One of the mysteries of bees is how they create their combs with perfect six-sided cells. It's pretty amazing, but it's not as mystical as it seems. The method is actually practical and commonsensical. The key is that the cells are not really hexagons. They're round. They are the size that a bee can fit comfortably into, because the bees working from inside the cells use themselves as a measuring device. Why do they seem to be six-sided? Easy. Try this. Raid your penny jar and put a penny on the table. Now arrange coins in a circle around the outside of the first coin. How many will fit? Six. So, simply building round combs as tightly as possible gives the bees something very closely resembling a hexagon.