In this episode, Xavier Bonilla has a dialogue with Jeremy DeSilva about the importance of bipedalism. They discuss the evolutionary history of hominoids, hominins, and hominids. They talk about the earliest evolution of bipedalism in other species. They also discuss the importance of Lucy and Ardi and the differences and similarities between these two early Australopithecus. They talk about where Homo Erectus fits into the timeline and whether bipedalism was essential for human evolution. They engage about the elements of gait for different human species and the relevance for modern humans. They also talk about bipedalism and the aspects of birth, socialization, and many other topics. 
Jeremy DeSilva is a paleoanthropologist and Associate Professor of anthropology at Dartmouth College. He specializes in the locomotion of the first apes and early human ancestors. Specifically, he studies fossils of human ankles and feet to understand the evolution of bipedalism. His book, First Steps: How Upright Walking Made Us Human is available here. You find him at his website and also on Twitter: @desilva_jerry