Infectious Diseases in Primates: Behavior, Ecology and Evolution

Transcription

1 Oxford Scholarship Online You are looking at 1-10 of 10 items for: keywords : Philippines biodis bioani Infectious Diseases in Primates: Behavior, Ecology and Evolution Charles Nunn and Sonia Altizer Item type: book acprof:oso/ Recent progress in the field of wildlife disease ecology demonstrates that infectious disease plays a crucial role in the lives of wild animals. Parasites and pathogens should be especially important for social animals in which high contact among individuals increases the potential for disease spread. As one of the best studied mammalian groups, primates offer a unique opportunity to examine how complex behaviours (including social organization) influence the risk of acquiring infectious diseases, and the defences used by animals to avoid infection. This book explores the correlates of disease risk in primates, including not only social and mating behaviour but also diet, habitat use, life history, geography and phylogeny. The authors examine how a core set of host and parasite traits influence patterns of parasitism at three levels of biological organization: among individuals, among populations, and across species. A major goal is to synthesize, for the first time, four disparate areas of research: primate behavioural ecology, parasite biology, wildlife epidemiology, and the behavioural and immune defences employed by animals to counter infectious disease. Throughout, the authors provide an overview of the remarkable diversity of infectious agents found in wild primate populations. Additional chapters consider how knowledge of infectious diseases in wild primates can inform efforts focused on primate conservation and human health. More generally, this book identifies infectious disease as an important frontier in our understanding of primate behaviour and ecology. It highlights future challenges for testing the links between host and parasite traits, including hypotheses for the effects of disease on primate social and mating systems. Page 1 of 6

2 Questions, terminology, and underlying principles acprof:oso/ This chapter begins by laying out the purpose of this book, which is to examine the links between parasitism and primate behaviour, ecology and evolution. A question central to this book is what factors influence disease risk? In other words, what intrinsic host characteristics and environmental parameters determine the number and types of parasites infecting wild animals at the individual, population, and species levels? A second and related question is how can animals reduce this risk? The book also explores the implications of infectious disease in nonhuman primates for both public health and conservation concerns. Definitions are provided for the terms parasite, disease, and disease risk. The ecological drivers or primate sociality and fitness consequences of parasites in wild primate populations are discussed. An overview of the subsequent chapters is presented. Diversity and characteristics of primate parasites acprof:oso/ This chapter reviews the biological features of major groups of parasites and links these features to specific aspects of disease risk in primates. It identifies the parasite characteristics that are most important to understanding patterns of disease risk, including transmission strategy, host specificity, parasite life cycles, virulence, and how parasites manipulate host behaviour in order to enhance their transmission. Page 2 of 6

3 Primate socioecology and disease risk: predictions and rationale acprof:oso/ This chapter discusses the underlying rationale for factors that influence disease risk in primates at two levels: among individuals and across species. Throughout it summarizes primate behavioural and ecological traits that are essential for understanding disease risk, including: dominance rank; group size and composition; dispersal; mating system; and ecological factors that correlate with these social system parameters, such as body mass, life history characters, and use of the ground versus trees for locomotion (substrate use). Host parasite dynamics and epidemiological principles acprof:oso/ This chapter links host and parasite ecology by considering basic epidemiological parameters and processes, and it covers how disease patterns scale up from individuals to populations and communities. It discusses factors affecting the transmission dynamics of parasites, including the basic reproductive number R0, the aggregation of macroparasites within populations, and frequency- versus densitydependent transmission. This chapter also considers how parasites might regulate primate populations or influence host abundance through their effects on survival and fecundity. Host defenses: the immune system and behavioral counterstrategies Page 3 of 6

4 acprof:oso/ This chapter examines the host's response to parasitism by considering behavioural and immunological defences to infectious disease. It focuses on the individual level by considering how primate immune systems defend against parasite infections, how animals use medicinal plants, and the avoidance of sick individuals. It also investigates the links between sexual selection and parasitism in primates, focusing in particular on mate choice. Infectious disease and primate social systems acprof:oso/ This chapter integrates material from the previous chapters in order to explore the ways in which parasites might influence primate mating and social systems. It considers how individual responses to parasitism can influence social-system characteristics, and raises the question of causality, namely, do host traits influence patterns of parasitism, or do parasites influence patterns of sociality? These are not mutually exclusive questions, but by considering a coevolutionary model of host and parasite traits, the multiple ways in which lineages of hosts and parasites interact can be addressed. Parasites and primate conservation acprof:oso/ This chapter investigates the role of infectious diseases in primate conservation. It focuses on two issues central to the conservation of primates: anthropogenic effects on disease risk in wild populations, including the emergence of new diseases, and the importance of considering parasites when planning conservation efforts. It begins by considering the direct effects of parasites on host population declines, focusing on emerging infectious diseases (EIDs) and impacts of humans Page 4 of 6

5 on disease risk in wildlife. It then discusses how conservation efforts can become more effective by taking into account risks from infectious disease. Given the numerous examples of pathogen-driven wildlife declines, a need exists for wildlife managers to quantify parasite occurrence in primates to obtain baseline knowledge on the parasites that are present, to gain an understanding of transmission modes and impacts on individual hosts, and to identify potential reservoirs of infection in other hosts that might cross-infect primates. The last section shifts gears by considering the potential role of parasites in promoting biodiversity. From nonhuman primates to human health and evolution acprof:oso/ This chapter considers how understanding infectious disease in nonhuman primates provides insights to human health. In particular, it examines the origins of human infectious diseases and their impacts in a historical context. More speculatively, it asks how behavioural counterstrategies to infectious disease in nonhuman primates pertain to understanding human behaviour in the context of Darwinian medicine. It also discusses the role of wild primates in the maintenance of zoonotic pathogen and disease emergence, and applies the concept of disease risk in order to investigate variation in human infections at global and regional scales. Concluding remarks and future directions acprof:oso/ This chapter reviews key points in the book and identifies areas for future research, pointing to future challenges for testing the links between host and parasite traits in wild primate systems. Topics covered include the diversity of parasites in wild primates, population biology and impacts of parasites in wild primates, immune and behavioural defences, the Page 5 of 6

6 links between primate sociality and parasitism, and whether parasites are a significant threat to primate conservation efforts. It also discusses how knowledge of infectious disease in nonhuman primates can provide insights to human health at both basic and applied levels. Page 6 of 6