It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
On average, a human being will have sex more than 3,000 times and spend two weeks kissing in their lifetime.
161
A person can live without food for about a month, but only about a week without water.
156
By weight, Bone is five times stronger than steel.
417
The average sperm cell swims at 8 inches per hour.
4
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22