To gaze upon a full T. rex skeleton is to be transported back in time. Dinosaur fossils are key to understanding what these prehistoric creatures looked like, how they moved, and where they lived.But there’s one type of dinosaur fossil that’s sometimes overlooked: poop. Its scientific name is coprolite. These fossilized feces are rarer than their boney counterparts, but they’re key to better understanding dino diets and ecosystems.This all raises an important question: How scientists know if something is fossilized dino poop or just a rock?At Science Friday Live in Boulder, Ira talks with Dr. Karen Chin, paleontologist and professor of geological sciences at the University of Colorado, Boulder to answer that question and much more.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.