Agonism, Affiliation, and Social Organization in a Community of Savanna Chimpanzees (Pan troglodytes verus) at Fongoli, Senegal

This dissertation illuminates the structure of social life in a community of savanna chimpanzees at Fongoli, Senegal. Where this study differs from some others is that in addition to conspicuous and active acts of affiliation and aggression, subtler social phenomena were also recorded. The commonness, context, and intensity of these various behaviors are described in detail and compared to other study sites when data are available. The first part of the dissertation sets up a theoretical and methodological framework for the study of patterns of social behavior in chimpanzees. Chapter 1 provides a summary of the use of chimpanzees as proxies for humans and theories explaining lethal aggression in these two species. Chapter 2 describes the particulars of the Fongoli study site and community, as well as basic data collection methods. In Chapter 3, conceptions of aggression, social hierarchy, and conflict are discussedin particular, differentiating aggression directly tied to hierarchy in a narrow sense from that tied to it only broadly. In Chapter 4, methods of data collection and analysis are explained with regard to contact aggression specifically. The second part of the dissertation covers data analysis and interpretation. In Chapter 5, patterns of contact aggression at Fongoli are described and compared to published data from other sites. In Chapter 6, patterns of the basic activity budget and social behavior other than contact aggression and copulation are examined. In Chapter 7, copulation patterns are discussed. In Chapter 8, results are summarized and discussed in connection with broad theoretical concerns such as the social bauplan, affect hunger, the concept of competition, social hierarchy as right-of-way, organizational change as rites of passage, an alternative to lethal aggression as adaptive behavioral trait, and how dynamic social systems are structured and change. Summarizing patterns of social behavior at Fongoli, affiliation rather than aggression was an all-consuming aspect of chimpanzee life. Aggression was rare and, like high dominance rank, was not associated with copulation success. Therefore, dominance-submission roles served as a sort of right-of-waya way to avoid deleterious conflict which benefited all membersnot just those of high rank. Also, dominance in one sphere did not necessarily carry over into others. Aggression with physical contact was particularly rare, was generally of low intensity, and seemed most proximately tied to spatial friction rather than to attempts to monopolize resources, i.e., competition. In each of the few instances of severe intensity contact aggression, it was associated with potential restructuring of the male dominance hierarchy, such as in changes in alpha status and the transition from adolescence into adulthood. It appears that as role certainty or familiarity decreases, the intensity of aggression increases. Further, separate adaptive explanations for lethal aggression (not observed during this study) within communities during periods of particular social instability, or towards individuals from other communities or those living peripherally, are not required. The difference between severe and lethal aggression is likely one not of kind, but of degree

<Note> Savanna Chimpanzees (Pan troglodytes verus) Prey on Patas Monkeys (Erythrocebus patas) at Fongoli, Senegal

Chimpanzees across Africa include some meat in their diet1. In most communities where chimpanzees have been studied over the long term, primate prey is apparently preferred over other animal prey, with red colobus monkeys (Piliocolobus badius) comprising the most common monkey species eaten2. At Fongoli, Senegal, it is likely that chimpanzees have never had access to red colobus monkeys at this hot, dry and open site, although the range of red colobus monkeys (P.b. temminckii) in Senegal and adjacent countries in West Africa has diminished3. Fongoli chimpanzees are currently not sympatric with red colobus, although they eat vertebrate prey of various types, including a number of primate species

Savanna Chimpanzees (Pan troglodytes verus) Prey on Patas Monkeys (Erythrocebus patas) at Fongoli, Senegal

Chimpanzees across Africa include some meat in their diet1. In most communities where chimpanzees have been studied over the long term, primate prey is apparently preferred over other animal prey, with red colobus monkeys (Piliocolobus badius) comprising the most common monkey species eaten2. At Fongoli, Senegal, it is likely that chimpanzees have never had access to red colobus monkeys at this hot, dry and open site, although the range of red colobus monkeys (P.b. temminckii) in Senegal and adjacent countries in West Africa has diminished3. Fongoli chimpanzees are currently not sympatric with red colobus, although they eat vertebrate prey of various types, including a number of primate species.This is an article from PAN Africa News 16 (2009): 15. Posted with permission.</p

Intragroup Lethal Aggression in West African Chimpanzees (Pan troglodytes verus): Inferred Killing of a Former Alpha Male at Fongoli, Senegal

© 2017, Springer Science+Business Media New York. Lethal coalitionary aggression is of significant interest to primatologists and anthropologists given its pervasiveness in human, but not nonhuman, animal societies. Chimpanzees (Pan troglodytes) provide the largest sample of recorded lethal coalitionary aggression in nonhuman primates, and most long-term chimpanzee study sites have recorded coalitionary killing of conspecifics. We report an inferred lethal attack by resident males on a former alpha male chimpanzee (P. t. verus) at Fongoli in Senegal. We describe the male’s presence in the community, his overthrow, social peripheralization for \u3e 5 yr, and his attempt to rejoin the group as well as circumstances surrounding his death. We report attacks by multiple chimpanzees on his dead body, most frequently by a young adult male and an older female. The latter also cannibalized the body. Coalitionary killing is rare among West African chimpanzees compared to the East African chimpanzee (P. t. schweinfurthii). This pattern may relate to differences in population densities, research effort, and subspecies differences in biology and behavior

Update on the Assirik Chimpanzee (Pan troglodytes verus) Population in Niokolo Koba National Park, Senegal

The Assirik, Senegal chimpanzee population was studied extensively by McGrew and colleagues in the Stirling African Primate Project (SAPP) in the late 1970s1 and surveyed by the Miami Assirik Pan Project (MAPP) in 20002. These chimpanzees (thought to represent a single community3), within the Niokolo Koba National Park (or Parc National du Niokolo Koba, PNNK), remain the only protected population in the country, with most of Senegal’s chimpanzees living in unprotected areas4. In 2012, the Iowa State Assirik Primate Project (ISAPP) surveyed Assirik and outlying areas in the PNNK to assess chimpanzee density and to explore the possibility of establishing a research program there in collaboration with the National Parks Department of Senegal and University of Cheikh Anta Diop in Dakar. One objective in this study was to resurvey the Assirik area in order to compare our results to data collected in 2000.This is an article from PAN Africa News 19 (2012): 8. Posted with permission.</p

Intragroup Lethal Aggression in West African Chimpanzees (Pan troglodytes verus): Inferred Killing of a Former Alpha Male at Fongoli, Senegal

Lethal coalitionary aggression is of significant interest to primatologists and anthropologists given its pervasiveness in human, but not nonhuman, animal societies. Chimpanzees (Pan troglodytes) provide the largest sample of recorded lethal coalitionary aggression in nonhuman primates, and most long-term chimpanzee study sites have recorded coalitionary killing of conspecifics. We report an inferred lethal attack by resident males on a former alpha male chimpanzee (P. t. verus) at Fongoli in Senegal. We describe the male’s presence in the community, his overthrow, social peripheralization for \u3e 5 yr, and his attempt to rejoin the group as well as circumstances surrounding his death. We report attacks by multiple chimpanzees on his dead body, most frequently by a young adult male and an older female. The latter also cannibalized the body. Coalitionary killing is rare among West African chimpanzees compared to the East African chimpanzee (P. t. schweinfurthii). This pattern may relate to differences in population densities, research effort, and subspecies differences in biology and behavior