Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
Hot water can freeze faster than cold water.
181
One 75-watt bulb gives more light than three 25-watt bulbs.
57
The only letter not appearing on the Periodic Table is the letter "J".
180
Kissing actually has the biological purpose of passing on biological information and chemical signals to assess mating possibilities and status.
9
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Sound travels about 4 times faster in water than in air.
408