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Symbiotic associations between plants and fungi are very common in ecological communities. In grasses, the hyphae of endophytic fungi (Family Clavicipitaceae; Tribe Balansiae) can be found growing between the cells of stems, leaves, and seeds. In terms of the endophyte's effect on the host, extensive investigation has revealed that the symbioses can range from parasitism to commensalism to mutualism. Effects of the endophyte on host grasses depends greatly on environmental conditions and the genotype of host and endophyte. The ramifications of endophyte-infected grasses within natural communities are complex and involve interactions among host plants, and primary and secondary consumers. Agronomically important grasses such as Festuca and Lolium species have been the most widely studied grass-endophyte systems. The assessment of endophyte infections in host populations using histochemical, biochemical, and molecular techniques reveals that the frequency of infection varies among populations, individuals, and tillers within individuals. The relative level or intensity of infection can also vary within and among tillers, and among individual host plants within a population. Grass-endophyte symbioses have the potential to impact their associated animal and plant communities as well as the ecosystems in which they occur.

Three natural quasi-asexual or quasi-sexual genetic modes (hybridogenesis, hybridogenesis, and kleptogenesis) can be described as parthenogenetic-like processes with added dashes of sex. Females in the clonal or hemi-clonal taxa that live these reproductive lifestyles are not virgins; rather, each mates with a male from a foreign species and utilizes his sperm. However, because of the cellular mechanics involved, these males usually make no lasting genetic contribution to future generations of the unisexual lineage. Instead, they have been the duped victims of sexual parasitism. Approximately 50 “species” of fish and amphibian, usually but not always consisting solely of females, constitutively reproduce by one or another of these mechanisms of sexual parasitism. This chapter describes the cellular bases, evolutionary histories, and ecological ramifications of all known cases of sperm-dependent unisexuality in vertebrate animals.

The diversity in size, shape, and growth requirements of different plants produces an astonishing array of features to see — from hairs, thorns, and waxes to tilting responses towards sunlight (phototaxis) and rapid responses to touch (sensitive plants). Widely differing growth forms also occur, including life styles associated with photosynthesis, parasitism, and carnivory, as well as the mining and galling effects of insects. This chapter describes a few of the many intriguing features of plants, including descriptions of the above characteristics as well as lenticels, plant patches, variegated leaves, and poison plants.

Community ecology and ecosystem ecology provide different perspectives on ecological systems, and have followed increasingly divergent pathways for decades. Recent theoretical and experimental work has begun to integrate these perspectives and provides new light on how species and ecosystems are mutually interdependent. A number of experiments and models have shown that species diversity affects ecosystem functioning through either selection of appropriate dominant species or complementarity among species with different traits. Although particular species may have a large functional impact only at small scales, some hypotheses and experimental evidence suggest that species diversity may also be critical at large temporal and spatial scales. These conclusions, however, have been obtained in relatively simple systems. A major future challenge is to extend this knowledge to full ecosystems with multiple trophic levels and multiple processes, and to determine how biodiversity dynamics, ecosystem processes, and abiotic factors interact.

This chapter explores Portuguese colonial relations with Timorese marriage institutions during the late colonial period. By drawing on the rich colonial history of the barlake (traditional marriage contracts) in East Timor, it proposes a novel approach to the trope of intermarriage in the Portuguese-speaking world. In addressing the variety of relationships with marriage in colonial practice, the chapter conceptualises three main types of colonial interactions with indigenous marriage: predatory, parasitic and mimetic. It uses case studies to show how these distinct forms of interaction could be associated with distinct colonial agents and their particular agendas. The chapter shows how, in late nineteenth-century East Timor, colonial relationships with barlake were marked by a tense coexistence between, on the one hand, the predatory model followed by the Catholic missionaries, and, on the other hand, the parasitic exploitation of indigenous marriage ties, customarily practised by colonial officers and governors.

This chapter deals with a number of topics not related to particular organ systems, but to the general body organization. These include: complexity (is there a constantly growing complexity during animal evolution?), size (can events of evolutionary size change be spotted?), symmetry (what are the basic symmetrical properties and what is their phylogenetic importance?), the anteroposterior axis (what is its significance for bilaterian evolution and did it predate Bilateria?), the dorsoventral axis (was there an inversion of this axis during metazoan evolution?), germ layers (what is the phylogenetic significance of germ layers?), segmentation (how often did segmentation and segmental patterns evolve?), skeletons (are skeletons phylogenetically informative?), locomotory appendages (are appendages comparable among animals?), and parasitism (what are the evolutionary changes in becoming parasitic?).

This chapter considers patterns of evolution in exotic bird populations. Evidence is presented that exotic birds have evolved in their phenotypes over the relatively short time spans in which they have been established in their new locations. Some of the shifts observed are entirely consistent with macroevolutionary patterns observed amongst native bird species; others are more curious and require reconsideration of some long-held views of evolutionary dynamics. The chapter notes the great potential for research on the evolution of exotic birds to provide insight into basic evolutionary theory and the role of evolution in the impacts of all invasive species.

This chapter starts by examining a simple classification of interaction between just two species into +, 0, or -. This produces a 3x3 matrix which reduces to six possible interactions. Only three have been studied by ecologists in any detail. These three are the following; (+ -) interactions: this covers grazing, browsing, and parasitism as well as traditional predator-prey interactions. The question is asked, are these savannah systems top-down or bottom-up regulated? To what extent are interactions important in the migration of ungulates? This chapter also examines the idea of multiple stable states and cycles, using the ‘fire, elephants, and trees’ interaction; (- -) interactions: usually called interspecific competition. Do the herbivores compete for resources? How important is kleptoparasitism between the major carnivores and is it responsible for the demise of such species as wild dogs in some areas? What is the evidence for resource partitioning?; (+ +) interaction: traditionally called mutualism. The ant-acacia interaction and the browsing ungulates. Is the so-called grazing succession real? Vultures, carnivores and carrion. How important are these mutualisms in the dynamics of the savannah systems?

This chapter begins with a description of the case of Mr. Pickles, who in 1895 was allowed by the Judges of the House of Lords to get away with a vicious trick he had played on the community of Bradford, England. The year before, Pickles had deliberately diverted the course of a stream that was flowing through his land so that it no longer supplied the municipal water reservoir. The main arguments of the book are then presented. This is followed by an overview of the subsequent chapters.

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.

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.

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 density-dependent transmission. This chapter also considers how parasites might regulate primate populations or influence host abundance through their effects on survival and fecundity.

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.

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.

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 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.

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 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.

Predators aren't the only exploiters of bison. Like all big organisms they are a resource for hundreds of kinds of tiny life forms that use them in a variety of intriguing ways. And size is no protection at all from very small things; it just makes them a bigger target. Many bison in Yellowstone Park have brucellosis, and it is possible that those bison could transmit the disease to cattle if they occupied the same range at the same time. Most diseases go easy on their host, but anthrax, which arrived in North America from Europe around 1800, is a killer.Bacillus anthracis destroys the bison in a kind of slow explosion, and uses the energy to propel its spores into a search for a new set of lungs. Meanwhile, the winter tick quests for most of North America's large mammals, including bison.

Host–pathogen associations continue to generate some of the most important applied problems in population biology. In addition, as foreshadowed in Chapter 5 of this volume, these systems give important insights into the dynamics of host– natural enemy interactions in general. The special place of pathogens in the study of host–natural enemy dynamics arises partly from excellent longterm disease-incidence data, reflecting the public health importance of many infections. However, we argue that host–pathogen dynamics are also distinctive because the intimate association between individual hosts and their pathogens is often reflected with particular clarity in the associated population dynamics. Throughout this chapter we focus in parallel on the population dynamics of host–pathogen interactions and the insights that host–pathogen dynamics can provide for population biology in general. Population-dynamic studies of infectious disease have a long history, which predates the modern foundations of ecology (Bernoulli, 1760). During the twentieth century, the preoccupation of population ecologists with the balance between extrinsic and intrinsic influences on population fluctuations and the role of nonlinearity and heterogeneity (Bjørnstad and Grenfell, 2001) find strong parallels in epidemiological studies of human diseases (Bartlett, 1956; Anderson and May, 1991). In terms of the ecological effects of parasitism, the traditional view held that ‘welladapted’ parasites would not have a consistent impact on the ecology of their hosts (Grenfell and Dobson, 1995). The 1970s saw a new departure, when Anderson and May pointed out the potential of infectious agents to exert nonlinear—regulatory or destabilizing—influences on the population dynamics of their hosts (Anderson and May, 1978, 1979; May and Anderson, 1978, 1979). There has since been an explosion of work on the population biology of human, animal, and plant pathogens. This work spans a huge range: from highly applied to basic theoretical work; from within-host to the metapopulation scale; from short-term population dynamics to long-term evolutionary processes. In this chapter we first outline the simple theory of epidemiological models; we then refine this picture to illustrate the potential impact of pathogens on the population dynamics of their hosts, as well as aspects of host–pathogen interactions which provide important insights into more general ecological dynamics.

Under the extreme selective pressures imposed by meso- and bathypelagic environments, a vast array of bizarre and wonderful creatures has evolved, displaying behaviors and associated morphological adaptations that are almost beyond our ability to imagine. Among the highly diverse products of this evolution in the great oceanic depths, few are as surprising and spectacular as the deep-sea anglerfishes. A rigorously tested systematic hypothesis of relationships allows for a precise reconstruction of aspects of character evolution, which in turn will cast light on broader evolutionary processes that have taken place within the Ceratioidei, and perhaps within the deep-ocean ecosystem as a whole. This chapter is devoted to that effort. It discusses ordinal relationships, subordinal and familial relationships, giving a key to the major subgroups of the Lophiiformes, looking at the relationships of Ceratioid families and genera, characters and character states, characters restricted to metamorphosed males, characters restricted to larvae, and sexual parasitism.