Researchers Teach Bonobos To Create, Use Tools To Retrieve Food
Lawrence LeBlond for redOrbit.com – Your Universe Online
Bonobos have recently had their DNA mapped by scientists, revealing they are much closer genetically to us than previously believed. Perhaps this striking similarity these gentle beasts share with us is no more evident than when it comes to their capability to learn tasks such as learning sign language and creating tools.
Researchers from the University of Haifa in Israel have found that bonobos can learn to make stone tools just like early humans did. One bonobo, Kanzi, a 30-year-old male, has continued to impress researchers with his skills, after producing a variety of flint-like tools to break open wooden logs or to dig up dirt to get to food.
Eviatar Nevo and colleagues sealed food in logs and watched as Kanzi and another bonobo — Pan-Banisha — attempted to retrieve the food.
Pan-Banisha acted as expected — picking up the log and smashing it onto the ground to get to the food inside; Kanzi, took a much different approach.
The Guardian reports that after some training in flint knapping, Kanzi began using small flakes of stone for drilling or scraping, and larger ones as an axe or wedge. He used the tools on the weak areas of the log: the glued slits the researchers had created when sealing the food inside.
When it came to digging, Kanzi implemented a variety of modified stone tools and flint nodules, using them as shovels to get to the food. In total, Kanzi used 156 tools to get to his food. The experiment mimics the conditions that chimps would find in the wild and also mimics scenarios that early humans would encounter in their quest for food. It has long been known that early humans needed to use stone tools to break open bones to get to the marrow inside.
Nevo said both Kanzi and Pan-Banisha had been taught to knap flint flakes in the early 1990s, holding a stone core in one hand and using another as a hammer. But only Kanzi perfected the taught skills to retrieve food from sealed logs. Using the wide array of tools, he was able to get food out of 24 logs, while Pan-Banisha was only able to break open two.
“To accomplish these activities, [Kanzi] produced and used a wider variety of tool types than hitherto reported, with more complex uses, which formed wear patterns very similar to those produced by early [humans],” said the researchers. They speculate that the potential for tool use existed in the common ancestor of chimps and humans.
While tool use has been observed in other animal species, this has been the first time researchers have actually observed animals making and using tools to the same degree of sophistication as our early ancestors.
The researchers say it remains unclear if all bonobos possess similar skills. If so, it could fuel the debate over whether the use of stone tools first occurred in early human culture, or if perhaps some primates had been using the technology long before hominids. Since Kanzi and Pan had been taught to use and create tools, most experts would probably concur that the technology is not inherent in bonobos and other primates.
Kanzi could perhaps be a special case, the researchers note. Raised in a specialized environment, with frequent human contact, Kanzi has advantages that would not exist in the wild.
Nevo and colleagues published their findings in the journal Proceedings of the National Academy of Sciences.