to determine how the soft tissue was preserved. Lyson's work has been described in The Washington Post, The New York Times, and Good Morning America. He is also the co-founder with Harold Hanks of the Marmarth Research Foundation, located in his hometown, which provides volunteers with hands-on field and laboratory work on fossils. In 2015 Lyson appeared, as a paleontologist, in the PBS documentary film, Making North America. His quest to discover why mammals became predominant after the extinction of the dinosaurs was the subject of the PBS "Nova" series film, Rise of the Mammals. The film recounts how he and a colleague searched for mammal fossils in Colorado but found very few. Then he examined a fossil found years before by Sharon Milito, a volunteer with the Denver Museum of Nature and Science and catalogued in the museum's collection. The specimen mammal palate was found above the Cretaceous–Paleogene boundary at Corral Bluffs, Colorado, indicating it followed the extinction of the dinosaurs, and was embedded in a concretion. Lyson and his colleagues decided to hunt for fossils embedded in concretions, and made unprecedented finds documenting the rise and early evolution of mammals. References Living people 1982 births Swarthmore College alumni Yale University alumni American paleontologists Vertebrate paleontologists People from Slope County, North Dakota Scientists from North Dakota 21st-century American scientists