Whether animals have families depends on the animal. Brown bears are generally solitary: the only social bonds they form are between mothers and their young. Tigers usually live alone, except for a mother with her cubs, and a female tiger gives birth every 3 to 4 years, depending on how long her earlier cubs depended on her. Young orangutans may stay with their mothers to nurse for up to seven years, the longest childhood of the great apes. At the other end of the range, a honeybee colony has one reproductive female, the queen, and her offspring, while the workers that care for the young are the queen's sterile daughters, and naked mole-rats are eusocial: a colony has a queen, a few breeding males and non-breeding workers who care for the young and protect the colony.

Birds offer one way to ask why animals help. Florida scrub-jays are one of the few animal groups where scientists have found a clear benefit to the breeding parents from having helpers, and young jays often spend their first several years as helpers in their family group, typically staying in the territory where they were born for at least a year. Helper scrub-jays defend the territory and bring food to the young, but they do not sit on the eggs. Among cooperatively breeding birds, pairs with helpers fledge about one and a half times more young than pairs without helpers, and the helpers are typically related to the breeding pair. A review of cooperative breeding in birds says kin selection has undoubtedly played a central role in how this behavior evolved. Yet helpers can also gain direct benefits from group life, and these benefits can be enough to keep a group together even when its members are not closely related. In one review, 77 percent of the bird species that must breed cooperatively nest in groups that regularly include non-relatives. Cooperative breeding is a common strategy in dry regions of Africa and Australia.

The most common route to cooperative breeding is delayed dispersal, in which young stay with their parents instead of leaving. One idea for why young birds stay and help is habitat saturation: the better territories are already filled by established breeders. Beavers usually live in family groups of up to 8 related beavers, and young beavers stay with their parents for up to 2 years, helping with infant care, food collection and dam building. In an African wild dog pack, once pups leave the den they become the responsibility of the whole pack, and pups nurse from other females as well as their mother, while females usually leave their birth pack at 2 1/2 years or older and about half of young males stay with their father's pack.

Wolves test the idea in another way. In Yellowstone, wolf packs are most commonly a breeding pair and their offspring from several years, though unrelated wolves may also join a pack, so a pack is not always all relatives. Older wolf siblings also take part in pup care and feeding, and kin selection is probably the best explanation, while the positive influence of helpers was strongest for small packs. Yellowstone wolf pups are generally weaned at 5 to 9 weeks old and then fed by various pack members through meat regurgitation, and pack members bring food to the wolf mother and her small pups, so she does not have to leave the den. A Smithsonian National Zoo page says a wolf pack's mother and father are teaching the rest of the pack how to hunt, survive and mark territory. Most young wolves leave their birth pack when they are between 1 and 3 years old, but some stay.

Meerkats show how a group can work when only one female breeds. Researchers with the Kalahari Meerkat Project have followed one meerkat group for around thirty years, as of November 2026. In a meerkat group, one dominant female monopolises reproduction, and the other group members help raise her pups. When a dominant female meerkat dies, the oldest subordinate female, normally one of her daughters, takes her place. Helpers babysit pups for a day at a time and bring them food until the pups are three months old, and they take turns, because a babysitter cannot eat while on duty and goes a whole day without food.

Sharing food can reach beyond relatives. Vampire bats share blood meals with relatives and non-relatives alike. A study of vampire bats recorded food sharing from 2010 to 2014 and also made individual bats fast for 24 hours to see who would feed them. In the study, vampire bats that were more generous were fed more when they failed to find food, and a vampire bat that misses two nightly meals in a row will starve, which is why sharing is like an insurance policy. Lion prides are described as fission-fusion societies, in which members come and go and are rarely all together at once, and in lion prides related females tend to have cubs at about the same time and nurse each other's cubs; cub deaths are lowest when they do. Cubs born in a lion pride are twice as likely to survive as cubs born to a lioness on her own.

Orcas raise a different question: why would a female live long after her breeding years? Scientists studying resident killer whales found that post-menopausal grandmothers improve the chances of survival for their grand-calves, and the study suggests that grandmothers who are still breeding cannot give the same support as grandmothers who no longer breed. Scientists think grandmother orcas may have evolved to live past their breeding years to help raise their grandcalves. Orca mothers teach their calves to hunt, and orca pods pass hunting methods and dialects down the generations, as orcas teach younger pod members through apprenticeship, and skills in hunting and parenting are among the skills taught. An orca pod's dialect has been shown to stay the same in a pod for up to six generations.

Jane Goodall started the Gombe chimpanzee study in 1960, and as of November 2026 it is described as the longest-running study of wild chimpanzees. The Gombe studies have followed generations of chimpanzee families. Tanzanian field assistants record extremely detailed observations on paper, and the same methods continue today. If a young chimpanzee's mother dies, older siblings will often take over the care of a younger, weaned sibling. Researchers in Taï forest, Ivory Coast, reported 18 cases of orphaned chimpanzees being adopted by group members; half were adopted by males, and only one of those proved to be the father. Adoptions by adult chimpanzees can last for years and involve extensive care for the orphans.

Elephants show how much a long-term record can reveal. Elephant calves stay close to their mothers, and other elephants in the herd help look after them, and the leader of an African elephant herd is the matriarch, usually the oldest and most experienced female. Since 1972, researchers in Amboseli, Kenya, have followed the lives of individually known wild elephants, and its partners describe the population as the best-known elephant population on Earth, because each elephant is recognized individually, as of November 2026. When an elephant gives birth, she moves away from the herd; when they return, all herd members inspect the new calf thoroughly. A 2016 study found that Asian elephant families are less cohesive than African ones and seem to lack a clear matriarch, while in the same study African savanna elephants showed clear dominance patterns with a clear matriarch. Female Asian elephants stay in the family unit for their whole lives, while males leave when they mature, and elephant calves are weaned slowly, and they may still drink their mother's milk at up to three years old.

Parental care takes many forms. Dolphin calves develop signature whistles when only about a month old, which helps them stay in contact with their mothers. Dolphins help sick, hurt or young group members by taking turns pushing them to the surface to breathe. Male sea otters do not provide any care to their offspring, and pups remain with their mother for about 5 to 6 months. In clownfish, a male and a female and several young may live together in one anemone, and the male does most of the egg care. Every flamingo parent can make crop milk, but no parent will feed a chick other than its own.

Words to know

• eusocial: fully cooperative
• dispersal: moving away
• generations: family age groups
• subordinate: lower-ranking
• apprenticeship: learning from experts
• cohesive: sticking together