Early American humans hunted car-size armadillos and used their shells for houses.
12
By weight, Bone is five times stronger than steel.
417
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.
35
Enamel is hardest substance in the human body.
61
The world's shortest man measures only 21.5 inches.
73
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
132