Pain occurs when sounds are above 130 db.
124
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
132
The human body contains over a billion miles of DNA.
147
Enamel is hardest substance in the human body.
61
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
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Every human spent about half an hour as a single cell.
144