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 body contains over a billion miles of DNA.
147
It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
By weight, Bone is five times stronger than steel.
417
You forget 90% of your dreams.
256
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Your heart will pump about 212 million liters in its lifetime.
26