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

vervet-monkeys6 copy







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.


Royal Society of Edinburgh (RSE) honours Prof Andy Whiten

andy medal newsProfessor Andy Whiten the Director of Living Links has been awarded the Sir James Black Prize and Medal.

He has been bestowed this honour due to his outstanding work in primatology and his innovations within the field of social learning and the cultural transmission of behaviour.

Later on this year he will be giving a guest lecture for RSE entitled “Social Learning and the Cultural Transmission of Behaviour in Human and Non-human Animals: A ‘Second Inheritance System’ in Biology.”

As soon as we know the date and location for this lecture we will post it up here on the Living Links website.

Dung Days at the Zoo

dung day blog picture




As part of the Edinburgh International Science Festival we are running Dung Days at the zoo. There are many activities for our visitors to take part in to learn all about poo!

A few of the research projects here in Living Links have involved using coloured glitter to help us determine which monkey left which poo. This has been helpful in studies looking at hormone levels and in our research into colour vision.

During Dung Days our visitors can create their own capuchin glitters poos!



Chimp Challenge – Memory Test

chimp challenge




There is a new interactive in the Living Links Centre. Our guests can play a game to find out if they have a better memory than a chimpanzee. Tetsuro Matsuzawa from Kyoto University Primate Research Institute has demonstrated that chimpanzees have an extremely good working memory and are capable of completing a number organising task at greater speeds and accuracy than humans.

Justin Quillinan and Sean Roberts two PhD students from the University of Edinburgh want to find out if with practice can humans become just as good as chimpanzees at this activity?

You can play this it at home!


Warning this game is highly addictive

To find out more about Justin and Sean’s research you can follow their blog.


Reconstructing the Evolution of Cognition – Free Lecture

dr josep call





St Andrew’s University is delighted to announce that Dr Josep Call will be presenting the Irvine Memorial Medal Lecture on Friday the 8th of March 2013 at 5:15pm in School III, St Salvador’s Quad, St Andrews University.

All are welcome to attend this free lecture.

Dr Josep Call the Director of the Wolfgang Kohler Primate Research Centre, Max Planck Institute for Evolutionary Anthropology in Leipzig will be presenting on what makes us human and how has our cognition evolved. To explore these concepts Dr Call compares the behaviour and cognition of multiple species taking into account their evolutionary relationships and ecologies in order to enlighten us on how and why humans have evolved the way we have.

Does a Capuchin’s Openness to Participate Bias our Science?

When studying animals in the wild or in captivity it is very easy to unintentionally create selection biases even when we are aware of them and try to collect data in a random fashion. One particular factor that may cause a bias is the personality of our animals.

Personality is defined as – consistent differences in an individual’s behaviour and decision making over time. Thus if we are studying animal cognition the animal’s personality will have an impact on how we get and interpret the results of our studies.

Selection biases may occur for variety of different reasons

  1. Self-selection of study subjects – The animal chooses to take part.
  2. Targeting a specific area/population
  3. Ending a study once you get the desired result
  4. Excluding data on arbitrary grounds.

A recent study by Blake Morton, Prof Phyllis Lee and Prof Hannah Buchanan-Smith of Stirling University tested to see if the capuchins at Living Links had any specific personality traits and if so did that affect how much they participated in research and also how well they performed.

The research indicated that our capuchins do have at least 5 different personality dimensions, shown in the table below.

morton et al table

The researchers then examined if these personalities affected their participation and performance in our studies so they created two tasks for the monkeys.

Task 1 The monkeys had to choose which cubicle to enter. If they chose the one with the reward in front of it they received the reward. If they chose the one without a reward they did not receive anything.

task 1 pic 1

Task 2 – The monkeys had to choose which cubicle to enter. If they chose the one with the larger cup in front of it they received the reward. If they chose the one with the smaller cup they did not receive anything.

task 2 pic 1


In both tasks the monkeys that scored higher on ‘openness’ and lower on ‘assertiveness’ performed better at the tasks and were also more likely to participate in the trials.

This is a very interesting result so we decided to ask Blake a few questions about the study.

Science Communication Officer (SCO) – Is there any way to avoid a personality selection bias in cognitive studies?

Blake – One possibility would be to classify subjects according to their personalities, then test for differences in task performance within those groupings. However, most studies of animal cognition do not have access to large study populations, and must therefore rely on using small sample sizes. At this point in time, we encourage researchers to consistently report the existence (or lack thereof) of a personality bias in subjects selected for testing.

SCO – Why do ‘open’ individuals perform better than ‘assertive’ individuals?

Blake – Open individuals are typically more curious and willing to engage in tasks. As a consequence, they often perform better than less Open individuals. As for Assertiveness, one intriguing possibility, which we discuss in our paper, is that more aggressive individuals (called ‘Assertive’ in our study) have a tendency to emphasize speed over accuracy when making decisions. Thus, as a consequence of such hasty decision-making, aggressive individuals may be more likely to score incorrectly on trials. To formerly test this latter possibility, however, further research on the Living Links capuchins will be necessary.

SCO – Are there any cognitive studies that would benefit from having a bias towards ‘open’ individuals?

Blake – Based on our study and others, individuals that score higher on Open traits (e.g. curious, active) typically are more willing to engage in experimental research. As a consequence, they generally learn faster and perform better on tasks compared to less Open individuals. Thus, from a logistical point of view, yes, a study might benefit from having a bias towards more Open individuals because it potentially means that less training/testing is needed. However, as we discuss in the paper, caution should be used when comparing data to other studies.



SciLogs Blog about Living Links Science Engagement

SEZ at Living Links

In early 2012 Dr Mark Bowler, Prof Hannah Buchanan-Smith and Prof Andy Whiten published a great article on the assessment of the science engagement that goes on in the Living Links Centre. This article has been well received by many zoo educators and scientists alike.


The article was recently recommended to Matt Shipman who writes for SciLogs – The daily storyline of science. He posted a review on their blog commenting on the benefits of zoos in educating people about science outside of the classroom and lecture theatres.

Click on the link below to read his review!


SPRG Burn Weekend 2013

The Burn weekend has been a long standing SPRG tradition since 1996. This weekend the Burn mansion house in Angus welcomed 42 SPRG members and guests to enjoy a relaxed weekend of fun, talks and a stunning winter walk.


SPRG’s main focus is of course primates however we had an amazing array of talks ranging from primate communication (vocal and gesture) to parrot social bonding and even a talk on the personality and well-being in felids.

Living Links was well represented this weekend with 9 of our team attending and many people that presented had undertaken work at Living Links and/or Budongo Trail.

SPRG programme 2013

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.

budongo trail map

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.

Eye Tracker Trials – Insight to Monkey Minds?





On October 31st, Living Links researchers Dr. Nico Cladiere and Dr. Juan Carlos-Gomez welcomed Jon Ward from Acquity ETS Ltd to trial a Tobii infra-red eye tracking device with our primates. The tracker was trialled with our East group of capuchins, squirrel monkeys and the Budongo Trail chimpanzees.

This type of non-invasive technology has been designed for humans and is well used in a many fields, such as cognitive and developmental psychology, linguistics research, neuropsychology and can also be helpful in diagnostics of mental disorders.

Infra-red eye trackers have been tested with great apes and macaques, but as far as we are aware this is the first time this type of technology has ever been trialled on capuchin and squirrel monkeys.

Our attempts with the squirrel monkeys were promising, but they did not stay still long enough for the tracker to detect their eyes.

The chimpanzees did show some interest in the trials and the machine was able to pick up their eye gaze when they were shown pictures of chimpanzee faces however no data were recorded from the chimps as we were unable to calibrate the machine.  In order for the tracker to work properly it must be calibrated by the study subject following the calibration dot.

The greatest success of proof of concept was with the capuchin Kato (a 7 year old periphery male from the East group). He came into the cubicles, sat in position and easily followed the calibration dot. After he successfully did this he was shown a variety of pictures of other capuchins in his group and some from the West. The photos were of females and males of varying ranks.

Watch the video to see where Kato looked for each of the monkeys. The size of the red dot is indicative of the length of time Kato spent on that point on the screen, the red lines show the pattern of his gaze as it moves.

The eye tracking system is able to display the data in a variety of ways. We can see the length of time spent focusing on one area and track where the gaze goes over time.

This visualisation was created by two trials. The yellow is the first set of tracks and the purple the second. They are numbered so you can see the gaze pattern.

The software is also able to show length of gaze through light and shadow. The longer the monkey stares at one area of a picture the lighter it becomes.









Both Juan and Nico were very impressed by this technology and its potential for countless benefits to the studies here in Living Links. Just from the quick trials we were able to see Kato’s tendency to avoid staring at the eyes of the alpha males and the fact he looked directly at the eyes of the females from the neighbouring group. This type of data can enlighten us on the group dynamics, hierarchies and the ability of our monkeys to recognise individuals. The tool may also be useful in social learning studies as well as the evolutionary development of various cognitive processes.