"A rollicking tour through humanity's evolutionary past, and von Hippel is the consummate tour guide. With equal parts wisdom, humor, authority, and charm, he shows how our past explains the present and why our well-being rests on an understanding of how our minds evolved."--Adam Alter, New York Times bestselling author of Drunk Tank Pink and IrresistibleHuman psychology is rife with contradictions: We work hard to achieve our goals, but happiness at our success is fleeting. We hope our friends will do well but can't help but feel jealous if they do too well. We're aghast at the thought of people we know being murdered, but are unconcerned when our armed forces kill enemies we've never met. We complain about difficult bosses but are often just as bad when we're in charge.These inconsistencies may seem irrational, but each evolved to serve a vital function in our lives. Indeed, the most fundamental aspects of our psychology were permanently shaped by the "social leap" our ancestors made from the rainforest to the savannah. In their struggle to survive on the open grasslands, our ancestors prioritized teamwork and sociality over physical prowess, creating an entirely new kind of intelligence that forever altered our place on this planet.A blend of anthropology, biology, history, and psychology with evolutionary science, The Social Leap traces our evolutionary history to show how events in our distant past continue to shape our lives today. From why we exaggerate to why we believe our own lies, the implications are far-reaching and extraordinary.