Cows can sleep standing up, but they can only dream lying down.
745
You forget 90% of your dreams.
256
In Georgia, there is an airtight room called the Crypt of Civilization that was sealed in 1940. It contains numerous artefacts documenting what life was like at the time of sealing, and is scheduled to be opened in the year 8113 to show people of the future exactly what life was like.
13
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
In the last 7 years, humanity has discovered 43 potentially habitable planets.
14
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81
Only about 2% of the world population has green eyes.
36