20 inches high x 13.50 inches high 24 inches wide Image: 16.50 inches wide 25 inches ...

Sometime in the Stone Age, human artists began experimenting with a new form of visual art: drawing. Now, from the ancient rubble that accumulated on the floor of a South African cave comes the ...

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American Hashtags have become a standard in ...