New PanAf paper: Chimpanzee Ethnography Reveals Unexpected Cultural Diversity

How complex are chimpanzee cultures?
Chimpanzee groups each have their own unique termite fishing cultures

The transmission of cultures from generation-to-generation is only found in a few species besides humans. Chimpanzees are one such species and exhibit a large diversity of cultural and tool use behaviours. Although these behaviours have been well documented at a handful of long term research sites, the true cultural repertoire of chimpanzees across populations is still poorly understood. To better understand this diversity, researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, initiated the ‘Pan African Programme: The Cultured Chimpanzee’ (PanAf) in 2010. Using a standardized protocol, researchers set up camera traps, collected samples and recorded ecological data at over 40 temporary and long-term research sites across Africa.

Prior to this study, termite fishing was thought to occur in only two forms with one or multiple tools, from either above-ground or underground termite nests. By carefully observing the techniques required to termite fish at 10 different sites, lead author Christophe Boesch created a catalogue of behaviours (or ethogram) for each chimpanzee in the study.

What was found was 38 different technical elements making up the various termite fishing techniques, all of which were combined in different ways in each of the chimpanzee communities. In addition, individuals in the same community shared more of the termite fishing technical elements, and unique combinations of the technical elements, when compared to chimpanzees from other groups. 

“The diversity of techniques seen in chimpanzee termite fishing was a huge surprise to me. Not only does each community have a very unique way of fishing, they also combine a number of different elements into specific termite fishing etiquettes” explains Dr. Christophe Boesch “the most striking examples of this are how the Wonga Wongue chimpanzees of Gabon usually lie down on their sides to termite fish, while the Korup chimpanzees in Cameroon lean on their elbows, and the ones from Goualougo in the Republic of Congo sit while fishing”.

Wonga Wongue, Gabon

Korup, Cameroon

Goualougo, R-Congo

Because the communities of chimpanzees live in similar habitats with access to the same resources, ecological differences could mostly be ruled out to explain the observed differences. “This supports the idea that chimpanzees are capable of imitating social techniques in ‘how to termite fish’ which goes beyond alternative explanations such as each individual reinventing termite fishing each time they learn it” explained co-author Ammie Kalan.

Much like in human etiquette, not everything is about increased efficiency but rather about conforming to what the rest of the group is doing. In humans, this is observed in the different chopstick cultures across Asia. “For example, in Thailand and Japan not only are chopsticks somehow shaped differently, but the way they hold them differ as well, and this is very reminiscent of what we see here with chimpanzees. In La Belgique in Cameroon, chimpanzees fashion their stick by opening the fibers to obtain a long brush and then rest the termite-covered stick on their wrist while they eat. On the other hand, at another site in Cameroon called Korup, the chimpanzees do not make a brush at all and use their mouth to shake the inserted stick while it is in the mound”, explains Christophe Boesch.

La Belgique, Cameroon

In humans, cultural variation has been documented in hundreds of different populations which is one explanation for why chimpanzee culture seems so limited in comparison. “What we knew before about chimpanzees came from at most 15 communities” noted co-author Hjalmar Kuehl,  “through the PanAf we have been able to study many more communities and by this we are able to learn more about the richness of chimpanzee diversity and culture and could demonstrate that there is so much more to discover out there.”

Further analyses of videos and other data collected from the PanAf are currently underway. “Termite fishing and other cultural behaviours of wild chimpanzees can be observed first hand by signing onto our citizen science platform Chimp&See”, says co-author Mimi Arandjelovic. At Chimp&See citizen scientists can watch the over 1 million video clips the PanAf has recorded from all across Africa of chimpanzees, gorillas, elephants, buffalo, leopards and many more species. Visit www.chimpandsee.org and you could be a citizen scientist contributing to analyzing data and help with further discoveries in the wild!

citation:
Boesch C, Kalan AK, Mundry R, Arandjelovic M, Pika S, Dieguez P, Ayimisin EA, Barciela A, Coupland C, Egbe VE, Eno-Nku M, Fay JM, Fine D, Hernandez-Aguilar RA, Hermans V, Kadam P, Kambi M, Llana M, Maretti G, Morgan D, Murai M, Neil E, Nicholl S, Ormsby LJ, Orume R, Pacheco L, Piel A, Sanz C, Sciaky L, Stewart FA, Tagg N, Wessling EG, Willie J, Kühl HS (2020) Chimpanzee Ethnography Reveals Unexpected Cultural Diversity. Nature Human Behaviour doi: 10.1038/s41562-020-0890-1
https://www.nature.com/articles/s41562-020-0890-1

• Press release in English
• Pressemitteilung auf Deutsch

Commentary: Chimpanzee termite fishing etiquette

A fantastic commentary on our new paper by Dr. Kathelijne Koops:  Chimpanzee termite fishing etiquette

Summary:
Human culture is unique. Or is it? A new study reveals unexpected cultural diversity in the fine-grained details of chimpanzee termite fishing behaviour. These novel findings shed light on the richness of chimpanzee cultural diversity and reveal a narrower gap between the cultures of humans and other apes

original citation
Boesch C, Kalan AK, Mundry R, Arandjelovic M, Pika S, Dieguez P, Ayimisin EA, Barciela A, Coupland C, Egbe VE, Eno-Nku M, Fay JM, Fine D, Hernandez-Aguilar RA, Hermans V, Kadam P, Kambi M, Llana M, Maretti G, Morgan D, Murai M, Neil E, Nicholl S, Ormsby LJ, Orume R, Pacheco L, Piel A, Sanz C, Sciaky L, Stewart FA, Tagg N, Wessling EG, Willie J, Kühl HS (2020) Chimpanzee Ethnography Reveals Unexpected Cultural Diversity. Nature Human Behaviour doi: 10.1038/s41562-020-0890-1
https://www.nature.com/articles/s41562-020-0890-1

Prof Dr Christophe Boesch talks about chimp culture, the PanAf and citizen science

A new chimpanzee behavioural variant! Algae fishing in Bakoun, Guinea

We began the Pan African Programme: the Cultured Chimpanzee (PanAf) in the hopes of discovering new chimpanzee cultures and cultural variants in previously poorly- and unstudied populations. Earlier this year we documented the occurrence of a new behaviour, chimpanzee accumulative stone throwing, present in four populations in West Africa. Today we are happy to announce the publication of our new study reporting on an new behavioural variant of algae fishing by chimpanzees in Guinea!

We describe the first camera trap footage of algae fishing behaviour at a PanAf temporary research site in Bakoun, Guinea where the tool-use appears quite different from what is known from a nearby long-term chimpanzee site at Bossou, Guinea and also differs from previous reports of rare algae scooping in Congo. 

All age and sex classes of Bakoun chimpanzees were observed to successfully fish for algae in a river, stream or pond using woody branches or twigs as fishing rods. The tools were on average longer and sturdier than the algae fishing tools described at Bossou. 

The freshwater green algae being targeted was of the same genus, Spirogyra, that is fished at Bossou, but grows on the bottom of the river and stream beds and does not collect on the surface as it does at Bossou. As such, the ecology of the particular algae growing at each site may drive the types of tools necessary to harvest the algae. We suggest that the algae likely provides a substantial nutritional benefit to the chimpanzees at Bakoun, especially during the dry season when chimpanzees were observed to fish for up to an hour at the same spot. 

These videos have not yet been up on Chimp&See yet and you can see that one of the limitations of our study was that the chimps from these videos have not yet been identified. We're hoping to have these up sometime in 2017 and look forward to matching some chimps with you then!

Citation:
Boesch C, Kalan AK, Agbor A, Arandjelovic M, Dieguez P, Lapeyre V, Kühl HS (2016) Chimpanzees routinely fish for algae with tools during the dry season in Bakoun, Guinea. American Journal of Primatology doi 10.1002/ajp.22613

Chimpanzee Accumulative Stone Throwing - our 1st PanAf paper!

Our very first PanAfrican Programme: the cultured chimpanzee paper is out today in Scientific Reports!

We have already had some stone throwing videos up on Chimp&See, you can check them out at the #stonethrow tag group! Below is one of our favourites of Dodge demonstrating hurling a rock at an accumulative stone throwing site:

original video can be found at 

http://talk.chimpandsee.org/#/subjects/ACP0005652

You can check out the press release here! (German version here) 

and the original paper here!

Chimpanzee accumulative stone throwing

Abstract of the paper:

The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites.

The PanAf is made up of a network of amazing collaborators who made this paper possible, please check them out at: http://panafrican.eva.mpg.de/english/team.php