Allopreening

Social grooming is a behaviour in which social animals, including humans, clean or maintain one another's body or appearance. A related term, allogrooming, indicates social grooming between members of the same species. Grooming is a major social activity, and a means by which animals who live in close proximity may bond and reinforce social structures, family links, or build relationships. Social grooming is also used as a means of conflict resolution and reconciliation in some species. Mutual grooming typically describes the act of grooming between two individuals, often as a part of social grooming, pair bonding, or a precoital activity.

There are a variety of proposed mechanisms by which social grooming behavior has been hypothesized to increase fitness. These evolutionary advantages may come in the form of health benefits including reduced disease transmission and reduced stress levels, maintaining social structure, and direct improvement of fitness as a measure of survival.

Social grooming behavior has been shown to elicit an array of health benefits in a variety of species.  For example, group member connection has the potential to mitigate the potentially harmful effects of stressors. In macaques, social grooming has been proven to reduce heart rate. Social affiliation during a mild stressor was shown to correlate with lower levels of mammary tumor development and longer lifespan in rats, while lack of this affiliation was demonstrated to be a major risk factor. Grooming has also been shown to play an integral role in reducing tick load in wild baboons (Papio cynocephalus). These ectoparasitic ticks carry the potential to act as vectors for the spreading of disease and infection by common tick-borne parasites such as haemoprotozoan. Baboons with lower tick loads show decreased occurrence of such infections and display signs of greater health status, evidenced by higher (packed red cell volume) levels.

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