Guest host Meagan Cantwell talks to Staff Writer Erik Stokstad about a new weapon against crop-destroying beetles. By making pesticides using RNA, farmers can target pests and their close relatives, leaving other creatures unharmed.  Next, freelance producer Katherine Irving talks to hydrologist Craig Brinkerhoff about a recent analysis of ephemeral streams—which are only around temporarily—throughout the United States. Despite their fleeting presence, Brinkerhoff and his colleagues found these streams play a major role in keeping rivers flowing and clean. Brinkerhoff is currently a postdoctoral fellow at Yale University, and completed this work as a Ph.D. student at the University of Massachusetts Amherst.   Finally, the next segment in our books series on a future to look forward to. Books host Angela Saini talks with author Rachel O’Dwyer about her recent book Tokens: The Future of Money in the Age of the Platform. They’ll discuss new and old ideas of currency, and what it means to have our identities tied to our money as we move toward a more cashless society. This week’s episode was produced with help from Podigy. About the Science Podcast Learn more about your ad choices. Visit megaphone.fm/adchoices