Bonobos are one of humanity’s closest living great ape relatives. Found exclusively in the Democratic Republic of Congo, these apes are known for their complex, matriarchal, and peaceful social structure. They demonstrate high intelligence and cognitive abilities, frequently observed in their problem-solving and communication skills. A central question in primatology is whether this species habitually uses tools in their natural environment, a behavior often associated with advanced cognition.
The Current Evidence for Tool Use in the Wild
The scientific consensus is that habitual, complex tool use and manufacture are functionally absent in wild bonobos, especially when compared to other great apes. Observations in their native habitat have documented a very limited repertoire of such behaviors. Only about eight distinct tool-using behaviors have been reported across various long-term field sites.
The minimal tool use observed is rarely for foraging or resource extraction, which is the most common use among tool-using primates. Instances tend to be simple and related to comfort or hygiene. Examples include using a large leaf as a “leaf-umbrella” to shield themselves from rain, using a small stick for dental autogrooming, or scooping water with an emptied plant pod. These marginal cases do not constitute the widespread, population-specific tool cultures seen elsewhere in the ape family.
Bonobo Innovation in Controlled Settings
Despite the scarcity of tool use in the wild, bonobos exhibit a high cognitive capacity for it in controlled or captive environments. Studies show that captive bonobos are equally diverse and capable tool-users as chimpanzees when given the motivation and opportunity. In these experimental settings, bonobos demonstrate the potential for highly complex tool use, often to acquire food rewards.
When presented with tasks requiring planning, bonobos have used stones and antlers as levers, shovels, and daggers to dig for buried food or break open bones. One experiment showed a bonobo striking a long bone with a hammer stone, a technique resembling the early stone tool use of hominins. Furthermore, bonobos have demonstrated the ability to select and save specific tools for later use, indicating foresight and functional understanding of the object’s properties. This confirms that the lack of wild tool use is not due to a deficit in their manipulative skills or cognitive capacity.
Distinguishing Bonobo Tool Use from Chimpanzee Patterns
The difference in tool use between bonobos and chimpanzees is one of the most striking behavioral distinctions between the two species. Wild chimpanzees are renowned for their extensive and varied tool cultures, which exhibit widespread social learning and transmission across different populations. Chimpanzees regularly use tools for extractive foraging, such as using selected sticks for “fishing” for termites or ants, and employing large stones as hammers and anvils for nut-cracking.
Chimpanzee tool use encompasses a broad array of contexts, with over 40 distinct behaviors documented in the wild. Many of these behaviors involve modifying a natural object before use. In stark contrast, wild bonobos lack this widespread, learned material culture, and the few tools they use are rarely modified or used for subsistence. While the cognitive ability for complex tool use is shared, the frequency, context, and reliance on tools for survival differ profoundly in their natural habitats.
Ecological and Social Influences on Behavioral Differences
The prevailing hypotheses suggest that the absence of tool use in wild bonobos stems from a lack of environmental pressure rather than a lack of intelligence. Bonobos inhabit the Congo Basin, a region characterized by stable, resource-rich rainforests with a high abundance of soft fruits and readily available vegetation. This lush environment reduces the necessity for tool-assisted foraging, as food sources do not require complex extraction or processing, such as cracking hard nuts.
The bonobo diet is less reliant on hard-to-access resources compared to some chimpanzee populations, who often face seasonal scarcity or competition for embedded foods. Some research suggests a species difference in the innate predisposition for object manipulation, with young chimpanzees engaging in more object play than bonobos. Therefore, the difference appears to be less about capability and more about motivational factors and ecological necessity.