If Science Is So Advanced Why Can't It Explain These Mysteries?

Open Wide for a Yawn

Yawns, they are contagious and occur more often when we are tired. They make us look silly or uninterested in the worst of times. But scientists still can not explain their exact purpose. The leading theory involves bringing more oxygen to the brain in an attempt to create alertness, but this remains unproven, and thus the yawn remains firmly in the unsolved category.