The human sigh acts as a physiological reset button.
23
You forget 90% of your dreams.
256
Enamel is hardest substance in the human body.
61
Early American humans hunted car-size armadillos and used their shells for houses.
12
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
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Humans are capable of running 40 mph according to a study by bio-mechanical expert Dr. Matthew Bundle. Today's fastest man, Usain Bolt, has a top speed of 28 mph.
34