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Animal life, now and over the past half billion years, is incredibly diverse. Describing and understanding the evolution of this diversity of body plans — from vertebrates such as humans and fish to the numerous invertebrate groups including sponges, insects, molluscs, and the many groups of worms — is a major goal of evolutionary biology. This book adopts a modern, integrated approach to describe how current molecular genetic techniques and disciplines as diverse as palaeontology, embryology, and genomics have been combined, resulting in a dramatic renaissance in the study of animal evolution. The last decade has seen growing interest in evolutionary biology fuelled by a wealth of data from molecular biology. Modern phylogenies integrating evidence from molecules, embryological data, and morphology of living and fossil taxa provide a wide consensus of the major branching patterns of the tree of life; moreover, the links between phenotype and genotype are increasingly well understood. This has resulted in a reliable tree of relationships that has been widely accepted and has spawned numerous new and exciting questions that require a reassessment of the origins and radiation of animal life. The focus of this volume is at the level of major animal groups, the morphological innovations that define them, and the mechanisms of change to their embryology that have resulted in their evolution. Current research themes and future prospects are highlighted including phylogeny reconstruction, comparative developmental biology, the value of different sources of data and the importance of fossils, homology assessment, character evolution, phylogeny of major groups of animals, and genome evolution. These topics are integrated in the light of a 'new animal phylogeny', to provide fresh insights into the patterns and processes of animal evolution.

The ever‐increasing knowledge of whole genome sequences is unveiling a variety of new structures and mechanisms that impinge on current evolutionary theory. The origin of species, the evolution of form and the evolutionary impact of transposable elements are just a few of the many processes that have been revolutionized by ongoing genome studies. These novelties are examined in this book in relation to their significance for evolution, emphasizing their human relevance. For example, the small genomic differences between humans and chimps challenges our understanding of what makes us humans in terms of genetic differences. Certainly, neither the increase in number of genes nor, probably, the changes in coding sequences are the key evolutionary differences that define our humanity. Most probably the relevant steps towards the evolution of higher forms, humans among them, have arisen in regulatory and assembling processes that decide when, where, and in which combination the already existing genetic blocks operate. These are just a few glimpses of these controversial issues that this book examines in the context of Darwinian evolution. Recently this debate has centred on arguments extracted from genomic and molecular information that have been intended to ‘deconstruct’ the Darwinian Theory. The purpose of this book is to show that whilst genome dynamism is providing new, and previously unanticipated, sources of variability, there is no reason to dismiss the role of natural selection as the leading mechanism that sorts out the adaptive potentialities. This book provides many examples to justify the argument to ‘reconstruct’, rather than to ‘deconstruct’, the Darwinian Theory.

Clinicians and scientists are increasingly recognising the importance of an evolutionary perspective in studying the aetiology, prevention, and treatment of human disease; the growing prominence of genetics in medicine is further adding to the interest in evolutionary medicine. In spite of this, too few medical students or residents study evolution. This book builds a compelling case for integrating evolutionary biology into undergraduate and postgraduate medical education, as well as its intrinsic value to medicine. Chapter by chapter, the authors – experts in anthropology, biology, ecology, physiology, public health, and various disciplines of medicine – present the rationale for clinically-relevant evolutionary thinking. They achieve this within the broader context of medicine but through the focused lens of maternal and child health, with an emphasis on female reproduction and the early-life biochemical, immunological, and microbial responses influenced by evolution. The tightly woven and accessible narrative illustrates how a medical education that considers evolved traits can deepen our understanding of the complexities of the human body, variability in health, susceptibility to disease, and ultimately help guide treatment, prevention, and public health policy. However, integrating evolutionary biology into medical education continues to face several roadblocks. The medical curriculum is already replete with complex subjects and a long period of training. The addition of an evolutionary perspective to this curriculum would certainly seem daunting, and many medical educators express concern over potential controversy if evolution is introduced into the curriculum of their schools. Medical education urgently needs strategies and teaching aids to lower the barriers to incorporating evolution into medical training. In summary, this call to arms makes a strong case for incorporating evolutionary thinking early in medical training to help guide the types of critical questions physicians ask, or should be asking. It will be of relevance and use to evolutionary biologists, physicians, medical students, and biomedical research scientists.

This book surveys the momentous morphological change in plant evolution that created the terrestrial biosphere as we know it today. It takes as its premise that the study of plant evolution at its grandest is the study of how mutations in genes have changed the way the planet functions. The evolution of the leaf, for instance, change terrestrial carbon cycling and primary productivity, so changing the earth's atmosphere and the distribution of carbon. The book charts the rise to complexity of the three many organs systems of complex land plants, the axis or stem, the leaf, and the root. These organs system are surveyed morphologically in the light of empirical morphology, in which organ concepts are considered as hypotheses to be tested in a developmental, molecular, and phylogenetic framework. It also tackles the evolution of the seed (via heterospory and covering of the megasporangium) and the flower (by complex patterning of sporophylls and sterile phyllomes). All this is placed where possible in its molecular context, with the aim of demonstrating how evolving gene networks have given rise to increasing morphological complexity.

The biologically intimate, causally reciprocal relationship between organisms and their environments shapes individual adaptation, ecological communities, and selective evolution. The book synthesizes a wealth of new research findings to examine how environments influence phenotypic expression in individual organisms (ecological development or eco-devo) and how organisms in turn alter their environments (niche construction). A key argument is that ecological interactions as well as natural selection are shaped by these organism–environment effects. The book begins with a chapter on development, examining the regulatory roles of epigenetic and environmental factors to support a unified eco-devo approach based on the norm of reaction. Next, the foundational concepts of ecological niche and adaptation are reconsidered to build a framework for studying the organism–environment relationship. The third chapter provides an overview of environmental cues and regulatory mechanisms that lead to plastic eco-devo responses, presenting detailed case studies. Subsequent chapters explore how such phenotypic responses modify the environmental conditions that individual organisms experience, and how microorganisms, plants, and animals modify their external environments. Community-level consequences of both organismic effects on the environment and individual eco-devo responses (trait-mediated interactions) are then examined. In the final chapter, natural selection is discussed in light of organism–environment effects, including the environmental dependence of gene expression and genetic variance; epigenetic and cytoplasmically inherited environmental factors; and effects of organisms on their selective environments (eco-evolutionary feedbacks). A short epilogue proposes that focusing on the organism–environment relationship can lead to novel testable hypotheses, practical solutions, and insights into future adaptation.

The aim of this book is to shed light on one of the most fundamental processes of life in the various lineages of animals: respiration. It provides a certain background on the physiological side of respiration, but it clearly focuses on the morphological aspects. In general, the intention of this book is to illustrate the impressive diversity of respiratory faculties (form–function complexes) rather than serving as an encyclopaedic handbook. It takes the reader on a journey through the entire realm of animals and discusses the structures involved in gas exchange, how they work, and most importantly, how all of this may be connected on an evolutionary scale. Due to the common problem, namely oxygen uptake and carbon dioxide release, and the limited number of solutions, basically surface area, barrier thickness, and physical exchange model of the respiratory organ, it is not surprising that one finds a huge number of convergences. These include, for instance, the repeated origin of tubular tracheae among several lineages of arthropods, similar lung structures in snails and amphibians, and counter-current exchange gills in bivalves and fish. However, there are certain phylogenetic constraints evident and the respiratory faculty appears as a yet to be adequately exploited source of information for systematic considerations. The ultimate goal of this book is to stimulate further research in respiratory biology, because a huge number of questions remain to be tackled on all levels, ranging from molecular through functional to especially the evolutionary aspects.

Is it possible to explain and predict the development of living things? And is the formulation of theories helpful to achieve this aim? This volume offers an in-depth examination of the role of theories and theorization in developmental biology: does this field offer theories, and if so, in what sense of the word ‘theory’? Are theories useful in the everyday practice of developmental biologists? Should developmental biologists seek to construct more theories and perhaps even a unifying theoretical framework for their field? Key issues are at stake in this debate, including the very definition and delineation of ‘development’, as well as the scientific status of developmental biology as a field offering descriptions, explanations, and predictions of developmental processes. Written by leading developmental biologists, philosophers of biology, and students of evo-devo, this volume analyses a wealth of approaches to concepts, models, and theories of development, such as gene regulatory networks, accounts based on systems biology and on physics of soft matter, the different articulations of evolution and development, and symbiont-induced development, as well as the widely discussed concepts of positional information and morphogenetic field, the idea of a ‘programme’ of development and its critiques, and the long-standing opposition between preformationist and epigenetic conceptions of development.