The Adaptive Landscape In Evolutionary Biology

The 'Adaptive Landscape' has been a central concept in population genetics and evolutionary biology since this powerful metaphor was first formulated by Sewall Wright in 1932. Eighty years later, it has become a central framework in evolutionary quantitative genetics, selection studies in natural populations, and in studies of ecological speciation and adaptive radiations. Recently, the simple concept of adaptive landscapes in two dimensions (genes or traits) has been criticized and several new and more sophisticated versions of the original adaptive landscape evolutionary model have been developed in response. No published volume has yet critically discussed the past, present state, and future prospect of the adaptive landscape in evolutionary biology. This volume brings together prominent historians of science, philosophers, ecologists, and evolutionary biologists, with the aim of discussing the state of the art of the Adaptive Landscape from several different perspectives.

The metaphor of the adaptive landscape - that evolution via the process of natural selection can be visualized as a journey across adaptive hills and valleys, mountains and ravines - permeates both evolutionary biology and the philosophy of science. The focus of this 2006 book is to demonstrate to the reader that the adaptive landscape concept can be put into actual analytical practice through the usage of theoretical morphospaces - geometric spaces of both existent and non-existent biological form - and to demonstrate the power of the adaptive landscape concept in understanding the process of evolution. The adaptive landscape concept further allows us to take a spatial approach to the concepts of natural selection, evolutionary constraint and evolutionary development. For that reason, this book relies heavily on spatial graphics to convey the concepts developed within these pages, and less so on formal mathematics.

Pillars of Evolution provides a fresh and provocative perspective on adaptive evolution. Readers new to the study of evolution will find a refreshing new insight that establishes evolutionary biology as a rigorous and predictive science, whilst practicing biologists will discover a provocative book that challenges traditional approaches. The book begins by leading readers through the mechanics of heredity, reproduction, movement, survival, and development. With that framework in place, it then explores the numerous ways that traits emerge from the interactions between genetics, development, and the environment. The key message is that adaptive changes in traits (and their underlying allelic frequencies) evolve through the traits' functions and their connection with fitness. The complex mappings from genes-to-traits-to-fitness are characterized in the structure of evolution. A single "structure matrix" describes why individuals vary in the values of adaptive traits, their ability to perform the function of those traits, and in the fitness they accrue. Fitness depends on how organisms interact with and perceive their environment in time and space. These relationships are made explicit in spatial, temporal, and organizational scale that also sets the stage for the crucially important role that ecology always plays in evolution. The ecological hallmarks of density- and frequency-dependent interactions allow the authors to explore new and exciting insights into evolution's dynamics. The theories and principles are then brought together in a final synthesis on adaptation. The book's unique approach unites genetic, development, and environmental influences into a single comprehensive treatment of the eco-evolutionary process.

Modern evolutionary theory, also known as the modern synthesis, has lately become the subject of much criticism - and yet, David Merrell observes, its critics all too often display an incomplete understanding of the theory and its provenance. In this book, Merrell provides a lucid exposition and critique of the modern synthetic theory of evolution - its history, its present difficulties, and its future - from the perspective of ecological genetics. Based on observational and experimental data, in natural populations of plants and animals studied in the field and in the laboratory, this perspective unravels the hidden and often poorly founded assumptions underlying some of the more troublesome controversies in evolutionary biology today. Evolution, Merrell suggests, occurs through many mechanisms, and this pluralism informs his approach to evolutionary problems, which usually have been discussed in extreme, generally unjustifiable dichotomies. Thus, although much of evolution, in accordance with the Darwinian model, is slow and gradual, Merrell makes the case for rapid, even instantaneous large change as well. He also demonstrates the importance of genes of major effect, especially dominant genes, in bringing about evolutionary change, contrary to the widely held belief that such change only results from the accumulation of numerous genes of small effect. Using these concepts, Merrell interprets the evolution of industrial melanism, DDT resistance, and mimicry. In the treatment of the nature and origin of species, Merrell proposes an "adaptive seascape" to replace Sewall Wright's well-known "adaptive landscape" as a metaphor for the adaptive surface, where the physical and biologicalenvironment is constantly changing. Expert yet accessible, Merrell's depiction of this seascape will clarify the state of evolutionary theory both for specialists and for general readers with an interest in science.

Over the last two decades, research into epistasis has seen explosive growth and has moved the focus of research in evolutionary genetics from a traditional additive approach. We now know the effects of genes are rarely independent, and to reach a fuller understanding of the process of evolution we need to look at gene interactions as well as gene-environment interactions. This book is an overview of non-additive evolutionary genetics, integrating all work to date on all levels of evolutionary investigation of the importance of epistasis in the evolutionary process in general. It includes a historical perspective on this emerging field, in-depth discussion of terminology, discussions of the effects of epistasis at several different levels of biological organization and combinations of theoretical and experimental approaches to analysis.

The last few years have seen a number of new books on evolutionary biology. However most of these are either large or specialized. This is an attempt to produce a thin, general version for undergraduate use. Thinness, of course, demands selectivity, and the aim has been to concentrate on the principles of the subject rather than on the details-principles, that is, of both theory and practice. Thinness also sometimes means that a certain level of knowledge is assumed in the readership, but I hope that this is not the case here, and my intention has certainly been to produce something that is as intelligible to the uninitiated as it is to the well-informed. As for the bibliography, I refer, where possible, to reviews rather than primary sources, so a citation should not be taken to imply any sort of precedence. In developing the theme, I have adopted a loosely historical approach, not only because I believe that this makes for more interesting reading but also because the subject, like the subject it addresses, has evolved under the critical eye of a selective process. Problems have been perceived, hypotheses have been formulated to explain them, facts have been amassed to test the hypotheses, more problems have been perceived, more hypotheses formu lated, and so on.

How the principles of biological innovation can help us overcome creative challenges in art, business, and science In Life Finds a Way, biologist Andreas Wagner reveals the deep symmetry between innovation in biological evolution and human cultural creativity. Rarely is either a linear climb to perfection--instead, "progress" is typically marked by a sequence of peaks, plateaus, and pitfalls. For instance, in Picasso's forty-some iterations of Guernica, we see the same combination of small steps, incessant reshuffling, and large, almost reckless, leaps that characterize the way evolution transformed a dinosaur's grasping claw into a condor's soaring wing. By understanding these principles, we can also better realize our own creative potential to find new solutions to adversity. Ultimately, Life Finds a Way offers a new framework for the nature of creativity, enabling us to better adapt, grow, and change in art, business, or science--that is, in life.

Samir Okasha offers a philosophical perspective on evolutionary biology in Agents and Goals in Evolution. His focus is on "agential thinking", which is a mode of thought commonly employed in evolutionary biology. The paradigm case of agential thinking involves treating an evolved organism as if it were an agent pursuing a goal, such as survival or reproduction, and treating its phenotypic traits as strategies for achieving that goal, or furthering its biological interests. Agential thinking involves deliberately transposing a set of concepts - goals, interests, strategies - from rational human agents to the biological world more generally. Okasha's enquiry begins by asking whether this is justified. Is agential thinking mere anthropomorphism, or does it play a genuine intellectual role in the science? This central question leads Okasha to a series of further questions. How do we identify the "goal" that evolved organisms will behave as if they are trying to achieve? Can agential thinking ever be applied to groups or genes, rather than to individual organisms? And how does agential thinking relate to the controversies over fitness-maximization in evolutionary biology? In the final third of the book, Okasha examines the relation between the adaptive and the rational. If organisms can validly be treated as agent-like, for the purposes of evolutionary analysis, should we expect that their evolved behaviour will correspond to the behaviour of rational agents as codified in the theory of rational choice? If so, does this mean that the fitness-maximizing paradigm of the evolutionary biologist can be mapped directly to the utility-maximizing paradigm of the rational choice theorist? Okasha explores these questions using an inter-disciplinary methodology that draws on philosophy of science, evolutionary biology and economics.