The world's youngest parents were 8 and 9 and lived in China in 1910.

You can tell the age of a whale by looking at the wax plug in its ear. This plug in the ear has a pattern of layers when cut lengthwise that scientists can count to estimate the age of the whale.

Braces were first invented by Pierre Fauchard in 1728. The braces were made by a flat strip of metal, which was connected to the teeth by thread.

AMAZING FACTS