Human laugh lines traced back to ape ancestors
Playing chimps’ facial expressions signal that mirthful communication evolved early on
![chimps laughing](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2015/06/bb_laughing-chimps_feat_free.jpg?fit=860%2C460&ssl=1)
LAUGH IT UP Chimps at play make laughlike, open-mouth faces, whether or not they’re laughing out loud, a new study finds. That means that humans’ versatile communication with open-mouth expressions may have its origins in an ancient ape ancestor, researchers say.
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