While researching a story about the endangered status of native trillium in North America recently, I was happy to meet today’s guest, botanist Wesley Knapp. 



Our trillium conversations got me thinking about how headlines like the trillium one, highlighting reports of the accelerating threats of extinctions of plant or animal species, are so common in the news these days. 





But how are those predictions calculated, I wondered, and also: do we know what species are already gone? Wesley Knapp, a Ph.D. student at University of North Carolina at Chapel Hill, is Chief Botanist at NatureServe, the authoritative source for biodiversity data in North America. He previously worked as a Botanist and Ecologist for the Maryland and North Carolina Natural Heritage Programs.