Cows can sleep standing up, but they can only dream lying down.
745
Your thumb is about the same size as your nose.
124
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
Scientists have revived a flowering plant from a fruit stored away in permafrost by Arctic ground squirrel 32,000 years ago.
16
Scientists at the Zhejiang University in China have developed an ultra-light material known as carbon aerogel.
3