Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
You can't tickle yourself.
29
After age 30, the brain shrinks a quarter of a percent (0.25%) in mass each year.
139
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14
Human hair and fingernails continue to grow after death.
7
Gorillas can catch human colds and other illnesses.
205