This book adopts a human ecology approach to present an overview of the biological responses to social, political, economic, cultural and environmental changes that affected human populations in the Yucatan Peninsula, Mexico, since the Classic Maya Period. Human bodies express social relations, and we can read these relations by analyzing biological tissues or systems, and by measuring certain phenotypical traits at the population level. Departing from this theoretical premise, the contributors to this volume analyze the interactions between ecosystems, sociocultural systems and human biology in a specific geographic region to show how changes in sociocultural and natural environment affect the health of a population over time.