Men have been the dominant sex since the dawn of mankind. But Hanna Rosin has noticed that this long-held truth is, astonishingly, no longer true. At this unprecedented moment, by almost every measure, women are no longer gaining on men: they have pulled decisively ahead.. In this landmark book, Rosin reveals how this new state of affairs is radically shifting the power dynamics between men and women at every level of society, with profound implications for marriage, sex, children, work, and more. With wide-ranging curiosity and insight unhampered by assumptions or ideology, Rosin shows how the radically different ways men and women today earn, learn, spend, couple up--even kill--has turned the big picture upside down.