A Look into the Past: Fossils from the Campos Sulinos Region

Today’s Campos Sulinos have witnessed important paleogeographic, paleoclimatic, and paleoenvironmental shifts in the last 300 million years. When this history is evaluated through the perspective of fossil-bearing sedimentary rocks, it can be divided into four major events: Permian deglaciation and evolution to an alluvial plain in Pangean condition; Triassic recovery of a massive extinction and development in alluvial plains in Pangean circumstances; establishment of an aeolian system under desertic conditions during the Jurassic-Cretaceous; and the Pleistocene onset of megafauna and dominance of grassland vegetation responding to glacial and interglacial cycles. Permian biotas range from marine parareptiles, such as mesosaurs, to fully terrestrial fauna, including large herbivores such as provelosaurids, a saber-toothed herbivore, and large carnivores. Terrestrial environments were dominated by a Glossopteris Flora, with large pteridophytes and primitive gymnosperms. Triassic biota vary from near-the-water parareptiles, temnospondyls, and archosauromorphs, right after the most impressive mass extinction on our planet, to the onset of dinosaurs and the evolution of cynodonts. The Triassic also witnessed one of the main vegetation transitions in Earth’s history: environments once dominated by a Glossopteris Flora gradually became occupied by Dicroidium and Coniferous Floras. The Jurassic faunas are mostly represented by dinosaur footprints from a desert-dominated environment prior to the South America/Africa breakup. Late Pleistocene biota includes large-bodied mammals and reptiles, representatives of the so-called Pleistocene Megafauna. In addition, extant taxa are also present in the fossil record. The Late Pleistocene paleobotanic fossil record demonstrates widespread grasslands that were only slowly subject to the expansion of forests.