Public Release: 

Research reveals bonobos skillfully cracking nuts with stone hammers like chimpanzees

A first of its kind study from the University of Kent found that wild-born, rehabilitated bonobos (Pan paniscus) can be efficient nut-crackers with a skill level not that different from wild chimpanzees

University of Kent

A first of its kind study from the University of Kent found that wild-born, rehabilitated bonobos (Pan paniscus) can be efficient nut-crackers with a skill level not that different from wild chimpanzees.

Conducted by Johanna Neufuss from the University's School of Anthropology and Conservation, with the results published in the American Journal of Primatology, the research analysed the behaviour of 18 bonobos that have been cracking nuts for at least two decades at the Lola ya Bonobo sanctuary in the Democratic Republic of the Congo.

Unlike chimpanzees - sister species to the bonobo - bonobos rarely use even simple tools in the wild. Only a few studies have reported tool-use in captive bonobos, including their ability to crack nuts, but details of this complex tool-use behaviour have not been documented before.

However, the Kent study has revealed a much greater diversity of manipulative ability than previously considered including fifteen grips to hold hammerstones, ten of which have not been observed in any other nonhuman primates including chimpanzees and capuchin monkeys.

The study showed that bonobos have an exclusive hand preference for using either the right- or left-hand during nut-cracking, with the majority of individuals being right-handed. It also revealed that bonobos demonstrate a hand use strategy when hammering with larger stones, preferring either both hands or one hand/one foot.

Bonobos also actively select the most efficient hammer stones for cracking nuts and, when compared to the renowned nut-cracking chimpanzees of Bossou (Guinea), they also crack significantly more nuts per minute.

It is clear from this study that more future studies on complex tool-use behaviour in bonobos under natural conditions are required, in order to explore the full range of their manipulative and tool-use capabilities. Johanna Neufuss is a PhD student who studies the functional morphology of the hand in extant apes.

###

Nut-cracking behaviour in wild-born, rehabilitated bonobos (Pan paniscus): a comprehensive study of hand-preference, hand grips and efficiency (Johanna Neufuss, Tatyana Humle, Andrea Cremaschi and Tracy L Kivell; University of Kent; DOI: 10.1002/ajp.22589) can be viewed at http://onlinelibrary.wiley.com/doi/10.1002/ajp.22589/full

Images available.

For further information, images and interview requests with Johanna Neufuss contact Kiran Dhaliwal at the University of Kent Press Office.

Tel: 01227 823581

Email: K.K.Dhaliwal@kent.ac.uk

News releases can also be found at http://www.kent.ac.uk/news

University of Kent on Twitter: http://twitter.com/UniKent

Note to editors

Established in 1965, the University of Kent - the UK's European university - now has almost 20,000 students across campuses or study centres at Canterbury, Medway, Tonbridge, Brussels, Paris, Athens and Rome.

It has been ranked: 23rd in the Guardian University Guide 2016; 23rd in the Times and Sunday Times University Guide 2016; and 22nd in the Complete University Guide 2015.

In the Times Higher Education (THE) World University Rankings 2015-16, Kent is in the top 10% of the world's leading universities for international outlook and 66th in its table of the most international universities in the world. The THE also ranked the University as 20th in its 'Table of Tables' 2016.

Kent is ranked 17th in the UK for research intensity (REF 2014). It has world-leading research in all subjects and 97% of its research is deemed by the REF to be of international quality.

In the National Student Survey 2016, Kent achieved the fourth highest score for overall student satisfaction, out of all publicly funded, multi-faculty universities. Along with the universities of East Anglia and Essex, Kent is a member of the Eastern Arc Research Consortium (http://www.kent.ac.uk/about/partnerships/eastern-arc.html).

The University is worth £0.7 billion to the economy of the south east and supports more than 7,800 jobs in the region. Student off-campus spend contributes £293.3m and 2,532 full-time-equivalent jobs to those totals.

In 2014, Kent received its second Queen's Anniversary Prize for Higher and Further Education.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.