexual reproduction: Reproduction involving the combination of genetic material from two gametes. Copulation is one route by which animals bring gametes together.
Sexual conflict: Evolutionary disagreement between the reproductive interests of individuals of different sexes. Mating can benefit one partner while imposing costs on the other.
Internal fertilization: Fertilization in which sperm and egg unite inside an organism's body. Copulation often enables sperm to reach eggs within the reproductive tract.
Cloaca: A shared opening for digestive, urinary, and reproductive tracts in many vertebrates. Birds and some other animals copulate through brief cloacal contact.
Mating system: A population's pattern of sexual pairing, including how many partners individuals have and for how long. Mating systems shape who copulates with whom and how often.
Sperm competition: Competition between sperm from different males to fertilize the same set of eggs. Repeated mating can place sperm from multiple partners in competition.
External fertilization: Fertilization in which eggs and sperm unite outside the parents' bodies, usually in water. Many animals reproduce without copulation by releasing gametes into the environment.
Traumatic insemination: A reproductive strategy in which a male pierces a mate's body wall to deposit sperm. Bed bugs provide a striking example of copulation without conventional genital insertion.

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MatingBroader topic: Copulation is one specific form of mating, common in internal fertilization.