Leif Ristroph is an experimental physicist and applied mathematician who specializes in fluid dynamics at NYU. His team has been experimenting with the creation of yardangs, organic formations through natural erosion. Their work has led to the theory that the Sphinx may have been shaped by natural forces before humans finished the job and created one of the most famous landmarks of the ancient world.

This episode of Unlocking the Past with Eric Erickson is brought to you by History's Trainwrecks and the bestselling book, How To Start A Podcast in Less Than A Day. Also look for Virginia Dare and Ascension, available now.