Karin Enstam Jaffe, Ph.D., Sonoma State University
- Describe the behavioral variation that exists within the Primate Order and how primate behavior and morphology are influenced by diet, predation, and other ecological factors.
- Explain why primates live in groups.
- Distinguish primate social systems from mating systems.
- Contrast male and female reproductive and parental investment strategies.
- Describe the ways in which primates communicate.
- Evaluate the evidence for primate cultural variation.
Nonhuman primates (from now on simply referred to as “primates”) are our closest living relatives, and their behavior is often strikingly similar to our own. If you’ve ever seen a female monkey at your local zoo cooing over her newborn baby (Figure 6.1a) or watched a video of a tufted capuchin monkey using rocks as a hammer and anvil to crack open a nut to access the edible kernel inside (Figure 6.1b), then you know how interesting they can be.
I have been fascinated by primates since I was a young child. In the summer of 1996, I went with my dissertation advisor, Dr. Lynne A. Isbell, to her field site in Laikipia, Kenya (Figure 6.2) with the intention of studying the play behavior of juvenile patas monkeys. One day we were following our patas study group when several females and juveniles began giving high-pitched “nyow” alarm calls. I was awestruck as I watched the entire group take off at breakneck speed. Patas monkeys are, after all, the fastest primate, capable of running 20 miles per hour for short distances. It did not even occur to me that they had sounded an alarm and then run away from something —until my advisor pointed to the lioness hidden in the grass at the base of a tree. (We slowly backed away and got in our car.) My research interests changed in that moment: I wanted to study primate antipredator behavior, the strategies primates use to escape from predators. I would spend two years at that same field site collecting data on anti-predator behavior of patas monkeys and vervets, two closely related species who occupy different habitats. Patas monkeys (Figure 6.3a) live far from rivers, in habitats composed of short trees spaced far apart (Figure 6.3b). These trees have little to no overlapping canopy, so climbing one to escape a lion in pursuit can result in a literal dead end. In contrast, vervets (Figure 6.4a) spend most of their time along rivers, with access to tall trees with overlapping canopies (Figure 6.4b) that provide good escape routes from terrestrial predators. But they also venture into patas habitats, the short trees with canopies that do not overlap. I wanted to know: How would the structure of these habitats affect the responses of vervets and patas monkeys to alarm calls that signal the approach of a terrestrial predator like a lion? Not surprisingly, when vervets are near the river, they climb the tall trees to seek refuge from such predators. But not patas monkeys. These “cheetahs of the primate world” are more likely to take off running (as I had seen them do that summer), even bypassing nearby trees. Their physical adaptations for speed, like their long legs, combined with the lack of arboreal escape routes, makes fleeing on the ground their best option. But what do vervets do when they are away from the river and the safety of their tall trees? Is their behavior “hard-wired” so that their response to an alarm call is the same, regardless of the habitat? Or do they assess key aspects of their habitat, like tree height and canopy cover, and alter their behavior? Although they cannot run as fast, when they hear an alarm call they run back toward the river, by-passing the short trees, just like the patas do (Enstam and Isbell 2002). The implication is clear: these monkeys, our close relatives, with their highly developed intelligence and ability to learn, do assess key features of their habitat and use this information to alter their behavior and maximize their chance of escape.
The branch of science that focuses on the study of primate behavior is called primatology, and people, like myself, who study primates (Figure 6.5) are called primatologists. Primatologists come from many different disciplines and study primate behavior for different reasons. Biologists study primates as examples of evolutionary theories like natural selection or parental investment. Primate intelligence is of interest to psychologists who want to learn more about the underlying cognitive principles involved in deceptive or cooperative behavior and to linguists interested in the principles of communication and language. Ecologists studying conservation issues examine how primates are affected by deforestation, poaching, or illegal animal trade. Biological anthropologists, like myself, who study primates are interested in their social complexity and ecological and behavioral variation. Because both humans and most nonhuman primates live in groups, biological anthropologists study primates to better understand the evolution of social behavior and its costs and benefits. Because primates are our closest living relatives, we study them to gain insights into how our human ancestors may have behaved as well as to better understand our own behavior.
About the Author
Karin Enstam Jaffe
Sonoma State University, email@example.com
Dr. Karin Enstam Jaffe has loved primates since she was five years old. As an undergraduate at U.C. San Diego, she participated in projects studying orangutans, langurs, and Mona monkeys. She earned her Ph.D. in Anthropology from U.C. Davis studying vervet and patas monkey anti-predator behavior. Dr. Jaffe has over 20 years of experience studying primate behavior in Kenya and Grenada and at the San Diego Zoo, San Francisco Zoo, and Safari West Wildlife Preserve in Sonoma County, California. She has been a faculty member in the Anthropology Department at Sonoma State University since August 2002. A dedicated teacher-scholar, Dr. Jaffe has won several teaching, scholarship, and mentoring awards, including SSU’s Excellence in Teaching Award, Educational Experience Enhancement Award, and the President’s Excellence in Scholarship Award. In addition to teaching, she is a Research Associate at Oakland Zoo, where she has been involved in behavioral enrichment research involving ring-tailed lemurs, chimpanzees, and sun bears, as well as a study of the social network of hamadryas baboons.
For Further Exploration
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Primate Info Net (http://pin.primate.wisc.edu/) is an information service of the National Primate Research Center at the University of Wisconsin, Madison. It includes Primate Factsheets, primate news and publications, a list of primate-related jobs, and an international directory of primatology, among other information.
Primate Specialist Group (http://www.primate-sg.org/) is a collection of scientists and conservationists who work in dozens of African, Asian, and Latin American nations to promote research on primate conservation.
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The author is grateful to the editors for the opportunity to contribute to this open-source textbook. She thanks Stephanie Etting for her encouragement and support during the writing of this chapter. Her suggestions, along with comments made by two anonymous reviewers on an earlier version of this chapter, improved the final version considerably. Finally, she thanks all the primatologists who came before her, especially her advisor, Lynne A. Isbell, for their tireless efforts to understand the behavior and ecology of the living primates. Without their work, this chapter would not have been possible.
Figure 6.1a Snow monkey baby milk time by Daisuke tashiro is used under a CC BY-SA 2.0 License.
Figure 6.1b Stone tool use by a capuchin monkey by Tiago Falótico is used under a CC BY-SA 4.0 License.
Figure 6.2 Laikipia location map by Nairobi123 is used under a CC BY-SA 3.0 License.
Figure 6.3a Female patas monkey with infant by Karin Enstam Jaffe is under a CC BY-NC 4.0 License.
Figure 6.3b Patas habitat in Laikipia, Kenya by Karin Enstam Jaffe is under a CC BY-NC 4.0 License.
Figure 6.4b Vervet habitat in Laikipia, Kenya by Karin Enstam Jaffe is under a CC BY-NC 4.0 License.
Figure 6.5 Karin Enstam Jaffe observing patas monkeys in Laikipia, Kenya by Rebecca Chancellor is under a CC BY-NC 4.0 License.
Figure 6.6a Spectral Tarsier Tarsius tarsier (7911549768) by Bernard DUPONT from FRANCE has been modified (cropped) and is used under a CC BY-SA 2.0 License.
Figure 6.7 Food abundance and food scarcity by Karin Enstam Jaffe original to Explorations: An Open Invitation to Biological Anthropology is under a CC BY-NC 4.0 License.
Figure 6.8 Food distribution patterns by Karin Enstam Jaffe original to Explorations: An Open Invitation to Biological Anthropology is under a CC BY-NC 4.0 License.
Figure 6.9 Food distribution patterns of folivores, frugivores, and insectivores a derivative work by Karin Enstam Jaffe original to Explorations: An Open Invitation to Biological Anthropology is under a CC BY-NC 4.0 License. [Includes Green fruit tree, Lemon tree, and Ladybug image, all from publicdomainvectors.org designated to the public domain (CC0)].
Figure 6.10 Termite mound-Tanzania by Vierka Maráková, Slovakia (Krokodild) has been designated to the public domain (CC0).
Figure 6.11b Chlorocebus pygerythrus by Xlandfair at English Wikipedia has been designated to the public domain (CC0).
Figure 6.11d Komba ušatá2 by Petr Hamerník is used under a CC BY-SA 4.0 License.
Figure 6.12 Muriquis 3 by Mônica Imbuzeiro is used under a CC BY-SA 4.0 License.
Figure 6.13 Examples of primate communities table original to Explorations: An Open Invitation to Biological Anthropology by Karin Enstam Jaffe is under a CC BY-NC 4.0 License.
Figure 6.14a Lion tailed macaque eating Lizard by Prasadchangarath is used under a CC BY-SA 4.0 License.
Figure 6.14b Gombe Stream NP Beute by Ikiwaner is used under a GNU License.
Figure 6.15a Leopard africa by JanErkamp at the English Wikipedia is used under a CC BY-SA 3.0 License.
Figure 6.15d Fosa fotovideo by Bertal is used under a CC BY-SA 3.0 License.
Figure 6.15f Harpy Eagle with wings lifted by Jonathan Wilkins is used under a CC BY-SA 3.0 License.
Figure 6.15g Python natalensis G. J. Alexander by Graham J. Alexander, University of the Witwatersrand has been designated to the public domain (CC0).
Figure 6.16 Slow Loris by Jmiksanek is used under a CC BY-SA 3.0 License.
Figure 6.17 Monkey group by Natureloverperson is used under a CC BY-SA 4.0 License.
Figure 6.18b Lemur poaching 004 by author who does not wish to be named for safety reasons is used under a CC BY-SA 3.0 License.
Figure 6.22 Social and Mating Systems by Karin Enstam Jaffe original to Explorations: An Open Invitation to Biological Anthropology is under a CC BY-NC 4.0 License.
Figure 6.23a Jane Goodall HK by Jeekc is used under a CC BY-SA 3.0 License.
Figure 6.23c Dr Birute Galdikas by Simon Fraser University – University Communications is used under a CC BY 2.0 License.
Figure 6.24b Hamadryas baboon at Giza Zoo by Hatem Moushir 36 by Hatem Moushir is used under a CC BY-SA 3.0 License.
Figure 6.25 Mandrill 08 by SuperJew is used under a CC BY-SA 4.0 License.
Figure 6.26 BabouinGeladaAuReveil by BluesyPete is used under a CC BY-SA 3.0 License.
Figure 6.27 Mandrill 09 by SuperJew is used under a CC BY-SA 4.0 License.
Figure 6.28a Uakari by Coada dragos is used under a CC BY-SA 4.0 License.
Figure 6.29 Lemur catta 004 by Alex Dunkel (Visionholder) is used under a CC BY-SA 3.0 License.
Figure 6.30a Yakushima macaques grooming each other by Grendelkhan is used under a CC BY-SA 4.0 License.
Figure 6.30b Tufted capuchin monkeys grooming session III by Adrian Soldati is used under a CC BY-SA 4.0 License.
Figure 6.30c Baboons Wunania 012018 by Kim Toogood is used under a CC BY-SA 4.0 License.
Figure 6.30d Black-and-white ruffed lemur 03 by Mattis2412 has been designated to the public domain (CC0 1.0).
Figure 6.31 Pan troglodytes, tool use in Senegal by J. D. Pruetz, P. Bertolani, K. Boyer Ontl, S. Lindshield, M. Shelley, and E. G. Wessling is used under a CC BY 4.0 License.
Figure 6.32 Jigokudani hotspring in Nagano Japan 001 by Yosemite is used under a CC BY-SA 3.0 License.
- Smithsonian Channel. June 9, 2017. “Why These Vegetarian Monkeys Have Sharp Predator Teeth.” Accessed July 25, 2019. https://www.youtube.com/watch?time_continue=145&v=aC6iYj_EBjY↵
- National Geographic. n.d. “Chimps and Tools.” Accessed July 25, 2019. https://video.nationalgeographic.com/video/00000144-0a1e-d3cb-a96c-7b1fadbd0000↵
- National Geographic. n.d. “Meditative Snow Monkeys Hang Out in Hot Springs.” Accessed July 25, 2019. https://video.nationalgeographic.com/video/short-film-showcase/00000149-d415-de71-a9eb-dc9539210000↵