Mark Oppenheimer, a part-time stay-at-home father of two young girls, is used to stares. “When I'm walking down the street with one baby strapped to my chest and the other in a stroller—and the kids all look happy—and I walk by a group of mothers, they're just blown away,” he says. “The easiest way in the world to get a smile is to be a man with a baby.”
Fatherhood has undergone a profound change in the past half a century. In 1965 fathers were spending 2.6 hours a week on child care; by 2000 that figure had reached 6.5 hours. There are three times as many stay-at-home fathers as there were a decade ago, and families headed by single fathers are the fastest-growing household type in the U.S. “When I started studying American mothers and fathers, the majority of the fathers I studied had never bathed their children. Many of them had never changed a diaper,” says developmental psychologist Michael Lamb of the University of Cambridge. That was in the 1970s. “Now,” he says, “men would feel embarrassed to say they hadn't changed their children.”
For years social scientists considered fathers to be second-string parents, bench players whose main role was to jump in when Mom was otherwise engaged. That view has changed, partly thanks to research revealing that dads are anything but backup mothers. Scientists are now turning to the nuances of how and why they matter. The work shows that fathers are biologically as responsive to their children as mothers are. And yet fathers seem to influence children in unique ways. In particular, they play an outsized role in challenging their kids and stretching their emotional and cognitive capabilities, preparing them for the big wide world.