Yawning is a complex reflex that may be triggered by changes in state of being, but its purpose is still unknown.

Is it true that we yawn when our brains are deprived of oxygen? Most of us can feel a yawn coming on. The muscles in our jaw begin to tighten, our nostrils might flare, and our eyes might tear up ...

Researchers at Mie University said the finding indicates yawning is possible underwater without taking air in, despite the conventional definition that the behavior entails breathing. The ...

Morisaka said the definition of yawning should be modified and called for future studies focusing on open-mouth movements. He said he plans to do comparative studies on whales and other species.