C reatures that sleep during the day and are active at night are known as nocturnal, and they take the form of both predators ...

January often feels like a month when we should be hibernating, emulating a dormouse or a hedgehog and tucking ourselves up ...

other species have different ideas about what constitutes a good night’s (or day’s!) sleep. BBC Bitesize takes a look at the surprising ways four different animals get their shut-eye.

Cats have different sleep-wake cycles than other animals and are often busy at night. This is because cats are crepuscular, which means they hunt and are active in the evening or early morning.

What has puzzled researchers and philosophers for many centuries is the ‘why’ of sleep, along with the ‘how’. We human ...

Artificial lights at night are causing serious disruption to these insect night shift workers. That’s a problem for everyone.

All animals need sleep. Explore why and how it evolved ... jellyfish also sleep I was so engrossed in writing the paper last night that I didn't notice how late it was getting.

The researchers argued that the findings show sleep doesn’t have to be in one long block to be helpful. For some animals, even small bits of sleep can add up and be useful (see graphic).