Climate Instability and the Evolution of Human Adaptability

How environmental dynamics may have shaped the adaptations of early human ancestors is one of the profound questions in the study of human evolution. A synthesis of African paleoclimate data suggests that significant events in human origins tended to occur during lengthy eras of strong climate fluctuation. For example, the origin of several hominin genera, major stone technologies, and key dispersal events all corresponded with prolonged intervals of increased climate variability. Between 350,000 and 200,000 years ago, complex climate dynamics and resource uncertainty coincided with early expressions of adaptive versatility and innovation prior to the origin of Homo sapiens, evident in the expansion of mobile technologies, symbolic behavior, and social networks. An increasing ability to alter the surroundings, associated with the evolution of adaptability during eras of climate uncertainty, has become an important new theme in the environmental story of human origins.