In this landmark work, the author team led by Dr. Sean Carroll presents the general principles of the genetic basis of morphological change through a synthesis of evolutionary biology with genetics and embryology. In this extensively revised second edition, the authors delve into the latest discoveries, incorporating new coverage of comparative genomics, molecular evolution of regulatory proteins and elements, and microevolution of animal development. This is an accessible text, focusing on the most well-known genes, developmental processes and taxa. It builds logically from developmental genetics and regulatory mechanisms to evolution at different genetic morphological levels. It adds major insights from recent genome studies, new evo-devo biology research findings, and a new chapter on models of variation and divergence among closely related species. It provides in-depth focus on key concepts through well-developed case studies. It features clear, 4-color illustrations and photographs, chapter summaries, references and a glossary. It presents the research of Dr. Carroll, a pioneer in the field and the past president of the Society for Developmental Biology.