Dolphins Smile to Signal Playmates: Research Uncovers Why

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Dolphin Grin

Dolphin smiles are contagious, literally. The slippery mammal’s “open mouth” gesture is used intentionally to signal play.

• Occurs almost exclusively in dolphin-dolphin play

• 89% of “smiles” happen within playmate’s field of view

• 33% of “smiles” are returned, suggesting intent (instead of at random)

Potentially evolved from playful biting, the dolphin grin is not technically the human definition of smiling. Future studies will look for other non-verbal communications during dolphin playtime. “Wink once if you’re the best dolphin ever!”

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