It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
Enamel is hardest substance in the human body.
61
It has been scientifically proven that stroking a cat can lower one's blood pressure!
456
A human being loses an average of 40 to 100 strands of hair a day.
133
You can't tickle yourself.
29
In ancient Egypt, priests plucked EVERY hair from their bodies, including their eyebrows and eyelashes.
130
Your heart will pump about 212 million liters in its lifetime.
26
A person can live without food for about a month, but only about a week without water.
156