Yawns are more contagious among people with closer relationships.
163
Yu Youzhen, a Chinese millionaire, works as a street sweeper for the sanitation department to set an example for her children.
11
Roughly a quarter of the world's people live in China.
50
Someone on Earth reports seeing a UFO every three minutes.
180
Americans throw out 4.5 pounds of trash a day - twice that of 40 years ago.
76
One in 500 humans has one blue eye and one brown eye.
145