In 30 minutes, the average body gives off enough heat (combined) to bring a half gallon of water to boil.
198
A human brain produces as many as 12,000 to 50,000 thoughts per day, depending on how deep a thinker a person is.
23
It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
Only humans shed emotional tears.
331
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Mushrooms are more closely related to humans than they are to plants.
47
Early American humans hunted car-size armadillos and used their shells for houses.
12