A wide variety of animals participate in communal child rearing, from pack hunters that form family social groups, including orcas, lions, wolves and chimpanzees, to other groups of animals including elephants in both Asia and Africa. Some animals that collectively raise their young, such as lions, include a group of females who rear the children of a the single male in the pack. In these cases, new males who join the pack may kill the young of the previously dominant male in order to ensure that the females of the group will have to produce new offspring with him.
Other animals that raise children in groups include those with matriarchal societies. Elephants fall under this category, with female elephants leading family groups that include grandmothers, mothers, aunts, sisters and their young. Asian elephants have been observed to share parenting duties among their family groups, with elephants caring for the children of other group members when that member is unavailable or otherwise indisposed. In these groups, families stay close together, with female elephants staying with their family groups for their whole lives. Male elephants will leave their family group once they reach maturity to prevent inbreeding. Elephant family groups are notoriously close knit, and their members have been observed mourning dead relatives.