Throughout the history of Homo sapiens, skin pigmentation has been a highly labile trait, and similar skin tones have evolved independently numerous times. Skin pigmentation results from an evolutionary compromise between the conflicting demands of protection against ultraviolet radiation and production of vitamin D, and represents one of the best examples of evolution by natural selection acting on the human body. Because skin color is one of the most visible of human traits, it has been used as the primary characteristic for classifying people into races. Dr. Jablonski will discuss the history of skin-based race concepts and the meaning of skin color in the modern world, including its implications for health.
Nina G. Jablonski is Distinguished Professor of Anthropology at The Pennsylvania State University. A biological anthropologist and paleobiologist, she studies the evolution of adaptations to the environment in Old World primates including humans. Her research program is focused in two major areas. Her paleoanthropological research concerns the evolutionary history of Old World monkeys, and currently includes an active field project in China. Her research on the evolution of human adaptations to the environment centers on the evolution of human skin and skin pigmentation, and includes an active field project examining the relationship between skin pigmentation and vitamin D production. Jablonski is currently involved in the development of new approaches to evolution education in the United States, including the development of a new "genetics and genealogy" curriculum for middle school students. At Penn State, she directs the newly formed cross-college Center for the Study of Human Diversity, Evolution, and Behavior.
Dr. Nina Jablonski, Professor of Anthropology at the Pennsylvania State University, discusses the biology of red-haired, freckled complexions. Jablonski explains how the unique form of melanin in freckles may have an advantage among areas of low average ultraviolet radiation like Ireland or Scotland, but can cause problems at lower latitudes.