Does natural selection act primarily on individual organisms, on groups, on genes, or on whole species? This book provides a comprehensive analysis of the debate in evolutionary biology over the levels of selection, focusing on conceptual, philosophical and foundational questions.

Does natural selection act primarily on individual organisms, on groups, on genes, or on whole species? This book provides a comprehensive analysis of the debate in evolutionary biology over the levels of selection, focusing on conceptual, philosophical and foundational questions.

Much of the evolutionary debate since Darwin has focused on the level at which natural selection occurs. Most biologists acknowledge multiple levels of selection—from the gene to the species. The debate about group selection, however, is the focus of Mark E. Borrello’s Evolutionary Restraints. Tracing the history of biological attempts to determine whether selection leads to the evolution of fitter groups, Borrello takes as his focus the British naturalist V. C. Wynne-Edwards, who proposed that animals could regulate their own populations and thus avoid overexploitation of their resources. By the mid-twentieth century, Wynne-Edwards became an advocate for group selection theory and led a debate that engaged the most significant evolutionary biologists of his time, including Ernst Mayr, G. C. Williams, and Richard Dawkins. This important dialogue bled out into broader conversations about population regulation, environmental crises, and the evolution of human social behavior. By examining a single facet in the long debate about evolution, Borrello provides powerful insight into an intellectual quandary that remains relevant and alive to this day.

Evolutionary biologists have recognised that natural selection operates for the good of lower-level units (the individual, the cell, even the gene) rather than the good of the group. In this volume, 12 scientists discuss why this should be the case.

Quantitative traits-be they morphological or physiological characters, aspects of behavior, or genome-level features such as the amount of RNA or protein expression for a specific gene-usually show considerable variation within and among populations. Quantitative genetics, also referred to as the genetics of complex traits, is the study of such characters and is based on mathematical models of evolution in which many genes influence the trait and in which non-genetic factors may also be important. Evolution and Selection of Quantitative Traits presents a holistic treatment of the subject, showing the interplay between theory and data with extensive discussions on statistical issues relating to the estimation of the biologically relevant parameters for these models. Quantitative genetics is viewed as the bridge between complex mathematical models of trait evolution and real-world data, and the authors have clearly framed their treatment as such. This is the second volume in a planned trilogy that summarizes the modern field of quantitative genetics, informed by empirical observations from wide-ranging fields (agriculture, evolution, ecology, and human biology) as well as population genetics, statistical theory, mathematical modeling, genetics, and genomics. Whilst volume 1 (1998) dealt with the genetics of such traits, the main focus of volume 2 is on their evolution, with a special emphasis on detecting selection (ranging from the use of genomic and historical data through to ecological field data) and examining its consequences.

This book provides fascinating insights into the development and genetics of evolutionary processes on the basis of animals living in the dark, such as the Astyanax cave fish. Biologically functionless traits show high variability, which results from neutral deleterious mutations no longer being eliminated by natural selection, which normally acts to preserve functional capability. These negative mutations accumulate until the traits they are responsible for become rudimentary or even lost. The random genetic basis of regressive evolution is in accordance with Nei’s Neutral Theory of Molecular Evolution, which applies to the molecular level. Such processes are particularly conspicuous in species living in constant darkness, where, for example in Astyanax, all traits depending on the exposure to light, like eyes, pigmentation, visually triggered aggressive behaviour, negative phototaxis, and several peripheral outcomes of circadian rhythmicity, are useless and diminish. In compensation constructive traits like taste, olfaction or the lateral line senses are improved by selection and do not show variability. Regressive and constructive traits inherit independently, proving that the rudimentation process is not driven by pleiotropic linkage between them. All these traits are subject to mosaic evolution and exhibit unproportional epistatic gene effects, which play an important role in evolutionary adaptation and improvement. Offering valuable evolutionary insights and supplemented by a wealth of illustrations, this book will appeal to evolutionary and developmental biologists alike.

This book embeds a novel evolutionary analysis of human group selection within a comprehensive overview of multilevel selection theory, a theory wherein evolution proceeds at the level of individual organisms and collectives, such as human families, tribes, states, and empires. Where previous works on the topic have variously supported multilevel selection with logic, theory, experimental data, or via review of the zoological literature; in this book the authors uniquely establish the validity of human group selection as a historical evolutionary process within a multilevel selection framework. Select portions of the historical record are examined from a multilevel selectionist perspective, such that clashing civilizations, decline and fall, law, custom, war, genocide, ostracism, banishment, and the like are viewed with the end of understanding their implications for internal cohesion, external defense, and population demography. In doing so, its authors advance the potential for further interdisciplinary study in fostering, for instance, the convergence of history and biology. This work will provide fresh insights not only for evolutionists but also for researchers working across the social sciences and humanities.