COLLABORATIVE RESEARCH: Testing Climate-Controlled Endemism in Equatorial Pangea

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Collaborative Research: Testing climate-controlled endemism in equatorial PangeaChristian A. Sidor, University of Washington (EAR-0617718)Neil J. Tabor, Southern Methodist University (EAR-0617250)This award is co-funded by NSF's Office of International Science and Engineering.ABSTRACTPaleontologists currently understand Permian terrestrial ecosystems from three main regions. The Lower Permian is best known from the classic red-bed sequence of north-central Texas and surrounding states. After a 1-2 million year gap, the Middle and Upper Permian terrestrial record picks up again in the Cis-Ural region of Russia and the Karoo Basin of South Africa. Although other minor sequences exist, this three part record (Texas, Russia, South Africa) has been the basis for the interpretation of end-Paleozoic terrestrial ecosystems for over 150 years. Importantly, however, it includes a significant geographic bias: the Texas Lower Permian was deposited at roughly the paleoequator, whereas Middle and Upper Permian Russian and South African rocks represent high-latitude basins (40 degrees N and 60 degrees S, respectively). As a consequence, interpretations of floral and faunal changes through time are confounded by latitudinal and related climatic effects. PIs research will investigate the Upper Permian strata of northern Niger because these rocks uniquely represent conditions at 10 degrees S of the paleoequator in central Pangea. Intriguingly, preliminary work has shown that an endemic tetrapod fauna is preserved in these rocks, despite being positioned halfway between those of Russia and southern Africa. This three-year study will: (1) establish the first and only continental Permian stratigraphy for West Africa, (2) use paleosol morphology and geochemistry, as well as plant fossils to test climate models for central Pangea, (3) constrain the age of the Permian rocks of Niger with bio- and chronostratigraphic data, and (4) continue to develop our understanding of this region's plant and animal fossil record. Moreover, PIs work will fill a longstanding hole in the terrestrial fossil record by providing data on a low-latitude, Upper Permian biota. Their research will also constrain future climate models by providing empirical estimates of paleotemperature and precipitation for a region where no such data currently exist. The Permian rocks of Niger are thus unique in their ability to answer questions of tetrapod biogeography and validate or refute computer-based models of paleoclimate.