The Nose Knows

When we started out ll in our mother's womb, how did all those our new cells know to hook up to each other to knit together our nerve connections? How did other cells know to hook up with each other to make our circulatory system, or form the heart?

A fascinating new theory has now been proposed, based on the fact that every cell in your body has the same active genes that your nose uses to enable you to smell.