Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
A man's beard grows fastest when he anticipates sex.
239
Due to the angle at which the optic nerve enters the brain, staring at a blue surface during sex greatly increases the intensity of orgasms.
252
You can't tickle yourself.
29
Your thumb is about the same size as your nose.
124
A person can live without food for about a month, but only about a week without water.
156
On average, there's 100 billion neurons in the human brain.
83
Enamel is hardest substance in the human body.
61