Terrified chimpanzees catch insects that are parasitic on their body to eat to cure diseases

Loango National Park in Gabon recently provided a backdrop for researchers to observe a sight rarely seen in nature: chimpanzees applying insects to their injuries.
The behavior—a unique demonstration of potentially advanced cultural activity—suggests that the primate species may have developed longstanding health-related behaviors that are shared among members of tight-knit groups.
The research team has been collecting data & they have filmed incredible scenes, such as chimpanzees attacking lowland gorillas, even ᴋɪʟʟɪпɡ and eating young ones. The team also observed the chimps working together, using branches to dig out honey in underground beehives.

In February 2022, the scientists published their biggest discovery yet: Chimpanzees deliberately treat their own wounds and those of their group using an unknown species of insect. It’s the first time the behavior has been scientifically observed in the great ape.

Michael Huffman, a primatologist and professor at Kyoto University, is one of the pioneers of research into animal self-medication, a field known as zoopharmacognosy. He observed decades ago that wild worm-infested chimpanzees swallowed the inner stem tissue of the African shrub Vernonia amygdalina. The plant contains anti-parasitic agents and is also used by local people to treat intestinal pain.

When infested with roundworms, bonobos and gorillas swallow rough, hairy plant parts that can combat against parasites. At the same time, the bristly hairs of the plants increase intestinal activity and carry away the worms. Several years ago, scientists also discovered that orangutans in Borneo were treating themselves with dragon tree extract.
Alessandra Mascaro, an evolutionary biologist with Ozouga and leader of the February study, first noticed in 2019 that the Rekambo chimpanzees seemed to treat their injuries. She watched a video clip of female chimpanzee applying a recently caught insect to an open wound on her son. A short time later the mother carefully removed the remains of the insect. The behavior looked like wound care.

Deep in the forest in Loango, Deschner watched as Cesar, a chimpanzee carrying coconut plums, was visited by two males. From about 20 feet away, he saw one of the males had a large laceration on his left thigh and two open spots on his back. The second of the two males was also wounded, his wrist bleeding.
A violent altercation apparently broke out the night before, likely caused by Pandi, the alpha male. After an absence of several days, Pandi rejoined the group, which may have increased tension among the males.
The next morning, I observed the chimpanzees groom each other’s fur. When the animals parted, I followed Thea, one of the apes that visited Cesar the day before and was still injured. It seemed from his facial expressions that his injured leg was bothering him—he inspected the wound with his fingers, and his eyes scanned the surrounding vegetation, as if he were looking for something.

Like a flash, Thea’s right hand reaches into the bushes. He catches an insect, maybe a fly, sitting on the underside of a leaf. He puts the animal in his mouth, lightly crushing it with his lips. He then carefully applies the resulting mush to his flesh wound, stroking it back and forth with his fingertips. He repeats the procedure a few more times before finally cleaning the wound with his fingers.
Three days later, I observed another instance of insect medication. This time it was another male who caught an insect and applied it to one of Thea’s wounds on his back. This behavior signaled to the scientists that, even beyond medicating each other, chimpanzees understand the well-being of others. It may be considered prosocial behavior, which scientists believe requires more complex cognitive abilities.

Whether these findings hold deep scientific meaning or are instead a mere behavioral coincidence remains to be seen. Humans, of course, are also known to do strange things—some proven, but many not—to pursue optimal health and wellness. Chimpanzees behaving the same way would be another thing we have in common with our closest living relatives.