Animals have evolved to sleep in extreme ways — for example, taking micro naps during parenting, sleeping on the wing during migrations and dozing while diving.

Every animal with a brain needs sleep — and even a few without a brain do, too. Humans sleep, birds sleep, whales sleep and even jellyfish sleep. Sleep is universal “even though it’s actually very ...

Turns out jellyfish and sea anemones – among the ancient creatures with a nervous system instead of a brain – have a very similar sleeping routine to our own. A new study published in Nature ...

Every animal with a brain needs sleep — and even a few without a brain do, too. Humans sleep, birds sleep, whales sleep and even jellyfish sleep. Sleep is universal “even though it’s actually very ...

What has puzzled researchers and philosophers for many centuries is the ‘why’ of sleep, along with the ‘how’. We human animals know from experience that we need to sleep, and that the longer we go ...

As every seasoned cat parent knows, cats sleep a lot. Chances are your furry feline is presently snoozing. Cats sleep so much that many new parents become concerned! However, in most cases, it is ...

A protective mucous cocoon surrounds this parrotfish as it sleeps in Australia's Great Barrier Reef. This layer of protection helps fend off predators so parrotfish can get a good night's rest.

A new study analyzed the sleep patterns of jellyfish and sea anemones and found they share some sleep traits with humans. The ...