Mystery #1Tier 1body / sleep
Why must you spend a third of your whole life fast asleep?
You will spend around a third of your entire life asleep. That is roughly 25 years of a long life spent doing, on the face of it, absolutely nothing: lying still with your eyes shut. Evolution is ruthless about wasting time, yet it kept sleep for almost every animal on Earth. So what is really going on while you snooze?
Your guess
What do you reckon your brain and body are up to while you sleep?
There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.
Make a guess to unlock the hints and the answer.