Monkey business – It’s not what you know, but who you know!

Social networks shape monkey “culture”

A new study, published in Current Biology, shows that squirrel monkeys who are at the heart of their social group pick up innovations first, and are more likely to acquire new cultural variations in behaviour like novel foraging techniques.

Dr Nicolas Claidière, Ms Emily Messer and Professor Andrew Whiten of the University of St Andrews in collaboration with Dr Will Hoppitt of Anglia Ruskin University studied both our East and West squirrel monkeys. They examined their social networks by recording who spent time with whom when the monkeys were in the vicinity of an “artificial fruit” that could be used to obtain food rewards by using two different techniques, lift or pivot (Figure 1).

lift and pivot photo

Sophisticated statistical analysis of this information revealed the details of the monkeys’ social networks which helped the researchers visualize which monkeys were at the heart of the network and which were more peripheral (Figure 2). Each monkey was rated on a measure of their ‘centrality’ within the group. social network red vs blue

Boa the alpha male in the East group was briefly separated and trained how to use the lift technique and his equivalent, Rio in the West group was trained to use the pivot technique, they were then reunited with their respective groups.

The scientists found that monkeys who were well-connected were the most likely to successfully pick up the new technique seeded in their group. They were also more likely to acquire the lift technique in the group seeded with ‘lift’, versus the pivot technique in the group seeded with ‘pivot’, so the alpha males were truly the hubs of these two different monkey ‘cultures’.

Professor Whiten, from the University of St Andrews, said: “Our study shows that innovations do not just spread randomly in primate groups, but as in humans, are shaped by the monkeys’ social networks”.

Dr Claidiere said: “Research interest in social learning and social network analysis has surged in recent years, and our results are likely to stimulate further research on the spread of innovations in animal social networks.

“We suspect that our focus on a social network relevant to the diffusion of foraging innovations can explain why we found an effect of the network centrality of individuals on their learning.

“Previous research has focused on other relationships, like who grooms whom, which may not correlate with the monkeys’ observational learning in the same way”.

Emily Messer, noted another aspect of the study. “We also found that maternal relationships explained parts of the social network, so some of the diffusion of the new foraging habits were also probably reflecting an emphasis on learning within families,” she said.

Click here to lead you to the abstract of the article in Current Biology





I’ll have what she’s having – Vervet Monkey Conformity Study

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University of St Andrews researchers Dr Erica van de Waal and Professor Andrew Whiten and Christèle Borgeaud of the University of Neuchâtel have just published in the journal Science about the ability of vervet monkeys to conform to local feeding traditions.

In Living Links and Budongo Trail here in Edinburgh Zoo we do multiple studies on culture and how our primates can learn from each other, however doing this in the wild can be far more challenging, a challenge that Erica, Andy and Christèle overcame with a beautifully precise and effective experiment.

Like many species, vervet monkey infants learn a lot about life from watching their mothers, especially in instances of food choice. In this study four groups of vervet monkeys (total of 109 monkeys) in the Mawana private game reserve in South Africa were introduced to two different colours of corn.

Two groups were trained to eat pink corn and two groups were trained to eat the blue. This training phase was accomplished by making the ‘unpreferred’ food colour choice taste bitter by using aloe extracts from local plants. Approximately 4-6 months after the initial training, the corn was reintroduced to the groups with neither of the coloured corn being treated, thus making both palatable options.

Interesting the monkeys remembered which was their preferred colour choice and infants that had not seen coloured corn before only ate the same colour corn as their mothers did. In fact some of the infants sat the box of the unpreferred coloured corn to eat the ‘right’ colour, says Andy Whiten.

Not only do infant vervet monkeys adopt the ‘right’ colour corn from watching their mothers, males that emigrate to new groups will conform to eat the same colour corn as their new community. For example Groot was part of a group that was trained to eat the blue corn, as all male vervets that reach sexual maturity do he left his group to find another to be part of. When he arrived he saw that they were eating the pink corn, after a brief amount of time watching them he then joined in to eat the pink corn too.

By changing his preconceived ideas on what is appropriate to eat Groot could benefit from the new groups’ local knowledge. Professor Whiten said “It may make sense in nature, where the knowledge of the locals is often the best guide to what are the optimal behaviours in their environment”, thus the “when-in-Rome” mentality makes sense.

There was one exception in the study, a male named Lekker emigrated and immediately became the dominant male of new troop and he did not adopt their feeding preferences. This then created more questions. Did he not take on their traditions because he was dominant and felt no need to adopt the social conformity, or was he just stubbornly set in his ways? Will his new group then conform to what he eats? Since this only happened in one case, more research is required to gain further insight into social status and conformity in vervet monkeys.


van de Waal, E., Borgeaud, C., and Whiten, A. (2013). Potent Social Learning and Conformity Shape a Wild Primate’s Foraging Decisions. Science 340, 483-485.


Getting Acquainted

Study of a Chimpanzee Integration and their Social Networks

chimp aquaintance edit

Since mid 2012 Living Links and the Budongo Trail at Edinburgh Zoo officially became a research consortium. Dr Katie Slocombe of SPRG is the Scientific Director of the Budongo Chimpanzee Research Centre and has a long standing research interest in Edinburgh Zoo’s chimpanzees as well as the chimpanzees in the Budongo forest in Uganda.

Over the years Katie and her colleagues have had the opportunity to conduct multiple studies with our chimpanzees and recently one of these projects has been published in the American Journal of Primatology.

Schel, M.A., Rawlings, B., Claidiere, N., Wilke, C, Wathan, J, Richardson, J, Pearson, S, Herrelko, E, Whiten,  A., and Slocombe, K (2012). Network Analysis of Social Changes in a Captive Chimpanzee Community Following the Successful Integration of Two Adult Groups. American Journal of Primatology 00:1-13.

In May 2010, a new group of chimpanzees from Beekse Bergen Safari Park (Netherlands) arrived to the Budongo Trail, and these chimps were to be introduced to the existing population inhabiting this enclosure. Over the course of 3 months the new arrivals were successfully integrated with the original population.

To aid introductions the Budongo Trail had been designed in such a way that the keepers were able to slowly introduce the chimps to each other by using a multi-pod system (Figure 1). The introductions were conducted at the pace that was dictated by the chimpanzees’ behaviours towards each other while they were physically separated. The keepers’ expertise knowledge of the individuals and their behaviour was key to the successful integration. Table 1 depicts the demographics of the individuals being introduced and Figure 2 shows the process of the integration.

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Fig. 1 – An enclosure map depicting the multi-pod system and the outdoor enclosure area.

Table 1 – Demographic information of the chimpanzees.

table 1 demographics of chimps

chimp integration colour

Fig 2. Illustration of the process of integration of individuals into the third mixed group. An orange shaded cell indicates that individuals left their original group and became part of the mixed group. The dominant males from each group (CL,PA,KD and Q) were introduced last.

In the paper the authors discuss the complexities of integrating two unrelated captive chimpanzee groups and they monitor the group dynamics throughout the integration process with the use of Social Network Analysis (SNA). SNA uses associations (eg. nearest neighbour) and interactions (eg. grooming) data to create a graphic representation (sociogram) of the social relationships within the group (Figure 3).

Sociogram illustration jul - dec

apr - oct 2011

Fig 3 – Sociograms illustrating association patterns from the early and latter periods of integration. Males are shown as blue squares and females as pink circles. Edinburgh chimp names are highlighted in red and the Beekse Bergen chimps shown in yellow. The thickness of the link represents the strength of the association between two individuals and the size of the node represents how well connected that individual is within the entire network .

The sociograms show that in the early period of integration Edith, a 13 year old female from the Beekse Bergen group, had the strongest cross group associations, whereas in the latter period it was Kindia, a high-ranking 12 year old Edinburgh male.

The SNA data that has been collected and shown for this chimpanzee group is on-going so we may continue to monitor the slow process of social integration between two new chimpanzee groups. As you can see from the sociogram there is still a tendency for the chimps to associate with their original group members even though they have been living in the same large enclosure for more than a year. Over time will we see a more even mix of the two sub populations or will they continue to rely on old coalitions?

This research not only allows us a peek at the complexity of chimpanzee social systems but it may also be helpful in making welfare focused animal management choices. If we know the connectivity of each individual in the group we can then make predictions on how removals/additions to that population may play out, along with planning which individuals may need other individuals for social support in new situations.

For information about another chimpanzee project in the Budongo Trail please see a video interview with Katie about studying chimpanzee communication.

For more information on chimpanzee studies in the wild visit the Budongo Conservation Field Station site.