One in 500 humans has one blue eye and one brown eye.
145
People with blue eyes are better able to see in the dark.
153
Studies show that the risk of a “secret love” being revealed heightens romantic feelings for the partners, thanks to increased levels of phenylethylamine (PEA).
99
Roughly a quarter of the world's people live in China.
50
It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
People who have a strong friendship possess the ability to communicate with one another through facial expressions.
46
The average person falls asleep in seven minutes.
115