The three new chapters, 7, 8, and 12, written for this edition are intended to strengthen coverage of behavioral and evolutionary ecology. Chapter 7, "Social Relations," concludes Section II of the book and introduces behavioral ecology. This chapter extends the discussion of the ecology of individuals in Section II to interactions between individuals within the social environment. Chapter 7 focuses on mate choice and sexual selection and the evolution of sociality. Case histories demonstrating mating ecology are drawn from studies of guppies, scorpionflies, and wild radish. The discussion of sociality draws from extensive studies on cooperation among woodhoopoes and African lions, emphasizing the concepts of inclusive fitness and kin selection. The Applications and Tools section continues the discussion of sociality through a comparison of eusocial species as a way of introducing the comparative method. Section III is introduced by a new Chapter 8 titled "Population Genetics and Natural Selection." Chapter 8 presents the conceptual basis for evolutionary ecology through case histories concerning genetic and phenotypic variation in populations, the Hardy-Weinberg equilibrium model, changes in the genetic structure of populations due to random processes, and natural selection. The case histories, as in all parts of the book, attempt to include a wide variety of plant and animal studies and to balance vertebrate with invertebrate animal coverage. The coverage also emphasizes a historical perspective that spans the beginnings of evolutionary ecology through very recent work, employing modern tools and perspectives. Chapter 12, titled "Life Histories," is the third new chapter. This chapter concludes the section on population ecology and provides additional evolutionary perspective. The case histories in chapter 12 begin with a discussion of the trade off between offspring size and number, further developing the "principle of allocation" introduced in chapter 6, while the second set of case histories concerns the relationship between adult survival and age at first reproduction. The case histories in chapter 12 conclude with a classification of life histories, beginning with r versus K selection and ending with a classification of life histories that proposes opportunistic (r), equilibrium (K), and periodic life histories as alternative evolutionary trajectories. Again, the chapter develops parallel discussions of plants and animals throughout. It ends with an applications and tools section showing how knowledge of plant life histories is being used to restore riparian forests in western North America. |
2002 McGraw-Hill Higher Education