Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
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Crying literally alleviates stress and uniquely allows humans to decrease feelings of anger and sadness.
24
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
The average sperm cell swims at 8 inches per hour.
4
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
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82