_This timeline was written by David Masci, Senior Researcher, Pew Research Center’s Forum on Religion & Public Life._ Photo credits: DNA: iStockPhoto; Madrassa: Corbis; Copernican solar

system, Corbis; Galileo: Getty Images; Isaac Newton: Corbis; Charles Darwin: Julia Margaret Cameron; Clarence Darrow and William Jennings Bryan: Corbis; Adam: iStockPhoto; Big Bang: Getty

Images; Richard Dawkins: Corbis.