Kissing actually has the biological purpose of passing on biological information and chemical signals to assess mating possibilities and status.
9
In zero gravity, a candle's flame is round and blue.
16
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
In the 60s, a scientist gave LSD to dolphins in an attempt to teach them English.
17