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
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
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 oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Every human spent about half an hour as a single cell.
144
The world's shortest man measures only 21.5 inches.
73
The human sigh acts as a physiological reset button.
23
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118