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
The human brain uses approximately as much energy as a 10 watt light bulb.
120
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Only humans shed emotional tears.
331