Fossils from ancient Fossil Lake give insight into the wildlife in Wyoming 52 million years ago By Tracie Binkerd Photos courtesy of the National Park Service Few places showcase fossils as well as the ancient Fossil Lake of the Green River Formation near Kemmerer. The photograph shows several fossils of Cockerellites liops, which is one of seven species of perch-like fish found there. (Photo by National Park Service) Wyoming Wildlife | 31