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Real men are made, not born — so goes the conventional wisdom. In other words, 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.

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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?

In one study, the researchers had asked participants to fill in 25 sentence stems that began either “A real man…” or “A real woman…” The results, as described in a subsequent paper published recently in Current Directions in Psychological Science:

[J]udges coded the sentence completions according to whether they contained actions (e.g., momentary behaviors that people do, such as “drives a flashy car”) or adjectives (e.g., enduring qualities that cannot be lost, such as “is honest”). Findings revealed that men, but not women, described “a real man” with more fleeting actions than enduring adjectives, and they described “a real woman” with more enduring adjectives than fleeting actions. Notably, this pattern emerged when we controlled for the gender-stereotypical content of the sentence completions. When men completed “real man” sentences with gender atypical content (e.g., “A real man cooks dinner”), they still used action language to do so. Thus, men define their own gender status in terms of the active things that men do rather than the ways that men are.

This may help explain why men take more physical risks than women do — risks and physical aggression are convincing ways to prove manhood, especially when it’s been threatened, the authors said.

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Case in point: in another study, the researchers presented college students with a mock police report in which either a man or woman punched a same-sex stranger who taunted him (or her) publicly and questioned his manhood (or her womanhood) in front of a potential romantic partner. The students were asked to judge the motivations of the hitter. When women read about the male aggressor, and when both men and women read about the female aggressor, they attributed the punching to internal reasons like “his/her own immaturity” or “the kind of person he/she is typically.”

But when men read about the male aggressor, they said they believed his actions to have been caused by external factors like “being provoked by the stranger” or “being publicly humiliated.” “Men displayed a unique sensitivity to the situational factors that compel men to defend their gender status with aggression,” the authors wrote.

To test whether this cognitive bias would translate into real-life aggression, the researchers set up an experiment to threaten men’s masculinity — by asking them to braid hair. (A control group braided a rope.) After they had completed the braiding, the men were offered a choice of punching a bag or solving a puzzle. Those who braided hair were more likely than men who got the rope to punch the bag; in a follow-up experiment in which both groups were allowed to punch a pad, the hair-braiders punched harder.

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In a third take on the experiment, male participants braided hair and then either punched or didn’t punch a bag. Afterward, the researchers found, men who got to punch something displayed less anxiety than the guys who did nothing. “Thus, these findings provide converging evidence that men use displays of physical aggression to restore threatened manhood,” the authors wrote.

Why does any of this matter? Because the fact that men perceive their manhood to be so precarious has repercussions for behavior in all aspects of life — at work, in relationships, in their health. Indeed, an unrelated study recently found that the more “macho” guys were, the less likely they were to seek preventive health care, despite being highly educated or wealthy. Masculinity could help explain why men have lower life expectancy than women.

The authors said this research also begins to illuminate the negative effects of gender on men — depression, anxiety, low self-esteem and violence. And, at the very least, it may persuade ladies to cut their guys a little slack. “When I was younger I felt annoyed by my male friends who would refuse to hold a pocketbook or say whether they thought another man was attractive. I thought it was a personal shortcoming that they were so anxious about their manhood. Now I feel much more sympathy for men,” Bosson said in a statement.