Early American humans hunted car-size armadillos and used their shells for houses.
12
The average sperm cell swims at 8 inches per hour.
4
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
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
Your heart will pump about 212 million liters in its lifetime.
26
When you kiss someone for the first time, you get a spike in the neurotransmitter dopamine, making you crave more.
23
On average, there's 100 billion neurons in the human brain.
83
If the human eye was a digital camera, it would have 576 megapixels.
25