Study Reveals Dolphins 'Smile' During Playful Interactions

Researchers find that bottlenose dolphins use an open-mouth gesture similar to a human smile to communicate playfulness with their peers.

Dolphins exhibit a distinct open-mouth facial expression, akin to a human smile, primarily during social play.
The gesture, observed in 92% of dolphin-dolphin play sessions, is used when dolphins are in each other's field of view.
A third of the time, dolphins quickly mimic the open-mouth expression when they see it on a playmate.
Researchers believe this expression evolved from a biting action, signaling playful intent without aggression.
Future studies aim to explore the role of vocalizations and tactile signals in dolphin play communication.