Suzanne Ripley suffered an aortic dissection and died at the age of 72 on February 22, 2008, in Los Angeles, California. She was spending a few months away from her home in Edgecomb, Maine, and planning, according to her journal, “the next quarter century of my life.” Sue was one of the early group of anthropology graduate students of Sherry (Sherwood) Washburn who conducted field studies of nonhuman primates in the 1960s. Each collected baseline data on the social organization and ecology of a ground-dwelling primate species as part of Washburn's call for a “new physical anthropology” in which field studies of nonhuman primate behavior provide a key element for understanding the evolution and behavior of humans. Sue Ripley developed a field site in Polonnaruwa in Sri Lanka and her work there on Ceylonese grey langurs formed the basis of much of her later work. She had actually started graduate study in cultural anthropology at UC Berkeley but switched to physical anthropology in her first year. Sue felt equally comfortable on both sides of the human-nonhuman primate continuum. Early in her career, because of her interest in human communication, she was invited to participate in the 1970 Wenner Gren Conference on Interaction Ethology organized by Erving Goffmen and Thomas Sebeok, and in 1965, she worked for a year with Raymond Birdwhistell, the founder of the study of human kinesics, at the Eastern Pennsylvania Psychiatric Institute. Sue earned a PhD in Anthropology from the University of California, Berkeley in 1965. She was a member of the department of anthropology at City College of New York in the early 1970s, and later taught for one year in 1981 as a visiting professor at UCLA.
Sue's primary focus was always the intersection of evolution, ecology and behavior. Probably her most important piece of work was her 1967 paper published in the American Journal of Physical Anthropology titled “Leaping of langurs: a problem in the study of locomotor adaptations.” In it, she took on the established categories of locomotor patterns in primates in which species were labeled by particular locomotor types, for example, quadruped or brachiator. Sue pointed out that there are several factors besides anatomy involved in how a species moves. She argued that the anatomy of a species evolved through its interaction with a specific configuration of environmental features—trees with particular branch patterns with limbs of particular sizes, to name just one. To understand how and why a species of primate moves as it does and has the anatomy it does, one must get out of the laboratory and watch it move in its natural habitat. Furthermore, the object of study must be a whole group of animals, since anatomy is shaped by natural selection over a reproductive lifespan and individuals of different ages engage the environment differently. Habitats must be described in extremely specific ways so that anatomical features can be seen as the result of movement and postures that interact with the complex environment in which the animals live. In this paper, Sue suggested elements of movement, posture and habitat type that must be defined in order to truly understand the anatomy of a primate species, and hence, its evolution. John Fleagle, Professor of Anthropology at the State University of New York at Stony Brook, says of this paper: “it was one of the most important papers in the history of primatology… (it) inspired a whole generation of researchers and was the impetus behind many careers” (his included). Sue went on to write other papers refining and using her paradigm, expanding it to include ways of studying and understanding feeding behavior as an evolved part of a species' biology. Her last paper was a comparison of infanticide in langur monkeys and humans, arguing that since both species are successful generalists and share a fundamental adaptation to drier seasonal habitats, a comparison of their use of infanticide to limit population could be illuminating.
In 1967, she and Smithsonian biologist John Eisenberg were awarded a Currency Project grant for a multi-year, multidisciplinary project studying primates and elephants at Polonnaruwa, in Sri Lanka. Over the years, this project has included many scientists and graduate students, and Sue was especially proud of the number of Sri Lankan students and field workers who were trained at that site.
In the months since Sue's death, I have been in touch with many colleagues who knew her. I was surprised to learn how widespread her circle was and how much she was admired for her contributions to the field. Dr. Sarah Hrdy, noted anthropologist and fellow langur researcher, wrote: “In terms of the work … (Sue) did in the early years, she was among the very best… As well as a fieldworker, she was a scholar's scholar intent on charting new paths, and also someone determined to find a precise terminology to interpret her ideas. I still smile when I think of Sue's phrase “monopodal arboterrestrial link”. It was her term for a tree, and from the perspective of the ecology, locomotion and behavior of a monkey, that's exactly what a tree is.”
Sri Lankan primatologist, Rudy Rudran wrote: “Sue was a modern day pioneer of Primatology in Sri Lanka. She was instrumental in launching the Sri Lanka Primate Project way back in the early 1960s which continues even today with the work of Wolfgang Dittus. And just last year I renewed my work on Sri Lanka's endemic purple-faced langur—I likely would not have re-started this project had I not been part of the team that Sue set up for the Smithsonian Institution at Polonnaruwa. As a young Sri Lankan graduate working on the Smithsonian Project as a Field Assistant, Sue was the first person who introduced me to field research on primates, which was practically unheard of in those days in Sri Lanka. I learnt a great deal from her about the work ethic and the commitment that was required to follow monkeys from dawn to dusk to study their ecology and behavior. This lesson has stayed with me right through my career as a Primatologist during the past forty years, and I am the richer for it. There were many other Sri Lankans who also benefited from Sue's counsel and enthusiasm for primate field investigations. So it is with great sadness that I received the news that Sue is no more. May she rest in peace.”
Colleagues all included the words “pioneer” when they spoke of Sue—yes, Sue was out there, and she blazed trails for many of us. She was challenging, exhausting, and always pushing the boundaries. She leaves anthropology a legacy that includes a number of published papers all of which expand our thinking in major new directions, a field site in Sri Lanka that has contributed to our understanding of primate and human evolution for more than 40 years, and for those of us who knew her, a more rigorous and adventurous way to think about the research issues that we are working on.