Fission–fusion societies

In ethology, a fission–fusion society is one in which the size and composition of the social group change as time passes and animals move throughout the environment; animals merge into a group (fusion)—e.g. sleeping in one place—or split (fission)—e.g. foraging in small groups during the day. For species that live in fission–fusion societies, group composition is a dynamic property.

This social organization is found in several primates, elephants, cetaceans, ungulates, social carnivores, some birds and some fish.

This form of social organization occurs in several species of primates (e.g. chimpanzees and bonobos, hamadryas baboons, geladas, orangutans,spider monkeys, and humans), African elephants, gregarious carnivorans like the coyote, spotted hyena,African lion, and cetaceans such as bottlenose dolphins,ungulates such as deer, plains zebras,giraffes,birds such as the great tit and fish such as guppies.

These societies change frequently in their size and composition, making up a permanent social group called the "parent group". Permanent social networks consist of all individual members of a faunal community and often varies to track changes in their environment and based on individual animal dynamics.

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