Nicholas A. Christakis, M.D., Ph.D., M.P.H., is a social scientist and physician who conducts research on social and biological factors that affect human health and behavior. He directs the Human Nature Lab at Yale University and is the Co-Director of the Yale Institute for Network Science. He is the Sol Goldman Family Professor of Social and Natural Science at Yale University. Dr. Christakis also serves as a Gallup Senior Scientist.

Dr. Christakis' current work focuses primarily on the origins and functions of human social networks. This research explores two types of phenomena: connection, the social, mathematical and biological rules governing how social networks form; and contagion, the biological and social implications of how social networks operate and how they dictate the spread of thoughts, feelings and behaviors. Understanding these processes allows us to understand how networks affect our health, creativity, security and wealth.

Using both observational and experimental methods, Dr. Christakis explores how phenomena as diverse as obesity, smoking, happiness, infection, vaccination, altruism, innovation, civic engagement and purchasing behavior can spread through social networks. His lab invents and evaluates methods for facilitating large-scale population-level behavior change to affect health and diverse other outcomes, such as cooperation, purchasing and voting behaviors. He conducts large-scale online and offline experiments to evaluate how network-based interventions might improve health, cooperation, innovation and productivity in places as diverse as villages in the developing world, websites, hospitals and businesses. Recently, Dr. Christakis has also become interested in the genetics and evolutionary biology of social network structure. His book with James Fowler, Connected: The Surprising Power of Our Social Networks and How They Shape Our Lives, has been translated into nearly 20 languages and has been widely reviewed.

Dr. Christakis received his bachelor's degree from Yale University, his medical degree from Harvard Medical School, his master's of public health degree from the Harvard School of Public Health and his doctorate from the University of Pennsylvania. Dr. Christakis has served on many editorial boards and review committees in the United States and abroad. Over the past several years, he has given invited talks in over 20 countries around the world. He has taught quantitative research design, social epidemiology, medical sociology and palliative medicine.

Dr. Christakis was elected to the Institute of Medicine of the National Academy of Sciences in 2006 and was made a Fellow of the American Association for the Advancement of Science in 2010. He was named by TIME magazine to its annual list of the 100 most influential people in the world in 2009. He was listed by Foreign Policy magazine in its annual list of Top 100 Global Thinkers in 2009 and in 2010.