Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The human brain doesn't stop developing until about 25 years old.
102
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
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