Unprecedented behavior in chimpanzees surprised scientists

Experts discovered that chimpanzees caught flying insects, pressed them between their lips and then placed them on the wound, repeating it many times as if to treat.

Scientists studied a group of 45 chimpanzees in Loango National Park in Gabon, on the west coast of Africa, from 2005. Between November 2019 and February 2021, they observed 22 chimpanzees with 76. open wound.

In 19 cases, they found chimpanzees engaged in behavior similar to self-medicating wounds with insect "medicines". Some even use this method to heal other children. The new study was published in the journal Current Biology on February 7.

The chimpanzee first captures a flying insect and immobilizes it by pressing between its lips. They place the insect on the wound, moving it with the tips of their fingers. Finally, chimpanzees use their mouths or fingers to take it out. They often put insects in the wound and then remove it again and again.

Chimpanzees place the insect on the wound, moving it with the tips of their fingers.

It's not clear what insects the chimpanzees used, and how specifically it helped heal wounds, the team said. They have only determined that they often use small, dark-colored flying insects. There is no evidence that chimpanzees eat insects. They just use their lips to press the animal and then put it on the wound.

One possible explanation for this behavior is that some insect components may be anti-inflammatory, antiseptic, or just part of the chimpanzee's "local culture," like some healing notions. of human.

Scientists have documented self-healing in animals, for example, dogs and cats eat plants to help vomiting, bears and deer eat medicinal plants, orangutans use plant materials to soothe muscle injuries. But they have never seen mammals other than humans use insects for medicinal purposes.

The team has even seen chimpanzees use this technique on their own. For example, adult female chimpanzee Carol catches insects, giving them to adult male chimpanzees Littlegrey. Littlegrey took the insect between his lips and placed it on the wound. Then, two other chimpanzees also helped it grab the insect, put it on, and move it over the wound.

There are some animals that cooperate with others in a similar way, according to study author Simone Pika, head of the animal perception laboratory at the University of Osnabruck, Germany. "However, we have not known of any other cases in mammals. This is likely a learned behavior that exists only in this group," said Pika.

In some of their social behaviors, cooperation involves an exchange of benefits. For example, grooming helps to remove parasites for another chimpanzee, while also providing an insect meal for itself.

But in the cases where insects were used to cure other diseases of the kind that Pika observed, the chimpanzees received nothing in return. This, she says, suggests they are engaging in an action that increases the "interest of another being" and helps scientists understand more about chimpanzees' social relationships.