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The chapter summarizes the history of recent scientific understanding of food webs, particularly shallow water food webs. The chapter outlines a history of key papers ranging from Elton to the most recent synthetic studies of meta-analysis of multiple food webs in many ecosystems. Changes in general organizing principles over time and conflicts with recent understanding are emphasized including an outline of the considerable progress over time and hope for an emerging discipline that takes advantage of emerging multidisciplinary tools and collaborations.

This chapter summarizes research on the anatomy and physiology of the House Sparrow based on organ systems: integumentary, skeletal, muscular, nervous, endocrine, circulatory, respiratory, digestive, excretory, and reproductive. The energetics of the species is also discussed, as well as body mass and composition.

This chapter shows how climate might influence seabirds directly through variations in temperature and wind. It also provides an overview of the potential indirect impact of climate variability on North Atlantic seabird populations. Seabirds are sensible to climate change either positively as shown by the extension of the fulmar population, or negatively as shown by the Atlantic puffins. Thanks to their position as top predators, their response to climate change is a good index of its effect on the whole food web.

This chapter considers methods used to study the physiology and genetics of birds. It describes methods for obtaining samples of blood and tissue from wild birds, experimentation, anaesthesia, administration of substances to birds, implants, and laparatomy. The legal and ethical considerations involved in the use of invasive and experimental methods are discussed in detail. The uses of materials gathered from such techniques in studies of ecotoxicology, endocrinology, energetics, and molecular genetics are described.

Studies on lakes provide some of the most complete investigations on the structure, dynamics, and energetics of food webs encompassing organisms from bacteria to vertebrates. The life cycle of organisms in temperate lakes is adapted to a highly seasonal environment. Food web interactions in these lakes depend on the seasonal overlap of the occurrence of potential prey, competitor, or predator species. This seasonal overlap (i.e., the match-mismatch of food web interactions) depends strongly on the seasonal dynamics of the physical environment of lakes, such as temperature, light availability, and mixing intensity. Consequently, climate variability influences food web interactions and hence the structure, dynamics, and energetics of lake food webs. This chapter provides examples and discusses the importance of seasonality for the understanding of various aspects of lake food webs and the impact of climate variability thereon.

This chapter provides a summary of the topics covered by the present volume. The summary serves the purpose of clearly showing how different chapters fit together in a general framework with respect to model approaches as well as results obtained. Reading this summary chapter will show readers the different types of community modules that will be analyzed as well as provide a clear impression of the results and insights that presented in this book. Topics discussed include biomass overcompensation, ontogenetic (a)symmetry in energetics, emergent community effects of biomass overcompensation, ontogenetic niche shifts in consumer life history, ontogenetic niche shifts in predator life history, competition between consumers with and without ontogenetic niche shifts, and ontogenetic (a)symmetry in energetics and population dynamics.

Orangutans have the longest interbirth interval of any mammal, with existing data suggesting that these intervals may be significantly longer in Sumatra than in Borneo. This finding presents a paradox because our models of reproductive ecology suggest that the higher habitat quality of Sumatra should lead to shorter interbirth intervals. This chapter explores this intriguing difference between Sumatran and Bornean orangutans by detailing the available evidence on how orangutan reproduction is influenced by ecology and life history. Data are evaluated in light of the models, mechanisms and hypotheses by which energetics influence reproduction in apes and humans. The chapter makes recommendations for future research that will lead to a more thorough understanding of orangutan reproductive ecology. New hypotheses about acute vs cumulative effects of energy on ovarian function, the magnitude of the shift in energy intake, and the role of developmental plasticity in orangutan reproductive functioning are also presented.

This chapter provides two ethnographic examples of anthropologists reflexively incorporating Melanesian aesthetics and energetics into their interpretations by making distinctive borrowings from Melanesian practices. In James F. Weiner's portrayal, Foi perceive the world as constituted by various forms of ‘a flow of vital energies, forces and relationships’. He suggests that men and women engage flow in distinctive ways. Foi takes human sociality, its ‘rules’, as ‘given’ or ‘innate’. Marilyn Strathern's The Gender of the Gift: Problems with Women and Problems with Society in Melanesia presents an original line of theoretical reasoning prompted by an ‘impasse in [the] comparative anthropology of Melanesia’. Mt Hagen is the ground by which The Gender of the Gift is figured. Strathern shares Ongka's awareness that exchanges are dependent upon producers: a husband with moka ambitions has to be an equally enthusiastic sweet-potato gardener, helping his wife to provide fodder for the pigs she will grow into prestigious gifts. An effect of The Gender of the Gift has been that much of what it has to teach has been incorporated by Melanesianists.

This chapter begins with the trophic model of Hairston, Smith, and Slobodkin and the food-web model generated by Cohen. It explains why, even in a desert, such generalities are inappropriate. Desert food-webs are much more complex than the ones described by previous researchers, and indicate that: energetics is not necessarily the most appropriate way to view food-webs; interaction webs (describing population effects) and descriptive webs (quantifying energy and matter flow) are not necessarily congruent; and consumer regulation of populations need involve little energy transfer and few feeding interactions. Most importantly, if the animals at the bottom of the chain are small, then more steps can be incorporated as one moves up the trophic pyramid. The important roles of disturbances and decomposition are considered.

This chapter outlines environmental and conservation concerns that underlie the research described in this book. There are examples of observations of otters of different species in the wild, main threats to species including different kinds of pollution and exploitation, historic declines and recoveries, and public interest. Main questions concerning otter ecology and behaviour are outlined, especially the factors that limit their numbers, present knowledge of population changes and causes of declines, habitat, resource availability and usage by otters, the role of energetics in their ecology, their role in ecosystems, and methodologies for study in the wild.

This chapter describes otter phylogeny, including the latest analyses of mitochondrial DNA. They are Mustelids, originating some 11-14 million years ago in the Miocene in south-east Asia, main branches being Lutra and Lontra. A rapid species divergence was followed by long-persisting genera. Some intra-specific variation is described. Central questions posed in this book address the relationship between resources and otter numbers, energetics relating to resource exploitation (with thermo-regulation in cold water), and social aspects of distribution in their habitat, mortality, and reproduction. Research methodology to study these questions is described, including individual recognition in the field, trapping, radio-tracking, and pitfalls when using indirect methods such as faecal analysis and distribution of scent-marks. Some study areas are described.

This chapter describes foraging behaviour, and the success rates and factors that influence this. Diving of Eurasian and sea otters is quantified (depths, timing) and analysed in some detail. Some species fish cooperatively. Sea otters use tools for foraging. Otters hunt at times (time of day, tide) and places (depths, aquatic vegetation) when prey are optimally available i.e. inactive. There is a clear tendency to hunt prey in patches. Analysis of energetics of foraging suggests that most variations in foraging effort are caused by variations in water temperature. At low temperatures, otters fish close to their energetic limits in a high-risk strategy. Young of several species require 1-2 years to attain adult foraging efficiency.

The application of computational techniques to polymorphic systems is reviewed. Topics covered include the energetics of molecular geometric features (bond lengths, bond angles, torsion angles) and the energetics of intermolecular interactions of various types. Methods and techniques for the presentation of polymorphic structures are described, followed by some historically important early examples of conformational polymorphism. The latter subject is treated in light of recent developments, including some exemplary studies of conformational polymorphism and the prototypical example of “ROY” is discussed in detail. The computational prediction and comparison of polymorphs is discussed in the framework of the computational prediction of crystal structures. Methods discussed on polymorphs include the comparison based on geometric criteria, comparison based on Hirshfeld surfaces, a comparison based on energetic environment, comparison of X-ray diffraction patterns, and the use of partitioned lattice energy to investigate the details of similarities and differences in polymorphic structures.

The most remarkable feature of the physical content of Heinrich Hertz's book Principles of Mechanics is that it is a mechanics without forces. The concept of force and, in particular, of gravitation acting at a distance was introduced by Isaac Newton. This was strongly criticised by the Cartesians who argued that all interactions could and should be explained in terms of contact forces. Hertz's view of the relation between the concept of force and the concept of constraint was a total reversal of that of Siméon-Denis Poisson and William Rowan Hamilton. According to Hertz, connections are the physically primary concept and forces are only derived idealized epiphenomena. This reversal was part of a larger rejection of Laplacian physics. This chapter also discusses James Clerk Maxwell's theory of electromagnetism, distance forces, arguments against atomism, and the emergence of energetics as an alternative to an atomistic, force-based mechanical conception of physics.

A balance of energy gain and use is needed during migration to safeguard against starvation and to minimize the costs of body mass overloading due to excessive lipid deposition. This chapter addresses how this is achieved throughout the four principal stages of animal migration: preparatory, movement, stopover, and arrival. It first discusses how lipid loading may be limited by ecological (e.g., food abundance), physiological (e.g., digestive capacity), and geomagnetic factors, as well as by annual routine events (e.g., the timing of feather moult) and the animal's migration strategy. The chapter then deals with environmental effects on energy use and discusses the energetics of barnacle geese (Branta leucopsis) migrating from Svalbard to Scotland. It proposes that combining accelerometry to provide behavioural data with estimates of metabolic rate may substantially improve our understanding of the causes, mechanisms, patterns, and consequences of animal migration.

Research into how muscle plays these roles and the limitations of its ability in each regard requires that we measure directly or indirectly the energy changes involved; this has been recognized for at least a century. These experimental activities and the interpretation of the results obtained comprise the science of muscle energetics. This chapter discusses the main forms of energy which are relevant to consider in these contexts. For example, the flow of mechanical energy to or from the muscle is found from measurements of force (P, Newtons) and of movement (dL, metres). Work is the integral of force with respect to length over the period of study.