Yellow Fever and Ebola, Trans-boundary Aquifers, Probiotics. Aug 24, 2018, Part 2 Listen Download Embed Share Share this on Facebook (Opens in a new window) Share this on Twitter (Opens in a new window) Share this via Email The Rio Grande riverbed in Big Bend National Park. But disputes over water on the Mexico-Texas border go far deeper than the river. ( SCEhardt via Wikipedia ) Hosted by Ira Flatow Produced by Science Friday and WNYC Studios