By weight, Bone is five times stronger than steel.
417
Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
A person will create enough saliva to fill two average size swimming pools during his lifetime.
191
On average, there's 100 billion neurons in the human brain.
83
Crying literally alleviates stress and uniquely allows humans to decrease feelings of anger and sadness.
24
A person can live without food for about a month, but only about a week without water.
156
Tigers can see 6 times better at night than humans.
305