No one, except delusional sexist men, will be surprised to learn that men who harass women online are "low-status, non-dominant men" according to a study published in the journal PLOS One, titled "Insights into Sexism: Male Status and Performance Moderates Female-Directed Hostile and Amicable Behaviour." The Washington Post reports:

Michael Kasumovic and Jeffrey Kuznekoff, researchers at the University of New South Wales and Miami University, respectively … watched how men treated women during 163 plays of the video game Halo 3. As they watched the games play out and tracked the comments that players made to each other, the researchers observed that — no matter their skill level, or how the game went — men tended to be pretty cordial to each other. Male players who were good at the game also tended to pay compliments to other male and female players.

Some male players, however — the ones who were less-skilled at the game, and performing worse relative their peers — made frequent, nasty comments to the female gamers. In other words, sexist dudes are literally losers.

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In each of these environments, Kasumovic suggests, a recent influx of female participants has disrupted a pre-existing social hierarchy. That's okay for the guys at the top — but for the guys at the bottom, who stand to lose more status, that's very threatening. (It's also in keeping with the evolutionary framework on anti-lady hostility, which suggests sexism is a kind of Neanderthal defense mechanism for low-status, non-dominant men trying to maintain a shaky grip on their particular cave's supply of women.)