Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
The smell of freshly cut grass is actually a plant distress call.
31
Sound travels about 4 times faster in water than in air.
408
4.5 pounds of sunlight strike the Earth each day.
27
During photosynthesis, plants emit light humans can’t see, but NASA can see that light from space - and they've even made maps of it!
21
The hair of an adult man or woman can stretch 25 percent of its length without breaking.
116
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118