More than a decade after discovering a new species dating back about 250,000 years, Lee Berger is still brimming with enthusiasm for the work he does. “Literally an hour ago I was in a cave,” Berger told CTV News from Johannesburg, South Africa. Berger’s paleoanthropology team uncovered Homo naledi in 2013 in South Africa’s Rising Star Cave. “It was the discovery of the largest assemblage of ancient human relative remains in all of human history, and it remains so to this day,” Berger said. Berger, a National Geographic explorer, remains at the site with his colleagues today, seeking fresh insights. “We have new evidence that this was an incredibly complex species—maybe one of the first species as complex as we humans are but existed hundreds of thousands of years before we became that complex,” Berger said. Berger will present Cave of Bones as part of the National Geographic Live series May 31 and June 1 at the Werklund Centre.