Manhood is a social status, something a guy earned historically, through brutal tests of physical endurance or other risky demonstrations of toughness that mark the transition from boyhood to manhood. But while that masculinity is hard-won, it can be easily lost.
Once earned, men have to continue proving their worth through manly action. In modern society, that may no longer mean, say, killing the meatiest wooly mammoth, but there are equivalent displays of masculinity: earning a decent living or protecting one’s family. One misstep — losing a job, for instance, or letting someone down — and that gender identity slips away.
The phenomenon helps explain why men are so touchy about their masculinity. Women don’t have the same problem, of course. Womanhood is largely seen as something innate, immutable: girls become women through puberty; once achieved, womanhood sticks.
In a series of studies, psychologists Jennifer K. Bosson and Joseph A. Vandello at the University of South Florida decided to probe this idea further. Specifically, they wanted to know, do modern men still use physical action and aggression to prove their manhood?
The Bosson & Vandello article cited by TIME is available here (PDF-subscription required).