The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
A third of the human population sneezes when they look at the Sun. Light can signal the ocular nerve near the sinuses and triggers a sneeze.
18
Fingers prune underwater not because of them absorbing the water or washing away the oil, but because of an evolutionary trait caused by the brain to enhance the grip of your fingers underwater.
24
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Your heart will pump about 212 million liters in its lifetime.
26
It takes approximately 12 hours for food to entirely digest.
93