Dave interviews Rob Wesson, author of Darwin's First Theory. In it, the USGS Scientist Emeritus follows in Darwin's footsteps from England and Scotland to the Voyage of the Beagle around the world. Darwin is of course famous for his theory of evolution by natural selection, but he was actually hired on to be a geologist for HMS Beagle English gentleman to keep Captain Robert Fitzroy company. Darwin's observations of the geologic landscapes of South America in particular, especially his documenting of the 1835 earthquake there, lead him to a theory of uplift and subsidence that is tantalizingly close to our modern theory of plate tectonics. Wesson traveled in Darwin's footsteps and immersed himself in the experience while simultaneously looking for evidence of past earthquakes and tsunamis. He recounts Darwin's brilliance as an observer of the natural landscape and discusses the tragedy of the Chilean earthquake and tsunami of 2010 along with some amazing observations confirming what Fitzroy and Darwin observed nearly two centuries before.