Helping can be tested with small tasks. An adult hung clothes on a line. He dropped a clothes peg that he could not reach. Toddlers who were 18 months old helped a grown-up they had never met. They rarely helped in control conditions. In those, the grown-up did not need help. Young chimpanzees also helped a person who was reaching for something. Nobody asked or rewarded any of them for helping.

A free rat will open the door of a trap. It lets out a rat from its own cage. That rat is stuck inside. The researchers did not train the rats. A rat was as likely to free its trapped cagemate first as to open a container of chocolate. A free rat acted more upset when its cagemate was trapped. It was as if it picked up the cagemate's distress. Empathy is sensing and sharing what another person is feeling.

In a study, pet dogs went up to a crying person. They went to a crying stranger, not only to their owner. Asian elephants comfort other elephants that are upset. They use touch and sounds. An elephant may put its trunk in another elephant's mouth to calm it. A researcher compared this to a handshake or hug. As of November 2026, a 2014 study gave the first scientific evidence that elephants console one another.

Vampire bats form strong bonds with their colony mates. Some unrelated bats have traveled together for more than ten years. Vampire bats can share some of their blood meal with another bat. A bat that found no food can beg for blood. A small amount lets it live and hunt another day. Grooming is mostly linked with food sharing. In some pairs, it eventually gave way to food sharing.

Giving has been studied in groups. Here are three findings. In one experiment, one person's generosity spread to three people and then to nine. In experiments, generous behavior spread through a group. So did stingy behavior. Doing something kind for another person can make you feel happier. That one is about the giver.

Words to know

• empathy: sharing feelings
• distress: upset feeling
• grooming: cleaning fur
• stingy: not giving
• console: comfort

The short version

Studies have found that toddlers, chimpanzees, rats, vampire bats, elephants and dogs help or comfort others. A free rat will open a trap door to let out a rat from its own cage, and the researchers did not train the rats. In experiments, generous behavior spread through a group, and so did stingy behavior.

Quick facts

• A free rat opened a trap door to let out a rat from its own cage.
• Toddlers who were 18 months old helped a grown-up they had never met.
• Vampire bats form strong bonds with their colony mates.
• Pet dogs went up to a person who was crying.
• One person's generosity spread to three people and then to nine.