It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
Cats have a weak sense of taste. They have only 473 tastebuds, humans have 9,000.
307
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
In ancient Egypt, priests plucked EVERY hair from their bodies, including their eyebrows and eyelashes.
130
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
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
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82