Why did cave men paint in walls?

Aboriginals had wall paintings the walls of caves to tell traditional stories and mark that they were there. ==new answer== The picture language is universal. Even foreigners visiting the states recognize the symbology represented in pictures, such as when it is safe to cross at an intersection. The best way to begin to understand this language is to work with your dreams. Use the universal language of mind which is the picture language. Then look at those wall paintings and see what is there.