Properties of populations include age and spatial distribution, both of which emerge from actions and properties of individuals and can affect population dynamics, the changes in populations and metapopulations over time and space. The age structure of a population is described and analyzed to determine how it affects the growth of a population. The various aspects of spatial structure of populations, which also arise from characteristics and behaviors of individuals, are examined and used to develop the concept of a metapopulation. Finally, this book discusses how individuals perform...

This book will synthesize the concepts of selection against individuals in response to environmental change to illustrate how selection against individuals results in homeostasis at the population level. For instance, selection against the light phenotype of the peppered moth during the early part of the industrial revolution led to an increase of the dark phenotype, which was better camouflaged against the soot that accumulated on tree bark as a result of burning coal. Populations are shown to be regulated by feedback mechanisms, several of which are discussed here. Populations are regulated...

Organisms maintain homeostasis in a variety of ways. In the first part of this book, mammals are shown to regulate their body temperatures through homeostatic mechanisms. The data from thermoregulation experiments that demonstrated the role of neurons in body temperature homeostasis are examined. The second part of this book discusses how organisms allocate the limited energy that is available to them for survival, growth, or reproduction. Excess energy in individuals can translate to growth of populations: if enough remains after survival and growth, it can be allocated to reproduction....

Three of the four major mechanisms of evolution, natural selection, genetic drift, and gene flow are examined. There are 5 tenets of natural selection that influence individual organisms: Individuals within populations are variable, that variation is heritable, organisms differ in their ability to survive and reproduce, more individuals are produced in a generation than can survive, and survival & reproduction of those variable individuals are non-random. Organisms respond evolutionarily to changes in their environment and other selection pressures, including global climate change. The...

This book identifies the commonalities between communication within a species and communication between species. Behavior and exchange of non-heritable information occurs between individuals of different species, in animals and plants, in order to exploit other species and compete for resources. Several examples of adaptations of one species to exploit the information passed between individuals of another species are given. This book describes how animals make decisions while gathering information and resources, selecting habitat, and interacting with potential competitors. Plants grow in...

Pairwise and diffuse coevolution are defined, with examples that include mutualisms and predator-prey interactions. In any example of coevolution, the costs and benefits to both species involved in the interaction must be assessed in order to understand evolution of the interaction. Models to explain coral bleaching are examined in the context of a coevolutionary mutualism, as are the implications for the possible extinction of coral reefs. Data are examined in order to determine which model is best supported. Other examples of how evolution affects interactions and communities of organisms...

This book describes how evolutionary history is studied using several well-known examples and also using evolutionary trees. Evolutionary trees are analyzed and used to explain adaptive radiations of orchids and the diversification of bats over geologic time. Evolutionary trees and genetic evidence is used to infer when and from what ancestors terrestrial plants evolved and invaded land. Specific adaptations of early land plants led to the evolution of terrestrial plants and their success on land. Evidence about the ancestors and habitats of humans is used to infer and analyze the evolution...

This book begins by describing what an individual organism is, comparing preconceptions of the individual to non-standard ways of thinking about individuals. Variation in what individuals are is described, using giant fungi, clonal trees and honey bee hives as examples. Individuals are thus shown to be emergent properties. Other emergent properties of individuals are also described. Classic experiments that elucidated the source of emotions in humans and other mammals are described. Emotions arise from the actions of the nervous and endocrine system and often include a variety of signals...

Food webs, energy flow, indirect effects, and nutrient cycling are described as properties that emerge in ecological systems. Several of these properties are shown in this book to result from indirect effects and interactions between species and abiotic components of ecological systems. For instance, top predators affect organisms with which they do not directly interact, including plants and non-prey animals. In some other interactions, including competition, the nonliving components of ecological systems (the abiota) can alter the outcome of a biotic interaction. A limiting resource often...

Several genetic and pathogenic diseases are described to illustrate how diseases can and do disrupt normal molecular and cellular functions, and how those disruptions affect entire organisms. In the case of genetic diseases, how they arise and are maintained in populations is discussed. In the case of pathogenic and parasitic organisms, understanding their complex life cycles and their modes of transmission is critical to understanding their effects on individuals and how disease outbreaks occur in ecological systems. Communication between the pathogen and the host organism occurs in the...