On this very special episode, Razib talks to paleoanthroplogists John Hawks and Chris Stringer. Hawks is a paleoanthropologist who has been a researcher and commentator in human evolutionary biology and paleoanthropology for over two decades. With a widely read weblog (now on Substack), a book on Homo naledi, and highly cited scientific papers, Hawks is an essential voice in understanding the origins of our species. He graduated from Kansas State University in 1994 with degrees in French, English, and Anthropology, and received both his M.A. and Ph.D. in Anthropology from the University of Michigan, where he studied under Milford Wolpoff. He is currently working on a textbook on the origins of modern humans in their evolutionary context. Hawks has already been a guest on Unsupervised Learning three times.

Chris Stringer is affiliated with the Natural History Museum in London. Stringer is the author of African Exodus. The Origins of Modern Humanity, Lone Survivors: How We Came to Be the Only Humans on Earth and Homo Britannicus - The Incredible Story of Human Life in Britain. A proponent since the 1970's of the recent African origin of modern humans, he has also for decades been at the center of debates around our species' relationship to Neanderthals. In the 1980's, with the rise to prominence of the molecular model of "mtDNA Eve," Stringer came to the fore as a paleoanthropological voice lending support to the genetic insights that pointed to our African origins. Trained as an anatomist, Stringer asserted that the fossil evidence was in alignment with the mtDNA phylogenies, a contention that has been broadly confirmed over the last five decades.

Razib, Hawks and Stringer discuss the latest work that has come out of Yuxian, China, and how it updates our understanding of human morphological diversity, and integrate it with the newest findings about Denisovans from whole genome sequencing. They talk about how we exist at a junction, with more and more data, but theories that are becoming more and more rickety in terms of explaining the patterns we see. Hawks talks about the skewing effect of selection on phylogenetic trees, while Stringer addresses the complexity of the fossil record in East Asia.