Enamel is hardest substance in the human body.
61
Our Right Lungs takes more air than our left lung.
194
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
A man's beard grows fastest when he anticipates sex.
239
The human sigh acts as a physiological reset button.
23
The average sperm cell swims at 8 inches per hour.
4
Modern humans first appeared about 200,000 years ago, but record keeping didn't begin until about 6,000 years ago. That means about 97% of human history is lost.
21