At a moment when society feels dangerously polarized, fragmented and unstable, the symposium “Our Tribal Nature: Tribalism, Politics, and Evolution” offers a forum for understanding our human urge to form alliances. On September 19, leading anthropologists, authors, psychologists, and political scientists including Sebastian Junger, Richard Wrangham, and Francis Fukuyama will gather at the Morgan Library in New York to examine the evolutionary origins and function of tribalism, our social transition from tribes to states, and the role tribal identity plays in our increasingly divided world.