When Jane Goodall documented chimpanzees in Uganda using tools for the first time, it rocked the scientific community. Since then, however, chimps are not the only apes to have been found to use implements to their advantage, as orangutans, gorillas, and bonobos have all been discovered using them to some extent, but never to the same degree.
Yet in a two-decade-long study, researchers have found that bonobos may possess the ability to craft as complex tools as their more well-known simian cousins, as they appear to use a technique to crack nuts that may even be more efficient than chimps. This raises the question that the enigmatic bonobo may actually be much more proficient at using tools than previously given credit for, and that studies looking into their ability to do so should be expanded.
The latest piece of research, published in the Journal of Primatology, has been carried out by researchers studying wild-born rehabilitated bonobos living at the Lola ya Bonobo sanctuary in the Democratic Republic of Congo. Rarely has this sister species to the chimpanzee been observed using tools in the wild, but at the sanctuary they have been found to use "hammer" stones to crack nuts.
When analyzing the nut cracking behavior of 18 bonobos over a period of 20 years, researchers found that they displayed tool manipulation and complexity comparable with wild chimpanzees, something never before seen. They used up to fifteen different grips to hold hammer stones, 10 of which had never been seen in any other species of tool-using primate, and showed a clear preference for either right-handed or left-handedness.
In fact, so efficient were the bonobos at getting at the tasty nut kernel, they were even found to crack them at a faster rate than the renowned wild nut-cracking chimps of Bossou. The question then raised is why the apes appear to not practice such behaviors in the wild, or at least so infrequently. Interestingly, gorillas have been found to use tools when in captivity, but rarely do so in the wild. This shows that they may have the cognitive ability to craft implements, but it may be something to do with their environmental access when in their natural habitat that for some reason limits them, for example not having the right food source close to the required sticks.
Something similar could be playing out with the bonobos so far observed in the wild, or it could simply be that not enough detailed studies have been carried out on the apes that live in the remote rainforests of the Democratic Republic of Congo. The researchers think that more analysis should be carried out on the apes, and that perhaps they will be found to be just as handy as their more well-known tool-wielding relatives.