Do animals sleep and, if so, how much? Read here about the fascinating sleeping patterns of animals - including humans.

A study on birds finds that when jackdaws are sleep-deprived, they stop sleeping with one eye open and enter deeper sleep, risking safety.

And for people living on their own, it could be nice to have something to cuddle with at night ... animals can help with better sleep by providing a signal to the brain that it is time to wind ...

ruby-colored at night when the fire-red pupils expand. It spends the hours from dusk to midnight dancing, sleeps till dawn. The impulse to dance may seize it any time during the day. Rest periods ...