Apply molecular genetics to ecology, conservation, and evolutionary questions Advances in genetic technology continue to reshape how ecologists study local adaptation, dispersal, phylogeography, behavioural ecology, and conservation biology. Now in its Fourth Edition, Molecular Ecology by Joanna R. Freeland provides an updated account of how molecular biology and population genetics illuminate ecological and evolutionary processes across virtually all taxonomic groups. This edition incorporates recent references and research developments to reflect the current state of the discipline. Coverage spans environmental change and genetic diversity, landscape genetics, taxonomic classification of communities and prey items, the evolutionary processes associated with invasive species and hybrids, and the evolution of mating systems. Examples and case studies have been selected specifically to engage upper-level undergraduate students with relevant, accessible applications of molecular data. Readers will also find: Updated coverage reflecting the latest breakthroughs in molecular ecology research methods and analytical approaches across diverse taxonomic groupsTargeted case studies and examples selected to connect molecular genetic concepts with real-world ecological and conservation questionsApplications of population genetics principles for understanding dispersal, gene flow, and connectivity among natural populations Discussions of how environmental change influences genetic diversity within and among populations of plants and animalsAccessible presentations of phylogeography, behavioural ecology, and the genetic underpinnings of biological invasions and adaptation Molecular Ecology serves advanced undergraduate students in molecular ecology and ecological genetics courses, as well as postgraduate students seeking foundational background reading. By connecting molecular genetic data directly to ecological and evolutionary questions, this text prepares readers to interpret and apply genetic approaches in research and conservation practice.