There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
The human brain is more active during sleep than during the day.
28
Human hair and fingernails continue to grow after death.
7
Enamel is hardest substance in the human body.
61
A human brain produces as many as 12,000 to 50,000 thoughts per day, depending on how deep a thinker a person is.
23
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
A man's beard grows fastest when he anticipates sex.
239