Primates are our closest relatives, and study of them is a crucial aspect of evolutionary anthropology. But what can the study of primates teach us about humans, and how do anthropologists go about studying them? We asked UTSC Anthropology Professor Julie Teichroeb – co-author of the latest edition of Primate Behaviour: An Exercise Workbook – for an overview of the study of primate behaviour, its importance, rewards and its challenges.
Why is the study of primates so important to anthropologists? What can we learn from primates about humans and their development?
JT: Anthropology is the study of humanity, and since we are the only remaining living hominin (a branch of bipedal apes), we are very interested in the range of morphology, behaviour, and social organization seen in other nonhuman primate species. Or to put it simply, other primates are our closest cousins among the animals, and the ways that selective pressures in evolution have shaped their bodies, their activities, and their social systems can tell us a lot about how these evolutionary pressures may have acted within the hominin lineage.
What sort of behaviour do you look for? How can you identify and understand different primate behaviour?
JT: All behaviour is interesting to me! Specifically, I am very interested in why individuals make the decisions they do. For instance, two female monkeys in the same group – upon sexual maturity, one female makes the decision to stay and breed in her group of birth, while the other makes the decision to transfer to another group to breed, even though it is risky to move to a new area with unknown resources and individuals. Why? What are the underlying benefits and costs to these females of making these disparate decisions? Did the transferring female move to a home range that is higher quality? Was the alpha male in these females’ group of birth the father of the one that transferred? Perhaps she was avoiding inbreeding. Was the female that transferred lower-ranking than the female that stayed? She could have been seeking a better social situation. Was the mother of the female that stayed still alive in the same group, while the mother of the female that transferred no longer present? This could lead to a strong, long-term coalition for the female that stayed. I love nothing better than working through these sorts of puzzles. The difficulty lies in collecting long-term, unbiased data on individuals that you recognize in the field, along with associated information about the ecology and the environment, and genetic samples to really get at the answers to these types of questions.
How do we go about studying primates? What methods do we use? What are the challenges?
JT: Primates are studied both in captivity and in the wild, and their natural behaviour can be observed or experimental data can be gathered. Collected behavioural data can be correlated to the ecology or to biological samples analyzing physiological information like hormone levels or parasite infections. The methods we use to collect behavioural data underwent a major revision in the 1970s with the publication of a now famous paper by Jeanne Altmann, which pointed out the biased way that data had been collected previously and laid out new sampling techniques. In my opinion, the main challenge in collecting behavioural data is the fact that any observation made is filtered through the eyes and the brain before it is recorded. We have to be very aware that prejudice and interpretation can enter the data record at this point and always strive to be as descriptive as possible.
Can you tell me a little about fieldwork, your experiences studying primates, and whether you got to know any individuals or groups especially well?
JT: During my graduate degrees, over a period of 10 years, I spent two and a half years at the same field site in Ghana called the Boabeng-Fiema Monkey Sanctuary. I studied a population of critically endangered white-thighed colobus (Colobus vellerosus) there. Myself and another researcher were the first to individually recognize these monkeys and I got to know four groups extremely well. It was amazing watching individuals grow, change, and make decisions affecting their reproduction over that time. I, of course, had my favorites, like Wolfy, a goofy looking male that transferred between two of my study groups and never committed infanticide (a common male reproductive strategy in this species), and Grace, an older matriarch who aided all the younger females by caring for, and sometimes rescuing, their infants.
In my post-doc, I started to work at Lake Nabugabo in Uganda and I've spent about a year and a half at that field site too over the last nine years. Along with my field assistants and students, we recognize about 140 Rwenzori Angolan colobus (Colobus angolensis ruwenzorii) and 50 vervet monkeys (Chlorocebus pygerythrus). There are some monkeys that really stand out as exceptional. Like the star of several of my foraging experiments, an old vervet male named Viper; Patch and Limpy, the two most amazing vervet moms I've ever known; or Jamong and Janko, who like some other Rwenzori colobus males, bond tightly to one another and often carry infants. I feel so privileged that these animals have allowed me to observe them and share in their life experiences.
How does your book build upon previous editions?
JT: The original edition of Primate Behavior: An Exercise Workbook was written by my undergraduate and Masters supervisor at the University of Calgary, James Paterson, and published in 1994. It was quickly adopted in many classes that taught observation methods to students. I used this book as an undergraduate, as did Lisa Corewyn, my co-author, and it was important in teaching us many of the fundamentals of observing animal behaviour. Jim Paterson updated the book in 2000 by adding some field exercises like phenology and ecological surveys. In the new edition, 21 years after the second, Lisa and I worked to keep all the fundamentals that we loved about the original book but we updated everything, which was especially important in terms of the availability of new technologies. We added new chapters on biological and morphological sampling, software and methods of data storage, compilation, and analyses, and measures of social association, and we significantly expanded the statistics chapter. The book is now aimed not just at undergraduates first learning methods of observation but also at graduate students, attempting their first field studies.
What advice would you give to someone interested in studying evolutionary anthropology?
JT: I would encourage them to take as many courses as they can. Anthropology is a huge field and the subfield of evolutionary anthropology is also diverse, with specializations in nonhuman primate behavioral ecology, paleoprimatology, paleoanthropology, human biology and health, molecular anthropology, forensic anthropology, archaeology, and bioarchaeology. Exposure to all of these specializations will help students make the best choice for where they would like to focus their studies.