The bonobo, often called the pygmy chimpanzee, is one of our two closest living relatives, alongside the common chimpanzee. Found exclusively in the dense, humid rainforests of the Congo Basin in the Democratic Republic of the Congo, the bonobo is known for its peaceful, female-centered social structure. The question of whether bonobos eat meat is important because their sister species, the chimpanzee, is a well-documented hunter. Understanding the bonobo’s diet is key to grasping the full spectrum of behaviors in the genus Pan.
The Primarily Frugivorous Diet
Bonobos are classified as primarily frugivorous, meaning their diet is overwhelmingly centered on fruit. Fruit makes up a majority of their daily intake, though the exact proportion varies by location and season, ranging from 57% to as high as 90% when abundant.
They supplement their meals with other plant matter. These items include leaves, leaf petioles, seeds, flowers, pith, and shoots of terrestrial herbaceous vegetation. This non-fruit matter, such as African ginger and arrowroot, provides protein and nutrients. Stable isotope analysis consistently indicates that the overall contribution of animal protein to their total caloric intake is marginal.
How Bonobos Acquire Animal Protein
Although the bonobo diet is heavily plant-based, they are technically omnivores and consume animal protein. The most common animal food is invertebrates, such as insects, larvae, earthworms, and millipedes. This consumption is typically opportunistic, occurring while foraging for plants rather than through specialized hunting efforts.
The consumption of vertebrates, or meat, does happen but is observed much less frequently than in chimpanzees, although recent studies suggest it may be more common than previously thought. Bonobos have been documented preying on small forest antelopes, such as duikers, as well as rodents and even other primates like monkeys. The acquisition of these larger prey items is often less about complex, coordinated hunting and more about capitalizing on vulnerability, such as seizing a duiker calf hidden in vegetation.
In some bonobo communities, females have been observed leading hunts and successfully defending their bounty from males. Observations of bonobos attempting to hunt vertebrates are rare, and they sometimes exhibit fear or hesitation when encountering live prey, suggesting a less ingrained predatory drive.
Comparing Bonobo and Chimpanzee Feeding Strategies
The feeding strategies of bonobos contrast with those of the common chimpanzee, particularly concerning the pursuit and consumption of meat. Chimpanzees are well-known for their strategic, coordinated group hunts, often targeting monkeys, such as red colobus monkeys. This behavior is male-dominated, and the subsequent sharing of meat plays a role in the social hierarchy of chimpanzee communities.
While bonobos also consume meat, their hunting behavior is generally less frequent and lacks the same level of male-led coordination seen in many chimpanzee populations. In bonobo society, which is female-centered, females often control the meat when it is acquired, and sharing patterns can differ from the male-centered sharing observed in chimpanzees. This difference in predatory behavior was once considered a defining trait between the two species, often linked to the bonobo’s more peaceful social structure.
However, the perceived gap in meat-eating frequency has narrowed with more recent, sustained observations of bonobos in the wild. Some studies have found that bonobos in certain regions consume and share meat at rates comparable to chimpanzees, demonstrating that the frequency of meat consumption can vary significantly across different bonobo groups. These variations in prey preference and hunting frequency may be influenced by local ecological factors and even reflect different cultural traditions between bon groups.