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This chapter contains a theoretical analysis of the rise and fall of clusters. It is shown how a major technological innovation sets a process of creative destruction into motion, where new clusters appear and replace clusters based on obsolete technologies. In the last stage when the cluster matures, it either achieves a national or international leadership in a given sector or technology. The decisive element appears to be a different institutional framework. Using simulation techniques, it is shown how policies that support firm-based micro-level incentives seem to be critical rather than policies aimed at strengthening the ‘carrying capacities’. Most European policy makers overemphasize the latter type of policies as a means to initiate cluster emergence and growth.

This chapter attempts to calculate the grain production and carrying capacity of Attica by analyzing five key variables: land, use of the land, crop yields, population, and consumption. Previous scholarly attempts to calculate these variables are surveyed. As part of the study of land, soil and climate are examined, as well as the extent of arable space, taking into account the use of terracing. As part of the study of land use, the conventional and revised models of Greek farming are compared. The results confirm the continuing usefulness of the former, which would indicate that half of the cultivable land of Attica required fallowing each year, and that natural fertilizers were insufficiently available to overcome this need or to escape relatively low yields. It is argued that the figures of imported grain transmitted by Demosthenes are reliable, and that recent attempts to demonstrate the opposite are unsatisfactory.

There is an inherent tension between human impact (the product of the size of the human population, people's level of food consumption, and the technology used to produce food) and the ability of the environment to supply food (the human carrying capacity). The “zone” is the place where human impact overlaps carrying capacity, either for a given location or for the whole planet. The way in which we understand and respond to the zone depends on basic assumptions about natural resources and human nature, and it is at the core of defining and solving the food crisis. This is illustrated using a calculation of human carrying capacity based on water needed to grow rice to provide calories for the human population.

This introductory chapter describes the outline, focus, and themes of the book. The book describes the genetic and linguistic diversity in the key region of Northern Island Melanesia. Recurrent themes of the book are laid out. These are: the influence of the island biogeography (a series of stepping-stone islands extending from Southeast Asia into the Pacific); the dynamics of small populations (even some of the larger islands had carrying capacities of under 1,000 people in pre-Neolithic times); very limited marital migration distances in inland (bush) communities vs. more extensive marital migration rates along shoreline communities; intensifying mobility after the isolation of initial settlement, aided by better seafaring technology in the Holocene; and later immigration of distinct peoples from Island Southeast Asia, who spoke Austronesian (Oceanic) languages and settled along the shorelines and the small islands, so that language distinctions are associated to a degree with the pattern of diversity. The succeeding chapters are summarized.

This chapter provides an overview of sustainability and how it can be maintained in a world of limited resources. It posits some definitions of the term “sustainability,” noting that any workable definition thereof requires some combination of ethical, social, economic, environmental, and operational components. Two questions thus arise in obtaining a definition of sustainability: one of equity, the other of costs; and the two are closely related. The chapter then turns to the issue of defining a list of basic requirements for human survival, before turning to the larger issue of the Earth's “carrying capacity,” so to speak, and how it involves social, ethical, and economic as well as physical and biological considerations.

The estimated carrying capacity of the Valley of the Kings is about a thousand visitors per hour. This is calculated with reference to parking areas, average length of visit, and waiting times at tomb entrances. Surveys of visitor numbers reveal consistent peak periods at specific times of the day. The number of visitors per day, and the flow of visitors through the site, can be controlled in several ways: allowing a maximum number of visitor in the Valley at any one time; restricting the size of tour groups; expanding the opening hours; enforcing parking restrictions; building full-size replicas of specific tombs; using a signaling system to indicate when particular tombs are temporarily full of visitors; ticketing systems that would encourage visits to less popular tombs; forbidding guides to lecture inside tombs; maps and signs; and physical barriers to control lines outside tomb entrances.

This chapter examines the question of how many people can live in the land of Israel. It considers the implications of the present food supply on potential population levels. It begins by addressing the question of how many people lived in Israel during its different historic periods before the advent of global trade that allowed for the meaningful importation of calories. It then reviews the initial deliberations about the land's potential absorptive capacity. Self-sufficiency was the starting point for traditional discussions about carrying capacity levels. A society's ability to provide itself with energy and food was deemed fundamental to its long-term survival. For a brief period during the first half of the twentieth century, whether the land of Israel could provide food and a decent living for a rapidly growing population was the subject of fierce debate. The argument still casts a shadow on present discussions of carrying capacity.

Chapter 4 looks at the scientific struggle to determine carrying capacities and the political struggle to impose them on ranchers in the form of stocking rates. It took the Forest Service decades of concerted effort just to develop a basic inventory of its rangelands, and even when data were available the problem of converting an ever-changing volume of forage into a fixed number of livestock was a matter of chronic uncertainty and debate. Fixing stocking rates to match average conditions ensured that there would be excess grass in wet years and excessive livestock in dry ones; perennial disputes with ranchers predictably ensued. Publicly, the agency made bold claims about the condition of the nation’s rangelands, invoking solid-looking numbers to defend itself against ranchers, rival agencies and critics in Congress. Internally, however, the scientists conceded that determining carrying capacities was fraught with problems. Then, at mid-century, an apparent solution was found: economical, standardized methods of quantifying both the successional stage and the volume of forage of a given range. It was not actually a solution, as would become apparent over time, but it represented an important final step in consolidating the authority of range science.

The chapter focuses on the sustainable use of land which is fixed in availability and has competing uses for meeting the requirements of any economy. As agriculture for food supply is the most critical use of land it outlines the theory of land use and rent with reference to soil or land quality and defines the carrying capacity of land in terms of providing life support to people in calorie units. It critically discusses the issue of food security with reference to the adequacy of carrying capacity of land and points to both the challenges of distribution as well as augmenting carrying capacity using biotechnology and developing genetically modified crops. It further discusses the actual pattern of land use and land degradation in India, and their causal factors, like soil erosion, chemical and physical degradation of land, poverty, overpopulation and dependency on ecologically fragile resources with their policy implications.

Chapter 2 explores the history of how population came to be known as an environmental problem, emerging through debates about eugenics, war, geopolitical stability, and land use. I begin the chapter by exploring how population was first identified as a central problem of state-making and security, and its role in the evolution of ecological sciences. Next, I trace the ways the environmental sciences and population politics have entwined and overlapped in subsequent decades. Throughout, I analyze the ways knowledge production linking population to environmental problems moved between political advocacy motivated by concerns about war and geopolitical security, concerns about planetary limits, and a site of scientific knowledge development and struggle.

This chapter addresses the question of how many people should live in the land of Israel. Israel “appropriates carrying capacity” from other places on the planet. An implicit assumption of present strategies holds that there will always be sources “out there” able to send Israel raw materials and food, along with sinks for absorbing its wastes. In the long run, this is a dangerous assumption. Limiting calculations to the physical dimensions of carrying capacity is a highly superficial exercise that emphasizes quantity over quality of life. Israel must begin to consider what its “optimal population levels” should be as opposed to what its “maximum population levels” might be. The future will be more agreeable and healthier for forthcoming generations if they are bequeathed the best possible life rather than the maximum number of countrymen with whom to compete for finite space and resources.

An often quoted passage of Arthur Conan Doyle's story "Silver Blaze" makes the point that the absence of data can be a datum. When the mystery of the purloined racehorse seems insoluble, Police Inspector Gregory asks Sherlock Holmes:… "Is there any point to which you would wish to draw my attention?" "To the curious incident of the dog in the night-time." "The dog did nothing in the night-time." "That was the curious incident," remarked Sherlock Holmes…. The dog that does not bark attracts no attention to itself. It takes insight to recognize that a nonhappening can be an alarm. Herman Daly showed a Holmeslike insight when he called attention to the bark that was absent from a would-be authoritative study made by a group of economists reporting to the prestigious National Research Council in 1986 on population growth and economic development. In 108 pages of text there is not a single mention of carrying capacity, a concept that should be central to all discussions of population and environment. It is as though gravity were left out of a treatise on the dynamics of the solar system; or assets and liabilities were left out of a textbook on business accounting. If civilization survives another century, and if there are still economists, a history of what will then be called "modern economics" may well begin with a belittling account of the "premodern" economics of the twentieth century in which carrying capacity plays no role. Nothing shows so well the impermeability of the barriers between academic disciplines as the silence of economists about a concept that dominates discussions of game management, a discipline concerned with population and environment problems as they affect animals other than Homo sapiens. Economists, dealing only with human populations, probably unconsciously embrace the human exemptionist doctrine (Chapter 15), though their commitment is seldom no more than implicit in their statements (Box 20-1). Two serious criticisms can be leveled against most of the authors quoted in the box. First, it is obvious that they desperately yearn for a world without limits. This is particularly evident in the last quotation, by Gro Harlem Brundtland, who chaired the United Nations commission that issued this statement. One can praise the heart of the commission without agreeing with the head.

“Dystopia at the Doorstep” describes the direction humanity is heading, should trends of growing human numbers, spreading consumerism, intensifying food production, and expanding global trade continue. Two perspectives on these trends are presented: first, that continued growth risks breaching biophysical limits and causing collapse; and second, that with technological and managerial transitions the coming billions of people can enjoy a good standard of living. Instead of taking sides in this classic debate, the chapter argues that staying with the growth trends does not turn out well: the dystopia at the doorstep is a humanized planet, of threadbare biodiversity, dominated by domestic animals, crops, and a global cadre of generalist species. A detailed examination of industrial agriculture and its massive impact on the natural world is then pursued. The chapter contends that humanity has a different choice than continuing to extend its carrying capacity by augmenting food production. We can humanely curtail our numbers, along with de-industrializing food production and allowing global trade to take second place to local ways of organizing economies. This path can be grounded in the desire to inhabit life’s plenitude, rather than plunging toward a colonized planet repurposed and managed as a human plantation.

There are several reasons for conducting a habitat analysis and identifying the environmental (habitat) characteristics that a species associates with. (1) Knowledge of a species’ habitat requirements is crucial in restoring and managing habitat for the species. (2) Carrying capacity informs us about the potential (or lack thereof) for future population growth based on resource availability. Knowledge of a species’ habitat requirements allows us to interpret the importance of carrying capacity in a habitat-specific way. (3) The study of species interactions and the potential for species coexistence is supported by having knowledge of the habitat of each species under investigation. (4) Habitat preference and selection as eco-evolutionary processes continue to be widely studied by ecologists—interpretation of the results of such studies is best done with knowledge of the species–habitat associations. Such knowledge can also be useful in the design of preference and selection studies. (5) Knowledge of species–habitat associations can also be of great use in selecting the environmental variables to use in species distribution models. All five of these goals point to the great utility of conducting a habitat analysis as a supporting investigation or as a way to obtain knowledge to put to a practical purpose.

The concept of optimal population has been floated since antiquity but is it sufficiently robust to serve as the basis for policy? This chapter analyzes four approaches: classical (Wicksell) based on average not marginal utility; ethical, which brings in the Repugnant Conclusion; natural resource/carrying capacity; reproductive and fiscal externalities. All have serious weaknesses which suggest caution in population policy matters. Some of the difficulties are separating static and dynamic optimality with changing technology and preferences, measurement of economies and diseconomies of scale, incorporating spatial and inter-temporal distributional issues, and attributing utility to potential persons. The growth and decline of population may be more suitable for analysis than the level.

Ecological character displacement is phenotypic evolution wrought or maintained by resource competition between species. By resource competition, I mean the negative impact of one species (or individual) on another arising from depletion of shared resources. Character evolution driven by other mutually harmful interactions, such as intraguild predation or behavioral interference, is not included in the current definition of character displacement but perhaps should be in future. For the purposes of this chapter, however, character displacement is synonymous with the coevolution of resource competitors. The idea that competition between species has a significant impact on character evolution has a lively history. Prior to about 20 years ago, competition was seen as one of the major factors responsible for the evolution of species differences, particularly in traits affecting resource exploitation (e.g., body size, beak shape). The idea is seen again and again in the early literature not because it was rigorously established but because it so readily accounted for observed patterns of species differences in nature. Support for the idea began to slip soon afterward, however, as alternative hypotheses were developed and as it became clear that the quality of most of the available evidence was poor. More recently, the idea has become respectable again as evidence from several systems has become more solid. My goal in this chapter is to present an overview of some of this evidence and how it has affected our understanding of the process. I begin with a brief historical sketch of character displacement and the expectations from theory. I then present a few of the highlights emerging from observational studies of patterns suggesting character displacement, their limitations, and their implications. I follow with an overview of recent experimental work that complements studies of pattern but goes beyond them by testing novel predictions of character displacement hypotheses. I end with suggestions about where the most significant future discoveries lie. The history of ideas on competition and character divergence begins with Darwin (1859), who regarded interspecific competition for resources as a fundamental and ubiquitous agent of divergent natural selection: “Natural selection … leads to divergence of character, for more living beings can be supported on the same area the more they diverge in structure, habitats, and constitution”.

“Welcoming Limitations” argues for shifting perspectives on carrying capacity away from the definition of the maximum number of people the planet can support toward an ecological touchstone: the number of people an ecologically sound food system can support. Since the industrial food system is the most destructive, revamping the food system is imperative. This has implications for human population size. In line with Paul Ehrlich and others, the chapter argues that a population of around 2 billion is a defensible goal, enabling the conservation of biodiversity, an interconnected global civilization, and the co-flourishing of humanity and biosphere. This conclusion raises the specter of "the population question," wherein even mention of overpopulation is assailed as politically insensitive. Concerns are allayed by reframing the population question, including: redefining overpopulation as a global issue and not strictly a developing world one; clarifying that population size is a significant driver of excessive consumption, and not a variable independent of overconsumption; and countering the silence surrounding overpopulation, endeavoring to promote broad agreement about the population problem through thinking about it from new angles. Reframing the population question is followed by a discussion of a human-rights framework through which population can be stabilized and slowly reduced.