An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
A person will create enough saliva to fill two average size swimming pools during his lifetime.
191
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Yawns are more contagious among people with closer relationships.
163
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
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
In one day, adult lungs move about 10,000 litres of air.
11