Wild chimpanzees and gorillas can develop enduring, cordial relationships that continue for many years

Chimpanzees and gorillas create friendships, some of which last for at least 20 years, according to a groundbreaking new study

We are aware that many gorillas and chimpanzees are ferociously territorial. Both species will protect their home ranges against invading tribes. Members of other groups that intrude into chimpanzee territory are often killed. Furthermore, researchers discovered that a troop of chimpanzees in Gabon had killed newborn gorillas between 2014 and 2018 and even observed a mother chimpanzee eating an infant gorilla.

With the aid of more than 20 years of data from the Nouabalé-Ndoki National Park in the Republic of Congo, the first study

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of its sort was able to see such long-lasting, peaceful relationships between apes. Unexpectedly, the latest study demonstrates that the two ape species occasionally become long term buddies. It's amazing how these animals may coexist peacefully in one place for a long time while becoming food for one another in another.

Curiously, male primates in their early adulthood have a tendency to be more gregarious and inquisitive than other colony members. Young male apes would frequently seek out specific members of the other species to play with, sometimes traveling great distances (over 300 meters) by themselves to do so, according to the new study. It might be dangerous to mix with members of other groups or species. But rather than being on the attack, both species were at ease with one another. The study also discovered that female chimpanzee and gorillas with young offspring formed bonds with one another, as did all age groups. Even chimpanzees have been observed imitating the traditional gorilla chestbeat. When they came into contact, neither species ever sounded an alarm.

The majority of the friendly contacts that scientists observed in the Republic of Congo involved chimpanzees and gorillas grazing in fig and other fruit trees, which are common diets for both species. Figs are a valuable resource that are high in energy. Fig trees only produce fruit for four to five days. Fruiting is also asynchronous. Perhaps it is more advantageous for gorillas or chimpanzees to tolerate one another rather to expend energy chasing one another away when they discover ripe ones. They might also get an advantage by pooling their expertise or by being nearby so they can hear what the others are doing. Gorillas typically consume significantly less fruit than chimpanzees do. However, these gorillas in the Republic of Congo consume more fruit than usual, which could contribute to the explanation for their exceptionally friendly behavior toward the neighborhood chimps.

Additionally, there are advantages to partnership-based protection. As both species are preyed upon by leopards, it is advantageous to have as many eyes peeled for danger as you can. Even the predator alarm cries of the other species were heard by both species. They exchanged knowledge about prey locations and predators. Other species cooperate with one another to avoid predators. Each year, hundreds of antelope, wildebeests, and zebra travel together through Tanzania and Kenya in search of good grazing and secure locations to breed. We also observe coalitions between other monkey species, such as the putty-nosed and Diana monkeys of the Taï National Park in Ivory Coast, West Africa. These alliances typically serve to boost the likelihood of predator detection or feeding chances.

These findings might provide hints as to how humans may have developed. Despite similar overlaps in diet and competition, some ancient human species may have displayed interspecies tolerance and friendships. There have been discovered hybrid human skeletons. Human stress levels can be decreased by friendships and having a pet can improve mental health. Therefore, it would be interesting to find out if apes also benefit from having a friend from a different species.

These interactions might be more frequent than has been indicated, for all we know. Researchers frequently only examine one or the other species in areas where chimpanzees and gorillas coexist in the same habitat. Species that are not accustomed to human contact frequently flee when they see the research crew. Before a species becomes accustomed to people, researchers frequently study with them for years.

On the IUCN Red List of Threatened Species, chimpanzees are categorized as endangered, whereas gorillas are categorized as critically endangered. The study demonstrates how unpredictable our close relatives are and how crucial it is to protect nature in order to prevent the loss of their unique behaviors before we even become aware of them.

1. Sanz, C. M., Strait, D., Eyana Ayina, C., Massamba, J. M., Ebombi, T. F., Ndassoba Kialiema, S., Ngoteni, D., Mbebouti, G., Koni Boue, D. R., Brogan, S., Funkhouser, J. A., & Morgan, D. B. (2022). Interspecific interactions between sympatric apes. IScience, 25(10), 105059. https://doi.org/10.1016/j.isci.2022.105059