Test: Can You Tell a Dominant Chimp Just by Looking at Its Picture?

You probably shouldn't judge a book by it's cover, but if you do, you probably do it accurately.

That's the takeaway from a new study at Bangor University in Wales. Using several groups of test subjects, researchers discovered that, when shown images of chimp faces bearing neutral expressions—i.e. not grinning or howling—people were usually able to ascertain which chimps were most dominant, most active, and most sympathetic.

In one experiment, subjects were shown a juxtaposition of different chimps of the same sex (like in the image above), then asked to guess which chimp was more dominant. Fascinatingly, 70 percent of the subjects guessed correctly.

Scientists don't know exactly what about the chimps faces make them so telling, and they don't yet know if human faces are as expressive. They hypothesize, however, that the ability to both exude personality via features and pick up on others' personalities from a look alone was helpful to our ancestors: "Our faces could be windows into our souls because our ancestors developed them as ways to honestly tell others about ourselves—knowledge that could help social interactions proceed more smoothly."

It's also worth considering the problems with making these snap judgments, though. Just because someone has a "dominant" face doesn't make them dangerous, of course, but it's very possible employers might subconsciously be wary of apparently dominant candidates. And what of law enforcement officers, who may be rougher with dominant faces than they are with sympathetic faces?

To test yourself, try and guess which chimp is more dominant in the image above. No peeking at the answer below.

(The more dominant chimp is on the right.)