Dolphins smile at each other to avoid misunderstandings, study reveals
A recent study published in the journal iScience has revealed that bottlenose dolphins use an open-mouthed expression, similar to a human "smile," while playing. This behavior is thought to be a tactic employed by dolphins to avoid misunderstandings with one another. The research sheds new light on the complex communication methods of these intelligent marine creatures.
Study observes dolphins 'smiling' during play
The research was conducted by a team of Italian and French scientists who studied 22 bottlenose dolphins at Zoomarine Rome and Planete Sauvage in western France. Most of the "smiles" were recorded when the dolphins were interacting with each other, not with their human trainers or while playing alone. This observation indicates that the "smile" is mainly a form of communication between dolphins.
'Smiling' dolphins: A form of communication or misinterpretation
While the study indicates dolphins "smile" to communicate during play, dolphin-communication expert Heather Hill, a professor of psychology at St. Mary's University in San Antonio, Texas, warns against jumping to conclusions. Hill admits dolphins do use an open-mouthed expression during play but is reluctant to call it a "smile." She points out that similar expressions are also seen in other situations like aggressive and solitary acts.
Dolphins: Playful creatures with complex communication
Dolphins are famous for their playful nature, complex social lives, and elaborate means of communication. They play in different ways including leaping, breaching or flipping above the water, hitting the water surface with their tail flukes, play-fighting or surfing through the waves. This study adds another dimension to our knowledge of these intelligent marine mammals and their unique ways of communicating with one another.
Dolphins' 'smile': A modified biting action?
Despite dolphins' playful reputation, their facial expressions during play had never been studied before. Other mammals, including humans and monkeys, are known to communicate with open-mouthed, smile-like expressions when playing. Scientists widely believe this behavior derives from a modified biting action without the actual contact. The recent study found that 92% of the times dolphins used the open-mouth expression, they were playing with each other.
Vocal communication: The next frontier in dolphin studies
The study also emphasized the role of vocal communication in dolphins' play. However, these signals were not captured in the present study. Livio Favaro, a zoologist at the University of Turin and corresponding author of the study, said dolphins have one of the most complex vocal systems in the animal kingdom. He said this could be an area of focus for future studies to better understand dolphin communication.
'Smiling' behavior in wild dolphins: The next step
All the dolphins studied for this research were living in captivity. However, Heather Hill said the "smiling" behavior likely happens in wild dolphins too, though perhaps less often since they have to concentrate on finding food and avoiding predators. She recommended that future research should use similar methodology to study wild species and learn their behavior in similar situations.
