Catopsbaatar
Catopsbaatar is a genus of multituberculate, an extinct order of rodent-like mammals. It lived in what is now Mongolia during the late Campanian age of the Late Cretaceous Period, about 72 million years ago. The first fossils were collected in the early 1970s, and the animal was named as a new species of the genus "Djadochtatherium " in 1974, "D. catopsaloides". The specific name refers to the animal's similarity to the genus "Catopsalis". The species was moved to the genus "Catopsalis" in 1979, and received its own genus ("Catopsbaatar", Greek and Mongolian for "visible hero") in 1994. Five skulls, one molar, and one skeleton with a skull are known; the latter is the genus' most complete specimen. "Catopsbaatar" was a member of the family Djadochtatheriidae.
Tyson Spring Cave
In 2008, Ackerman and several other cavers began to excavate a side passage in the cave and discovered an ancient bone. He brought the bone to David Mather at the St. Paul History Center, who was able to identify it as part of an elk or moose, but was unable to identify the exact species. The bone was then sent to the Illinois State Museum's assistant curator, Chris Widga. The Illinois State Museum identified the ancient bone to be a prehistoric Stag-Moose (Cervalces Scotti) antler, which is the first record of a stag-moose in Minnesota. Shortly thereafter, Chris Widga was examining the discovery site of the antler when he discovered the skull to an ancient saber-tooth cat (Homotherium serum), which is the first record of a saber-tooth cat in the Great Lakes region. The nearest discovery of a saber-tooth cat is in northern Arkansas. The Rafter Radiocarbon National Isotope Center in New Zealand used radiocarbon dating to identify that the Saber-tooth cat lived approximately 27,000 years ago. Paleontologists were stunned when Penn State lab successfully amplified and sequenced DNA from the extinct saber-tooth cat. Since the discovery of the stag-moose antler and the saber-tooth cat skull, more than 175 ancient bones dating between 27,590 and 26,200 years old have been found in Tyson Spring Cave and Bat River Cave.