An article published in the journal “American Museum Novitates” reports the description of first traces of vertebrate fossils probably dating back to 8-9 million years ago, in the Neogene period, which include rhinos. A team of researchers led by Jaelyn Eberle of the Natural History Museum of the University of Colorado at Boulder subjected the fossils to sophisticated tests such as the electron microscope to examine their characteristics and identify if not the species at least the family they belong to. This made it possible to establish that these were, for example, fragments of turtle and tortoise shell and rhino teeth.