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
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
132
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Your fingernails grow faster in summer.
744
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
When you kiss someone for the first time, you get a spike in the neurotransmitter dopamine, making you crave more.
23
The world's shortest man measures only 21.5 inches.
73