Some animals do it for survival, while others have evolved this ability for different reasons. It might seem strange, but these animals have developed abilities to rest while staying alert to their ...

If you’ve ever shared a bed with someone with nocturnal lagophthalmos, especially if they didn’t warn you in advance, it’s ...

The animal kingdom is full of fascinating adaptations, and one of the most intriguing is the ability to sleep with one eye open. While humans drift into deep slumber with both eyes closed, several ...

Have you heard the saying about “sleeping with one eye open”? It’s a bit of metaphoric advice about staying vigilant—and a way to describe very light restless sleep. But sleeping with eyes open is ...