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38 of 41 people found the following review helpful:
5.0 out of 5 stars
A vital contribution to evolutionary theory, June 17, 2004
Developmental Plasticity and Evolution by Mary Jane West-Eberhard is an enormously important contribution to the modern (neo-Darwinian) theory of organic evolution. It presents a new way of understanding evolution. The book teaches us how environmental induction of purely phenotypic events, including learning, can drive evolution, and why a plastic and modular phenotype should replace mutation at the center stage of evolutionary thinking. It is my prediction that this book will precipitate a revolution in thought within biology, but that this will take time, as has any major new idea. Biologists in all fields related to evolution are encouraged to read this work.The book contains a masterful synthesis of biological facts and theories on the broadest of scales. It unites all disciplines within the biological sciences. It is not, however, merely an impressive review. Rather, it captures a vast collection of data and brilliantly organizes it around a set of fundamental principles about development and evolution from which the main messages of the book are crystallized. Whereas many of the concepts may be described as relatively simple, contemplating the connections between them, as well as their overall unification, becomes an infinitely more challenging and fascinating task. It is from this unification that West-Eberhard's coherent theory of development and evolution blossoms. Expertly guiding the reader from individual concepts to coherent theory, West-Eberhard captures our imagination at every twist and turn, and catapults the reader's mind in a myriad of unexpected directions. The writing is crisp, clean and captivating. The book is filled with exciting and highly felicitous examples from natural history, touching upon the lives of all kinds of organisms, from prions to elm trees and African elephants. The pages are richly textured with detailed examples, illustrations and various intellectual gems. One such delight is a discussion of Darwin's pangenesis theory and how it fails in light of sterile castes in the Hymenoptera. The book's main contribution to modern evolutionary biology is the revolutionary idea that environmental influences on development, not mutation, are the first order cause of design. This view is a fundamental alteration of emphasis in a field obsessed with genes, genetic drift and mass selection. The book places major emphasis on the importance of genetic accommodation, which occurs when developmentally-mediated changes in the phenotype are molded by quantitative genetic change. The hypothesis of genetic accommodation can be understood as beginning when the environment induces a phenotypic change. This change imposes a new selective regime onto pre-existing polygenic variation. In this way, we are encouraged to understand genes as "followers", as opposed to "leaders" in evolution. The variants can be inherited in subsequent generations if the environmental conditions inducing them are recurrent, and if there is genetic variation underlying the population in the developmental capacity to produce them. Natural selection will favor the spread of a particular environmentally-induced variant when it has positive effects on individual fitness. Although both mutation and environmental induction are considered important modes of initiation of new phenotypic variation, West-Eberhard's argument is that environmental induction is in fact more important. This thesis challenges the modern gene-centered view of evolution, and in so doing, drives the final nail in the coffin of the "one-gene-one-phenotype" illusion. The book encourages the view that a unified science of evolution can only be achieved with a thorough integration of development into evolutionary biology. To this end, Mary Jane West-Eberhard's treatise is an enormous success. By showing how environmentally influenced development contributes to the origin of novelty in all organisms, the book provides a key missing component of a modern evolutionary theory that biology has been lacking since Darwin. The book is essential reading for all graduate students, researchers and teachers of biology.
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