Season 3, Episode 10 of 'A Window in Science' regards the demanding and sometimes dangerous biodiversity and ecosystem research in the underground Karst caves of Postojna, Slovenia. Karst is a special type of landscape that is formed by the dissolution of soluble rocks, including limestone and dolomite, and Karst regions contain aquifers that are capable of providing large supplies of water. More than 25 percent of the world's population either lives on or obtains its water from karst aquifer...