A major synthesis of homology, written by a top researcher in the field Homology—a similar trait shared by different species and derived from common ancestry, such as a seal's fin and a bird’s wing—is one of the most fundamental yet challenging concepts in evolutionary biology. This groundbreaking book provides the first mechanistically based theory of what homology is and how it arises in evolution. Günter Wagner, one of the preeminent researchers in the field, argues that homology, or character identity, can be explained through the historical continuity of character identity networks—that is, the gene regulatory networks that enable differential gene expression. He shows how character identity is independent of the form and function of the character itself because the same network can activate different effector genes and thus control the development of different shapes, sizes, and qualities of the character. Demonstrating how this theoretical model can provide a foundation for understanding the evolutionary origin of novel characters, Wagner applies it to the origin and evolution of specific systems, such as cell types; skin, hair, and feathers; limbs and digits; and flowers. The first major synthesis of homology to be published in decades, Homology, Genes, and Evolutionary Innovation reveals how a mechanistically based theory can serve as a unifying concept for any branch of science concerned with the structure and development of organisms, and how it can help explain major transitions in evolution and broad patterns of biological diversity.

The application of homology varies depending on the data being examined. This volume represents a state-of-the-art treatment of the different applications of this unifying concept. Chapters deal with homology on all levels, from molecules to behavior, and are authored by leading contributors to systematics, natural history, and evolutionary, developmental, and comparative biology. This paperback reprint of the original hardbound edition continues to commemorate the 150th anniversary of Sir Richard Owen's seminal paper distinguishing homology from analogy. Commemoration of the 150th anniversary of Sir Richard Owen's seminal paper distinguishing homology from analogy Contributors who are renowned leaders in comparative biology Coverage that is both comprehensive and interdisciplinary

A philosophical exploration of the interdisciplinary nature of evo-devo and its concepts, including conserved mechanisms, deep homology, and evolutionary novelty. This title is also available as Open Access on Cambridge Core.

'Homology' as a concept became increasingly elusive during the course of the 20th century. The central debates and controversies concern both fundamental definitions and the nature of the criteria by which homology is judged. Attempts to move away from comparative morphology to ideas based on developmental pathways have tended to founder on the fact that developmental pathways evolve and that similar cells or tissues or structures in animals will often have different developmental origins. The use of information about conserved molecules in seemingly conserved developmental processes has also proven controversial. In molecular biology, the use of the term 'homology' has given rise to more debate, although here the issue seems to involve primarily the criteria for assessing whether parts of genes are the same because of shared descent or for other reasons. The contributions to the book explore these topics systematically. There are chapters on the historical development of the concept of homology and its use in population studies. Other chapters deal with issues of homology in morphological and developmental studies, in behavioural studies, and especially in studies at the level of molecular genetics.

A new account of the central role developmental processes play in evolution A new scientific view of evolution is emerging—one that challenges and expands our understanding of how evolution works. Recent research demonstrates that organisms differ greatly in how effective they are at evolving. Whether and how each organism adapts and diversifies depends critically on the mechanistic details of how that organism operates—its development, physiology, and behavior. That is because the evolutionary process itself has evolved over time, and continues to evolve. The scientific understanding of evolution is evolving too, with groundbreaking new ways of explaining evolutionary change. In this book, a group of leading biologists draw on the latest findings in evolutionary genetics and evo-devo, as well as novel insights from studies of epigenetics, symbiosis, and inheritance, to examine the central role that developmental processes play in evolution. Written in an accessible style, and illustrated with fascinating examples of natural history, the book presents recent scientific discoveries that expand evolutionary biology beyond the classical view of gene transmission guided by natural selection. Without undermining the central importance of natural selection and other Darwinian foundations, new developmental insights indicate that all organisms possess their own characteristic sets of evolutionary mechanisms. The authors argue that a consideration of developmental phenomena is needed for evolutionary biologists to generate better explanations for adaptation and biodiversity. This book provides a new vision of adaptive evolution.

This new edition captures the advances made in the field of evolutionary systems biology since the publication of the first edition. The first edition focused on laying the foundations of evolutionary systems biology as an interdisciplinary field, where a way of thinking and asking questions is combined with a wide variety of tools, both experimental and theoretical/computational. Since publication of the first edition, evolutionary systems biology is now a well-known term describing this growing field. The new edition provides an overview of the current status and future developments of this interdisciplinary field. Chapters highlight several key achievements from the last decade and outline exciting new developments, including an understanding of the interplay between complexity and predictability in evolutionary systems, new viewpoints and methods to study organisms in evolving populations at the level of the genome, gene regulatory network, and metabolic network, and better analysis and modeling techniques that will open new avenues of scientific inquiry.

Darwin’s nineteenth-century writings laid the foundations for modern studies of evolution, and theoretical developments in the mid-twentieth century fostered the Modern Synthesis. Since that time, a great deal of new biological knowledge has been generated, including details of the genetic code, lateral gene transfer, and developmental constraints. Our improved understanding of these and many other phenomena have been working their way into evolutionary theory, changing it and improving its correspondence with evolution in nature. And while the study of evolution is thriving both as a basic science to understand the world and in its applications in agriculture, medicine, and public health, the broad scope of evolution—operating across genes, whole organisms, clades, and ecosystems—presents a significant challenge for researchers seeking to integrate abundant new data and content into a general theory of evolution. This book gives us that framework and synthesis for the twenty-first century. The Theory of Evolution presents a series of chapters by experts seeking this integration by addressing the current state of affairs across numerous fields within evolutionary biology, ranging from biogeography to multilevel selection, speciation, and macroevolutionary theory. By presenting current syntheses of evolution’s theoretical foundations and their growth in light of new datasets and analyses, this collection will enhance future research and understanding.