In this episode, Xavier Bonilla has a dialogue with Henry Gee about the history of the earth. They start by discussing Henry's background and reasons for writing the book. They discuss the big bang and origins of the earth along with how the sun and planets formed in our solar system. They talk about the importance of gravity and how early life started in the oceans. They explain how life went from unicellular to multicellular and the formation of sponges. They discuss how life formed the anus to forming a digestive tract to teeth to protective shells. They talk about the Cambrian explosion that was monumental for many lifeforms. They discuss how fish evolved into vertebrates and moved from water to land. They explain the importance of tetrapods and how plants began on the earth. They mention the importance of the Triassic and Jurassic periods on the anatomy of dinosaurs and the evolution of mammals. They talk about the importance of Homo Erectus, different human species on the earth, the future of the planet, and many other topics. 
Henry Gee is a Paleontologist and is the Senior Editor for the scientific journal Nature. He received his PhD from the University of Cambridge. Along with many articles, he is the author of numerous books including his most recent book, A (Very) Short History of Life on Earth: 4.6 Billion Years in 12 Pithy Chapters, which you can purchase here. You can find his blog here. Twitter: @endofthepier