Guys, she may be hopping mad. And you, being guys, just haven’t got a clue.

Psychology grad student Lisa Goos of Toronto showed college students photos of male and female faces displaying four emotions: anger, fear, disgust, or sadness. While the men correctly identified anger in other men about 40 percent of the time, they had a harder time identifying anger in women.

Goos believes this is a natural result of evolution, which dictates that what’s important for survival will be perpetuated. Men learn to recognize anger in other men because an angry man could pose a physical threat. But an angry woman is not something to worry about.

Oh yeah?