French and Spanish Upper Paleolithic cave art was drawn forty thousand to eleven thousand years ago, and it was motivated by climate change. Kieran D. O'Hara, a geologist and professor emeritus at the University of Kentucky, explains why we know that to be true in this groundbreaking book. His goal isn't to explore the meaning of cave art but to show why it was done. While many scholars argue that the art depicted in these caves don't...