Gizmodo writes that University of Arizona researchers reported an 8.8 million year Cardiatherium tooth from Chile's Bahía Inglesa beds, a find that implies wetter late Miocene conditions on a coast now treated as hyper-arid for tens of millions of years. University of Arizona News, covering the same paper, says the tooth is Chile's first and oldest coastal capybara find and that no capybaras live in the country today.
Gizmodo said researchers at the University of Arizona and others reported a fossilized capybara tooth from Chile dated to roughly 8.8 million years, assigned to the extinct genus Cardiatherium. University of Arizona News said the specimen came from El Morro in the Bahía Inglesa Formation, in sediments deposited in a shallow marine setting between about 10 and 7 million years ago, and that Chile has no living capybaras.[1], [2]
Gizmodo wrote that the Atacama is often treated as having stayed hyper-arid for at least about 40 million years, while capybaras need water and wetland plants. University of Arizona News said the same contrast: capybaras are obligate semiaquatic herbivores east of the Andes, and the tooth is offered as Chile's first and oldest coastal capybara find, currently in press at Scientific Reports.[1], [2]
Scientific Reports describes a partial left M3, MPC 3000, assigned to Cardiatherium at about 8.8 million years, with pedogenic-carbonate isotopes pointing to C3-dominated vegetation and phytoliths of palms and dicots. Gizmodo separately noted palms and other flowering plants in the same interval. The paper argues that occurrence implies ecological connectivity between eastern wetlands and the Pacific margin, either across the Andes or by a northern westward-draining route.[3], [1]
