The bark of an older redwood tree is fireproof.
65
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Scientists aren't sure what color dinosaurs were.
312
A cubic yard of air weighs about 2 pounds at sea level.
31
Out of all the senses, smell is most closely linked to memory.
146