Meet Nat Geo Explorer in Residence and award-winning paleoanthropologist Prof. Lee R. Berger. His explorations into human origins on the African continent, Asia, and Micronesia for the past three decades have resulted in groundbreaking discoveries, including the discovery of two new species of early human relative–Australopithecus sediba and Homo naledi. Berger's latest discovery—announced yesterday: http://on.natgeo.org/6184OxKgE | National Geographic Society

National Geographic Explorer Martin Edström spent more than a week exploring and documenting Vietnam’s Son Doong Cave, one of the world’s largest, to create a one-of-a-kind immersive experience he calls “interactive journalism.” Experience the full interactive here—and chat with Martin live via Twitter on Thursday, May 28th at 11am EST by using #SonDoong360: http://bit.ly/1AaTxYp | National Geographic