Cows can sleep standing up, but they can only dream lying down.
745
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Some monks can increase their body temperature so much they can dry soaking sheets in a freezing room!
31
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81