By weight, Bone is five times stronger than steel.
417
The human sigh acts as a physiological reset button.
23
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
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
If your DNA was stretched out it would reach to the moon 6,000 times.
256
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
You can't tickle yourself.
29