You Wouldn't Want to Live Without Sleep!

Most people spend a third of their life sleeping - around 25 years or more! Like it or not, we all have to sleep. Yet sleep is also very mysterious. No one really knows why we do it. And how do we explain all those strange dreams? What scientists do understand, however, is that sleeping is essential for health and happiness. Learn about the strange sleep cycles throughout the animal kingdom, and the theories behind why people get tired or have terrifying nightmares.