The human brain doesn't stop developing until about 25 years old.
102
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The average sperm cell swims at 8 inches per hour.
76
Your thumb is about the same size as your nose.
124
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Yawns are more contagious among people with closer relationships.
163