Sleeping underwater presents a serious challenge for animals that still need oxygen to survive. Different species have ...

Sleep is one of life’s most universal behaviors. Despite its ubiquity, it’s also one of the most mysterious. Humans spend about a third of their lives with their eyes closed and their brains in states ...

Sleep is important for everyone, but some animals take it to a whole new level. While humans usually need around seven to ...

This is read by an automated voice. Please report any issues or inconsistencies here. Animals such as penguins and frigatebirds have evolved extreme sleep strategies — naps that last a few seconds, ...

Some animals appear lazy at first glance, spending large portions of the day asleep or resting. In reality, frequent naps ...

Sleep looks peaceful on the outside, but inside the brain, it is anything but ...

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 ...

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 ...