Perspectives in Ecological Theory

Perspectives in Ecological Theory

Copyright Date: 1989
Pages: 408
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    Perspectives in Ecological Theory
    Book Description:

    This volume presents an overview of current accomplishments and future directions in ecological theory. The twenty-three chapters cover a broad range of important topics, from the physiology and behavior of individuals or groups of organisms, through population dynamics and community structure, to the ecology of ecosystems and the geochemical cycles of the entire biosphere.

    The authors focus on ways in which theory, whether expressed mathematically or verbally, can contribute to defining and solving fundamental problems in ecology. A second aim is to highlight areas where dialogue between theorists and empiricists is likely to be especially rewarding. The authors are R. M. Anderson, C. W. Clark, M. L. Cody, J. E. Cohen, P. R. Ehrlich, M. W. Feldman, M. E. Gilpin, L. J. Gross, M. P. Hassell, H. S. Horn, P. Kareiva, M.A.R. Koehl, S. A. Levin, R. M. May, L. D. Mueller, R. V. O'Neill, S. W. Pacala, S. L. Pimm, T. M. Powell, H. R. Pulliam, J. Roughgarden, W. H. Schlesinger, H. H. Shugart, S. M. Stanley, J. H. Steele, D. Tilman, J. Travis, and D. L. Urban.

    Originally published in 1989.

    ThePrinceton Legacy Libraryuses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These paperback editions preserve the original texts of these important books while presenting them in durable paperback editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.

    eISBN: 978-1-4008-6018-0
    Subjects: Ecology & Evolutionary Biology, Biological Sciences

Table of Contents

  1. Front Matter
    (pp. i-iv)
  2. Table of Contents
    (pp. v-2)
  3. Introduction
    (pp. 3-10)

    Darwin’s views of the role of theory in evolutionary biology will warm any theorist’s heart: “let theory guide your observations”; “all observation must be for or against some view if it is to be of any service!” (Gruber and Barrett 1974). In common with physical scientists, Darwin saw theoretical ideas as providing the plans that give shape and coherence to facts and observations that otherwise would lie around like a pile of bricks at a building site.

    Ecological theory can, of course, take many forms, many of which are not at all mathematical. Darwin was the most influential ecological and...

    • Chapter 1 Plant Physiological Ecology: A Theoretician’s Perspective
      (pp. 11-24)

      The central issues of plant physiological ecology concern the effects of environment on individual plant growth, survival, and reproduction. In this regard, physiology is viewed as the mechanism through which the joint effects of heredity and environment are coupled to determine the growth form and reproductive success of an individual (Kramer 1948). My goal here is to provide a very brief review of the major questions that the field addresses, with emphasis on the use of theory; give a few examples of how theory has contributed new perspectives; point out some directions I feel are as yet relatively unexplored; and,...

    • Chapter 2 Individual Behavior and the Procurement of Essential Resources
      (pp. 25-38)

      The relationship between behavior and the availability of resources is a central part of behavioral ecology. Accordingly, many questions asked by behavioral ecologists deal with either the procurement or allocation of resources. In the case of procurement, the resources in question may be food, mates, space, or refuges and the individual in question must decide how to acquire them. On the other hand, questions concerning sex ratio, life-history strategy, and helping behavior deal with the allocation of resources such as nutrients, energy, and time that are already at the disposal of the individual in question. In this paper, I discuss...

    • Chapter 3 Discussion: From Individuals to Populations
      (pp. 39-53)
      M.A.R. KOEHL

      Processes operating at the level of individual organisms can determine the properties of populations, communities, and ecosystems. Theoretical studies can play an important role in advancing our understanding of the connection between organismal-level performance and patterns at the ecological level. In this paper I will first report our discussion of approaches to the area, including the roles of mechanistic versus phenomenological models, the interplay of theory and empiricism, and the usefulness of simple models and microcosm studies in understanding a complex world. I will then present a brief summary of examples of organismal-level analyses that have contributed to our understanding...

    • Chapter 4 Plant Population Dynamic Theory
      (pp. 54-67)

      One of the principal factors impeding the further integration of theoretical and empirical ecology is the difficulty of performing density manipulation experiments in the field. These experiments are the most direct way to calibrate and assess the simple density-dependent models that underpin much of population dynamic theory.

      Because plants are sedentary and typically lack a widely dispersive juvenile phase, it is straightforward to manipulate densities of internally recruiting plant populations. Such experiments have long demonstrated the importance of density-dependent interactions in plant communities and have led to a rich quantitative literature explaining the effects of competition on plant performance (reviews...

    • Chapter 5 Renewing the Dialogue between Theory and Experiments in Population Ecology
      (pp. 68-88)

      Theoretical population ecology has never been more vigorous. We have models for age-structured populations (Hastings 1986; Nisbet and Gurney 1986), stochastic environments (Chesson 1985), spatial heterogeneity (Levin 1978), and just about every type of species interaction imaginable (see, e.g., Edelstein-Keshet 1986; Addicott 1981; Pacala 1986). Not only is theory tackling the complexity and diversity of nature, but more and more models are being phrased in mechanistic terms (e.g., Tilman 1977,1982). Although robust general predictions seem out of the question, models are generating numerous hypotheses and insights regarding particular classes of species interactions.

      However, the current glories of theoretical population biology...

    • Chapter 6 Discussion: Population Dynamics and Species Interactions
      (pp. 89-100)

      Ecology is the scientific discipline that attempts to determine the causes of patterns in the distribution, abundance, and dynamics of the earth’s biota. The earth’s ecosystems are complex. In any given habitat, there are tens to hundreds or even thousands of different species. These influence each other both through direct pairwise interactions and through indirect interactions mediated by intermediate species, processes, or substances (Levine 1976; Holt 1977; Vandemeer 1980; Schaffer 1981). Because it is impractical, if not impossible, to observe all the potential interactions among all species and processes, ecological research involves the simplifying assumption that much of the complexity...

    • Chapter 7 Blending Ecology and Genetics: Progress toward a Unified Population Biology
      (pp. 101-124)

      The first step in examining the interplay of theoretical and empirical investigations in population biology is to bring the goal of these investigations into focus. That goal is to understand the genetic and phenotypic diversity within and among populations in terms of the microevolutionary forces that regulate that diversity. Those forces are functions ultimately of the numbers of individuals, the ecological factors that impose risks of mortality on those individuals and constrain their reproductive abilities, and the temporal and spatial patterns of population dynamics. Investigations in population biology revolve around the attempt to understand the joint dynamics of numbers of...

    • Chapter 8 Fossils, Macroevolution, and Theoretical Ecology
      (pp. 125-134)

      Paleobiology generates theory, and it also contributes information that must constrain theoretical advances in neontology. The fossil record provides the only documentation of the long-term evolution of species and of evolution above the species level. Although this record as a whole is highly incomplete, in places it is of high enough quality to resolve important evolutionary issues. To employ fossils fruitfully in addressing particular problems, we must single out appropriate segments of the record and use their data judiciously.

      Certainly the most important paleobiological issue now impinging on theoretical ecology is the controversy surrounding the punctuational model of evolution (Eldredge...

    • Chapter 9 Discussion: Ecology and Evolution
      (pp. 135-139)

      The two papers that introduce the interaction between evolutionary and ecological theory do so on vastly different time scales. Stanley’s paleobiological discussion presumes that morphological change exhibited in the fossil record is, for most of the time, extremely slow. Those events characterized by him as speciation are extreme discontinuities of stasis. The time scale here involves millions of generations. Travis and Mueller, on the other hand, address data and theory relevant to evolution within species and, mostly, within populations. The interaction between ecology and evolution is broached entirely differently in the two papers. In Stanley’s, the questions are: (1) Can...

    • Chapter 10 Perspectives in Hierarchy and Scale
      (pp. 140-156)
      R. V. O’NEILL

      The past two decades have seen a rapid change in the scale of ecological problems. In 1969, the National Environmental Policy Act required ecological assessment of impacts on surrounding ecosystems. From this local perspective we have moved to landscapes ecology, to the continental effects of acid precipitation, and to problems of nuclear winter, global carbon cycling, and climate change. The problems demand that we accelerate our ability to translate small-scale ecological principles to higher levels.

      It is fortunate that the demand for answers at higher levels has been accompanied by the development of new tools for the investigation of scale....

    • Chapter 11 Physical and Biological Scales of Variability in Lakes, Estuaries, and the Coastal Ocean
      (pp. 157-176)

      What is meant by “scale”? Why is it an important concept in ecology? Why does scale play a particularly prominent role when one speaks of “coupling”? Can one make nontrivial, general statements, if phrased in terms of scale alone, that apply to several seemingly different systems? Can other generalizations that highlight “scale” and “coupling” help us understand why some ecological systems differ so greatly from others? I shall address aspects of these questions here, with particular emphasis on results from lakes, estuaries, and the coastal ocean. I begin with some elementary notions, then review how scale considerations enter the coupling...

    • Chapter 12 Discussion: Scale and Coupling in Ecological Systems
      (pp. 177-180)

      The first discussion on hierarchies at the conference focused on two questions: (1) What kinds of systems are hierarchies? and (2) Are they the basis for theories or rather for the ordering of concepts?

      The traditional hierarchy is the organism, patch, population, and community. This interacts with a second structure—a population or community, its food supply, and the predators within it. Several participants pointed out that in understanding these interactions, we cannot operate only at the level of the average population density; we must consider how the individual organism behaves when feeding and when avoiding predators. Especially we need...

    • Chapter 13 Food Webs and Community Structure
      (pp. 181-202)

      A central problem of biology is to devise helpful concepts (e.g., genes) and tested quantitative models (e.g., Mendel’s laws) to describe, explain, and predict biological variation. The problem of characterizing variation arises in different guises in population genetics (genetic variation), demography (variation by age, sex, location, etc.), epidemiology (variation by risk factors and disease status), and ecology (variation in species composition and interactions in communities). In each field, there is variation over time, in space, and among units of observation (individuals, populations, or comparable habitats).

      This paper reviews some recent efforts to describe, explain, and predict variation in the food...

    • Chapter 14 The Structure and Assembly of Communities
      (pp. 203-226)

      The central question of community ecology was posed decades ago: Do the populations at a site consist of all those that happened to arrive there, or of only a special subset—those with properties allowing their coexistence? Elton (1933) wrote: “In any fairly limited area only a fraction of the forms that could theoretically do so actually form a community at any one time. . . . The animal community really is an organized community in that it apparently has ‘limited membership.’ ” Alternatively, Gleason (1926) wrote that “the vegetation of an area is merely the resultant of two factors,...

    • Chapter 15 Discussion: Structure and Assembly of Communities
      (pp. 227-241)

      The purpose of this chapter is threefold: (1) to provide a general overview of the relations between theoretical and empirical ecology at the community level; (2) to reflect the tenor of the discussion in the Community Ecology section of the Asilomar conference; and (3) to attempt to identify, from my own perspective, some of the concerns of empirical ecologists for what theory is relevant, necessary, and sufficient, and for what topics a theoretical basis is still lacking but necessary. I use as source material the papers by J. Roughgarden and J. Cohen (chapters 13 and 14) as well as transcripts...

    • Chapter 16 Challenges in the Development of a Theory of Community and Ecosystem Structure and Function
      (pp. 242-255)

      The impetus for improved mathematical approaches to the study of the structure and function of ecosystems has its foundations both in basic and in applied research. In the United States, the importance of such investigations is reflected in the research priorities of federal agencies as diverse as the National Science Foundation (NSF), Department of Energy (DOE), Environmental Protection Agency (EPA), and National Oceanic and Atmospheric Administration (NOAA). The funding by NSF of the International Biological Program (IBP) was in recognition of these needs, and those efforts were paralleled by the even earlier commitment by the Atomic Energy Commission (AEC), the...

    • Chapter 17 Simulators as Models of Forest Dynamics
      (pp. 256-267)

      The diversity of modeling approaches in ecology can be conveniently partioned into two brand categories that we shall refer to as analytical models and simulators. By “analytical models” we mean mathematical models that can potentially be solved in closed form. These include differential equations, Markov models, and other such formulations. Most current analytical models of forest dynamics are either based on systems of linear equations or solved by linear expansion about points of interest. In contrast, “simulators” typically incorporate richer biological detail, including explicit nonlinearities, at the expense of mathematical intractability. They are generally solved by computer using Monte Carlo...

    • Chapter 18 Discussion: Ecosystem Structure and Function
      (pp. 268-274)

      Traditionally, ecosystem studies have considered the movement of energy and materials through arbitrarily defined units of biotic communities. While Tansley (1935) first offered the ecosystem concept to ecology, the traditional focus was perhaps best enunciated by Evans (1956), who suggested that an ecosystem ecologist studies “the circulation, transformation, and accumulation of energy and matter through the medium of living things and their activities.” Early examples of ecosystem analysis are best found in the literature of aquatic ecology, where the classic paper by Lindeman (1942) remains a benchmark in the understanding of energy flow through connected trophic levels. Progress in ecosystem...

    • Chapter 19 Bioeconomics
      (pp. 275-286)

      The word “bioeconomics” (sometimes “bionomics”) has been employed with two quite different meanings. First, “bioeconomics” has been used to describe the ways in which biological organisms allocate resources to optimize reproductive success. For example, ther-Kselection dichotomy has been characterized as a bionomic question (Southwood 1981).

      In this article I employ the word “bioeconomics” to refer instead to the gamut of interactions between biological systems on the one hand and human economic systems on the other. It is manifestly obvious that biological resources are crucial to man’s welfare—we depend on them exclusively for food, and to a major...

    • Chapter 20 Theoretical Issues in Conservation Biology
      (pp. 287-305)

      Fragmentation has a qualitative effect on a population’s probability of extinction. A fragment will likely be different from the continuous habitat of which it earlier was a part. Edge effects (Wilcove, McLellan, and Dobson 1986; Lovejoy et al. 1986) are an important consideration. An edge may allow the penetration of biotic factors that would not otherwise be felt within the system. Predators from the surrounding habitat are one clear example (Wilcove, McLellan, and Dobson 1986). There may even be abiotic changes in the edge zone. Lovejoy et al. (1986) found that changes in light penetration, wind, and humidity extend hundreds...

    • Chapter 21 Discussion: Ecology and Resource Management—Is Ecological Theory Any Good in Practice?
      (pp. 306-318)

      One is tempted to answer the question posed in the title of this essay with a simple “yes”—ecological theory can help in solving many of the most important problems facing humanity. After all, the most important ecological theory was put forth 130 years ago by Charles Darwin, explaining, among other things, the crucial observation that antibiotics and pesticides become less effective with continued use, to say nothing of putting all of biomedical science into a coherent whole rather than leaving a mishmash of unconnected phenomena.

      But Darwin’s theory is so pervasive in its application that it is taken for...

    • Chapter 22 The Population Biology of Host-Parasite and Host-Parasitoid Associations
      (pp. 319-347)

      In the study of any population of plants or animals, two central questions are: What is the basic reproductive rate,R₀(the number of surviving female offspring that each female could on average produce in the absence of external constraints), and what particular mixture of density-independent and density-dependent effects acts to keep the long-term average of the effective reproductive rate,R,around unity for most populations? The first question is vividly illustrated by the Smithsonian Museum of Natural History’s exhibit on evolution, in which a kitchen swarms with all the cockroaches one female would produce if all survived. Our ignorance...

    • Chapter 23 Discussion: Ecology of Pests and Pathogens
      (pp. 348-362)

      This chapter records the discussion that took place at the conference on the general theme of the ecology of pests and pathogens. The aim is to survey current developments and, more importantly, interesting directions for future work both on fundamental aspects of the population biology of associations between hosts and pathogens, parasites or predators, and on applications of this work to the control of pests and diseases. I also make an attempt, where appropriate, to indicate areas of research that might benefit from adopting methods or ideas that have proved their worth in other contexts.

      The chapter begins with a...

  11. Appendix. Ecological Theory: A List of Books
    (pp. 363-366)
  12. List of Participants
    (pp. 367-370)
  13. Author Index
    (pp. 371-382)
  14. Subject Index
    (pp. 383-394)