Search Results

This introductory chapter expands on three important themes that form the backdrop of this book's study: nutrition touches and links all living things; nutrition is complex; and there have been benefits both from the highly specific and detailed approach of applied nutritional sciences and the simplified, general approaches adopted in the ecological sciences. At the most conspicuous level, nutrition is a primary factor defining the geographic distribution and temporal pattern of activity for many animals. Achieving nutritional homeostasis involves a complex interplay between multiple and changing nutrient needs and variable foods. The detailed studies of human and animal nutritionists have yielded a wealth of information for deriving dietary recommendations for human health, formulating animal feeds, designing dietary regimes for captive animals, supplementing the nutrition of free-ranging animals—and many other important practical applications.

The estimated number of undernourished people around the world has increased to nearly 923 million and is projected to rise with increasing food prices. A large majority of those affected live in India. This chapter examines one of the key efforts to address undernutrition in a targeted and rational manner in India. The resulting project, the Tamil Nadu Integrated Nutrition Project (TINP) was rational in that it was based on a combination of two Western-based scientific and modern disciplines, namely biomedical and health economic models. TINP was funded by the World Bank and has often been referred to as one of the most ‘successful’ nutrition projects in the general nutrition literature, so the way it was designed and implemented is of particular interest. It is argued that there is a mismatch between how malnutrition is defined, measured, and evaluated by the World Bank, and how it is lived and experienced in affected communities. While the biomedical approach to undernutrition might be suitable in the setting of a clinic, it is problematic when exported to stand-alone community nutrition projects such as TINP.

This chapter discusses the Geometric Framework (GF) for nutrition. GF satisfies the multiple-food-components requirement using a simple device known as a nutrient space. A nutrient space is a geometric space built of two or more axes, where each axis represents a food component that is suspected to play a role in influencing the animal's responses to its environment. In most cases, these food components will be nutrients but this is not invariably the case. The nutrient space provides the common context in which to describe the pertinent aspects of the animal, its environment, the interactions between animal and environment, and the consequences of these interactions.

This chapter reviews the diversity of feeding habits among birds and the consequences for their nutritional ecology. Different digestion strategies are also emphasized. Food selection is often treated as a challenge of acquisition, but it is also a problem of utilization, processing and digestion of food. What animals eat and excrete shapes their role in ecological communities and determines their contribution to the flux of energy and materials in ecosystems. The balance between energy acquisition and expenditure is critical for survival and reproductive success. Because energy intake and expenditure integrate all aspects of an individual's life, changes in energy management are closely tied to all aspects of its life-history, including diet quality, nutritional requirements, allocation of time, and body plan.

This chapter focuses on how animals are able to regulate their intake and use of multiple nutrients. To regulate the balance of nutrients eaten, an animal needs to assess the composition of available foods in relation to its nutritional requirements. Integration of information about food composition and nutritional state occurs both at the periphery, by nutrient-specific modulation of taste receptors, and more centrally as signals from systemic and peripheral sources converge onto the neural circuits that control feeding behavior. Meanwhile, postingestive regulatory responses can assist in rebalancing an imbalanced nutrient intake. Once digested and absorbed across the gut, nutrient supplies can be further rebalanced by differentially voiding excess nutrients and conserving nutrients that are in limited supply.

This chapter examines the relationships between nutrition, life span, and sex. It considers the view that dietary restriction without severe malnutrition prolongs life. It is generally believed that the benefits of dietary restriction arise from eating fewer calories. However, Geometric Framework experiments on insects in which the effects of macronutrients have been separated indicate that, rather than calories, a key determinant of the relationship between diet and longevity is the balance of protein to nonprotein (fat and/or carbohydrate) energy in the diet. Meanwhile, the presumption in much of life history theory that life span and reproduction trade off against each other for limiting resources is shown to be too simplistic. These two life-history variables certainly have differing nutritional optima, but they can be dissociated and do not inevitably trade off. Reproductive senescence and aging may proceed at different rates in males and females, as predicted by sexual selection theory.

This chapter assesses the consequences of individual nutrition for populations and the assemblages of species that comprise ecological communities. However, the ecological consequences of nutrition are not restricted to the effects of diet on individual organisms but include as well the direct and indirect interactions occurring among individuals within populations and between species. Understanding the complex network of interactions that produce food webs and structure ecosystem dynamics requires the understanding of the participants' differing nutritional requirements, priorities, and regulatory capacities. Geometric Framework analyses have shown that these features differ between species and across trophic levels. Nutritional space is one part of the fundamental niche of an organism, and there is a need to integrate nutrition with the biophysical ecology of organisms. Evolutionary processes also need to be taken into account, and agent-based models offer promise toward development of a new understanding of the evolutionary ecology of nutrition.

This chapter explores the methods of nutritional geometry on the modern human diet, applying the geometric approach to an analysis of a key aspect of human nutrition: the topical subject of human obesity. This analysis leads to three conclusions. First, the available evidence suggests that humans can regulate macronutrient intake, but that the intake target contains a built-in component for fat storage. Failure to use this stored fat promotes obesity. Second, when humans are faced with imbalanced diets, protein intake is prioritized. When the ratio of protein to carbohydrate in the diet is lower than optimal, it is easier to gain the required amount of protein—and hence overconsume fat and carbohydrate—when foods are high in energy density, present in great variety, and easily available throughout the day. Lastly, the regulation of nutrient intake in humans has evolved “assuming” a higher level of energetic expenditure than is usual today.

Although agriculture acted as a spur to many aspects of social and technological development, increasing reliance on a narrow range of food crops had many downsides that sometimes caused people to revert to hunter gathering. The restricted nutrient content of some crops, especially cereals, led to a reduction in human stature and an increase in degenerative diseases. People adapted both behaviourally and genetically to their increasing reliance on crops and livestock. Genetic changes in various populations included reduced maxillo-facial structures, lactose tolerance, malarial resistance, and partial resistance to zoonoses. Although many of these changes had an adverse impact on human wellbeing at the individual level, the greater size and techno-social complexity of agrarian based societies enabled them to out-compete hunter-gatherers. Despite their superior individual fitness, hunter-gatherers were fewer in number, less well organized, and lacked access to new technologies developed by their sicklier but formidably equipped agrarian neighbours.

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 examines Aristotle's claim that the soul is an inner principle of change, against the background of his account in the Physics of nature as an inner principle of change. That for Aristotle, the study of the soul is part of the study of nature is clear already from the opening lines of the De anima, where he announces that ‘knowledge of the soul seems to contribute greatly to all truth but most of all the truth in relation to nature: for the soul is such a thing as a principle of animals’. The study of the soul is valued, then, for its contribution to our knowledge of nature. The reason for that claim is in turn that the soul is such a thing as ‘a principle of animals’. Aristotle thinks that the soul really is a principle of animals. The ‘such as’ here serves rather to put epistemic distance to the claim: we do not yet know what it means for the soul to be a principle, so the vagueness is appropriate. The chapter seeks to overcome some of that vagueness.

The first section of this chapter focuses on direct and indirect approaches to the demography of malaria. The problems associated with using cause of death statistics to assess mortality due to malaria are discussed, with particular emphasis on the towns of Sermoneta and Grosseto. The second section considers the interactions of malaria with other diseases, such as syphilis, smallpox, gastro-intestinal diseases, tuberculosis, and pneumonia. This section also includes a detailed discussion of quartan fever (caused by Plasmodium malariae) in antiquity. The third section studies the relationship between malaria and human nutrition. The fourth section compares the historical mortality patterns in certain parts of two different countries which had endemic malaria, namely central Italy, East Anglia, and southeast England. The demographic effects of the interaction in central Italy between Plasmodium falciparum and Plasmodium vivax are analysed as well as the role played by Plasmodium vivax on its own in the mortality patterns of the early modern English marshlands.

Gives perspective to the debate over living standards during industrialization by examining health and nutrition over the past 1200 years using stature either recorded on military records or inferred from skeletal remains. From an average of 173.4 cm in the early Middle Ages, the heights of men fell approximately 6.4 cm, reaching a minimum sometime in the seventeenth or eighteenth century, and recovery to levels of a millennium earlier was not attained until the 1920s. The decline that began in the late Middle Ages may be linked with a cooler and more variable climate; growing inequality; urbanization; fluctuations in population size that impinged on nutritional status; the global spread of diseases associated with European expansion and colonization; and wars over state building or religion. The upturn well underway by the nineteenth century was associated initially with dietary improvements and later with reduced exposure to disease related to public health measures and better housing.