The most important feature of the modern synthetic theory of evolution is its foundation upon a great variety of biological disciplines. -G. L. STEBBINS, 1968, p. 17 This book is written with the goal of presenting ecologically significant anal­ ogies between the biology of microorganisms and macroorganisms. I consider such parallels to be important for two reasons. First, they serve to emphasize that however diverse life may be, there are common themes at the ecological level (not to mention other levels). Second, research done with either microbes or macroorganisms has implications which transcend a particular field of study. Although both points may appear obvious, the fact remains that at­ tempts to forge a conceptual synthesiS are astonishingly meager. While unify­ ing concepts may not necessarily be strictly correct, they enable one to draw analogies across disciplines. New starting points are discovered as a conse­ quence, and new ways of looking at things emerge. The macroscopic organisms ('macroorganisms') include most represen­ tatives of the plant and animal kingdoms. I interpret the term 'microorganism' (microbe) literally to mean the small or microscopic forms of life, and I include in this category the bacteria, the protists (excluding the macroscopic green, brown, and red algae), and the fungi. Certain higher organisms, such as many of the nematodes, fall logically within this realm, but are not discussed at any length.

Table of Contents:
1 Introduction: Prospects for a Conceptual Synthesis.- 1.1 Differences and Similarities.- 1.2 A Framework for Comparison.- 1.3 What is an Individual?.- 1.4 Summary.- 1.5 Suggested Additional Reading.- 2 Genetic Variation.- 2.1 Introduction.- 2.2 Mechanisms.- 2.3 Sex and Meiotic Recombination.- 2.4 Somatic Variation and the Concept of the Genet.- 2.5 Summary.- 2.6 Suggested Additional Reading.- 3 Nutritional Mode.- 3.1 Introduction.- 3.2 What is a Resource?.- 3.3 Some Fundamental Resource Categories and Their Implications.- 3.4 Resource Acquisition.- 3.5 Summary.- 3.6 Suggested Additional Reading.- 4 Size.- 4.1 Introduction.- 4.2 Constraints on Natural Selection: Phylogenetic, Ontogenetic, and Allometric.- 4.3 Why Are There Macroorganisms?.- 4.4 On Seeing the World As an Elephant or a Mycoplasma.- 4.5 Some Correlates of Size.- 4.6 Some Ecological Consequences of Size.- 4.7 Size and Life History Theory.- 4.8 Summary.- 4.9 Suggested Additional Reading.- 5 Growth and Growth Form.- 5.1 Introduction.- 5.2 Unitary and Modular Organisms: An Overview.- 5.3 Fungi As Modular Organisms.- 5.4 Bacteria As Modular Organisms.- 5.5 Some Implications of Being Modular.- 5.6 Some Implications to Modular Organisms of Being Sessile.- 5.7 Form in the Natural World.- 5.8 Summary.- 5.9 Suggested Additional Reading.- 6 The Life Cycle.- 6.1 Introduction.- 6.2 Simple Versus Complex Life Cycles.- 6.3 Senescence.- 6.4 Summary.- 6.5 Suggested Additional Reading.- 7 The Environment.- 7.1 Introduction.- 7.2 The Environment and Organism Are Coupled.- 7.3 How Organisms Experience Environments.- 7.4 How Organisms Respond to Environments.- 7.5 Traffic Lights Regulate Progress Through the Life Cycle.- 7.6 Habitable Sites and the Evolution of Gene Flow.- 7.7 Summary.- 7.8 Suggested Additional Reading.- 8 Conclusion: Commonalities and Differences in Life Histories.- 8.1 Levels of Comparison.- 8.2 On Being a Macroorganism or a Microorganism.- 8.3 Natural Selection As the Common Denominator.- 8.4 Microbial Ecology and Macroecology Are Complementary.- 8.5 Summary.