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It is demonstrated that the fundamental problem of global biodiversity regulation is similar to the bargaining problem analysed by Nash, Rubinstein, and others. There are benefits from global land conversion, and there must be agreement on their distribution before the conversion process can be halted. Since the institutions addressing global biodiversity problems are either highly ineffectual (benefit-sharing agreements, prior informed-consent clauses) or very extreme (incremental cost contracts), the biodiversity bargaining problem remains unresolved. For this reason it is anticipated that sub-optimal conversions will continue to occur, as a way of protesting the ineffective and unfair approaches employed in addressing this problem to date.

This chapter explores the following question: How can our knowledge of global biodiversity patterns and our understanding of underlying processes and drivers help us to apprehend, project, and reverse the trajectory of large-scale biodiversity loss? It examines global richness patterns and biodiversity hotspots on land and in the sea together. It looks at these patterns through two different lenses: (1) total species richness, and (2) relative richness across taxa. It argues that biodiversity patterns are not a static feature. In recent decades and certainly throughout Earth's history, the global magnitude and distribution of biodiversity has been dynamically changing in response to various environmental drivers, many of which are now affected by human activities. This means that the future of biodiversity is in our own hands, and future trajectories will largely depend on how we choose to constrain or manage the cumulative impacts that arise from our actions.

This concluding chapter summarizes the book's major findings and presents some final thoughts. Among these findings is clear evidence that global biodiversity organizes into distinct patterns within four major biogeographic realms: coastal, pelagic, deep ocean, and land. Taxonomically distinct species groups tended to show similar patterns of biodiversity at large scales within each of these four realms. A body of theory was devised that might explain observed biodiversity patterns within and across taxa. This theory suggests that only two variables are required to predict the majority of first-order patterns of biodiversity on our planet: ambient temperature and community size. Temperature primarily affects the rate of community turnover and the speed of evolution, while community size determines the number of individuals on which evolutionary processes can act.

This introductory chapter provides an overview of the book's main themes. The book aims to construct an integrated understanding of large-scale patterns of marine and terrestrial biodiversity at regional to global scales. It asks the following: How is the global richness of species organized, and how does it vary across taxa and through space and time? What are the environmental factors that may drive this variation and to what extent are these factors influenced by human perturbations? Can we explain this bewildering variety from simple ecological theory and provide a more mechanistic understanding of the fundamental distributional patterns of life? A key premise of the book is that a more comprehensive understanding of global biodiversity can be gained only by overcoming a disciplinary divide that has long separated the study of biodiversity on land and in the sea. The chapter also provides a brief history of biodiversity research.

This chapter develops a body of theory to capture and test the key processes governing the global distribution of biodiversity. From this theory, it devises a spatial metacommunity model that enables the reconstruction of documented patterns of species richness from first principles and the prediction of their major features. The chapter starts with a simple, flexible, and tractable framework that can be built on and expanded in order to test competing hypotheses. This modeling approach may be described as an experimental toolbox for global biodiversity patterns. The aim is not necessarily to achieve the highest predictive power, but to explore the possibility space of global biodiversity patterns and their drivers.

The previous chapter developed a global theory of biodiversity incorporating gradients in ambient temperature and habitat area or productivity. It showed that a metacommunity model implementation of the theory can reproduce first-order patterns of declining species richness from the tropics to the poles in an idealized cylindrical ocean. This chapter tests the theory in a more realistic setting by fitting the neutral-metabolic metacommunity model to a global equal-area grid with a more realistic spatial structure. The rationale here is to explore whether the communities that evolve in a simple theoretical model can reproduce observed patterns of species richness in the real world, and reconcile the contrasting patterns seen in coastal, pelagic, deep-sea, and terrestrial habitats.

This chapter considers the driving factors that may cause global patterns of biodiversity to exist. The goal is to confront published hypotheses about putative drivers of diversity with comprehensive empirical information on the environmental predictors of diversity on land and in the oceans. It argues that the diversity of life on land is primarily related to the availability of ambient energy, measured as temperature or potential evapotranspiration (PET), in combination with sufficient moisture, habitat area, and complexity. Thus, there is a fundamental similarity between primary correlates of diversity on land and in the sea, considering similar primacy of ambient energy and habitat as leading predictors of species richness.

Tropical rain forests are disappearing rapidly as a result of increasing human encroachment. During the past century, tropical rain forests have been reduced to about half of their original area. And the rate of deforestation is accelerating, fueled by population growth in developing countries and resource demands in the developed countries. The remaining forests are subject to increasingly intensive human use. Deforestation, fragmentation, and exploitation cause a plethora of problems, including soil erosion; siltation of rivers, lakes, and estuaries; increased flooding and droughts; release of carbon dioxide and other greenhouse gases into the atmosphere; and loss of species. In recent years, these problems have become the subject of international concern. This book focuses on the loss of biodiversity in tropical rain forests and on the role of protected areas in stemming the loss. This chapter examines the meaning of biodiversity and the history of the park movement in the tropics. What began as protection of habitat through the exclusion of people has transformed into sustainable use of biological resources. This new emphasis provides local control of important resources and greater income, but does it conserve habitat and species? We will argue that a renewed focus on protected areas as the primary storehouse of biodiversity is needed. We will also make the case for a focus on the tropical rain forest biome and will conclude with an overview of the rest of the book. In its strict sense, biodiversity refers to the “variety and variability among living organisms and the ecological complexes in which they occur” (Office of Technology Assessment, U.S. Congress, 1987:3). This definition can be extended both downward to cover genetic variability within a species and upward to include habitat and ecosystem diversity. practical terms, however, biodiversity is most profitably expressed as species diversity (weighted for rarity, endemism, and taxonomic distinctiveness, if necessary) at the landscape level (see chapter 6). We adopt this definition of biodiversity. During the past few years, attempts to link rain forest protection with sustainable development have led to a noticeable expansion of the meaning of the phrase “biodiversity conservation.”