The economy of nature / Robert E. Ricklefs

Incluye referencias bibliográficas

Throughout this textbook you will see a high value placed on three tenets of teaching introductory ecology: First, a solid grounding in natural history. The more we know about habitats and their resident organisms, the better we are able to generalize. Second, an appreciation of the organism as the funda¬mental unit of ecology. The structure and dynamics of populations, communities, and ecosystems express the activities of, and interactions among, the organisms they comprise. That a population of insects increases to out¬break proportions depends on the fecundity and survival of individuals in the population, and the fecundity and survival reflect, in turn, the interaction of the individual with resources, predators, and physical conditions of the environment. Similarly, the regeneration of nutrients within an ecosystem depends in large part on the activi¬ties of individual microorganisms that make waste prod¬ucts of their own feeding and metabolism available as resources to plants. Third, the central position of evolution ary thinking in the study of ecology. The qualities of all ecological sys¬tems express the evolutionary adaptations of their com¬ponent species. It is impossible to understand how eco¬logical systems develop, function, and respond to per-turbation without understanding the evolutionary dynamics of populations. I have therefore organized the book so that students are immediately introduced to the physical environment and the ways in which organisms adapt to their sur¬roundings in Chapters 1-4. The book then introduces the concept of the biome to illustrate the diversity of habitats on earth in Chapter 5. Chapters 6-8 discuss how energy and elements move among the different components of the biosphere, emphasizing the intercon-nectedness of life and the physical world. The book then treats processes at the level of the organism in Chapters 9-12: these chapters focus on adaptation and the fun¬damental trade-offs that organisms make.