46 research outputs found

    Diverse New Microvertebrate Assemblage from the Upper Triassic Cumnock Formation, Sanford Subbasin, North Carolina, USA

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    The Moncure microvertebrate locality in the Cumnock Formation, Sanford sub-basin, North Carolina, dramatically increases the known Late Triassic age vertebrate assemblage from the Deep River Basin. The 50,000 recovered microvertebrate fossils include osteichthyans, amphibians, and numerous lepidosauromorph, archosauriform, and synapsid amniotes. Actinopterygian fossils consist of thousands of scales, teeth, skull, and lower jaw fragments, principally of redfieldiids and semionotids. Non-tetrapod sarcopterygians include the dipnoan Arganodus sp., the first record of lungfish in the Newark Supergroup. Temnospondyls are comparatively rare but the preserved centra, teeth, and skull fragments probably represent small (juvenile) metoposaurids. Two fragmentary teeth are assigned to the unusual reptile Colognathus obscurus (Case). Poorly preserved but intriguing records include acrodont and pleurodont jaw fragments tentatively assigned to lepidosaurs. Among the archosauriform teeth is a taxon distinct from R. callenderi that we assign to Revueltosaurus olseni new combination, a morphotype best assigned to cf. Galtonia, the first Newark Supergroup record of Crosbysaurus sp., and several other archosauriform tooth morphotypes, as well as grooved teeth assigned to the recently named species Uatchitodon schneideri. Synapsids represented by molariform teeth include both "traversodontids" assigned to aff. Boreogomphodon and the "dromatheriid" Microconodon. These records are biogeographically important, with many new records for the Cumnock Formation and/or the Newark Supergroup. In particular, Colognathus, Crosbysaurus, and Uatchitodon are known from basins of Adamanian age in the southwestern U.S.A. These new records include microvertebrate taxa more typical of non-Newark basins (abundant archosauriforms, temnospondyls, lungfish) as well as more typical Newark osteichthyans and synapsid-rich faunal elements

    Small Theropod Teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and Their Implications for Understanding Latest Cretaceous Dinosaur Evolution

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    Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs. Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns. We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian - Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas. The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately coeval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species. A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction

    A last cup of tea with Gotthard Richter (1924–2021)

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    Aufbau von regionalen Schülerforschungszentren: Berichte und Praxisempfehlungen

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    Angesichts des sich verschärfenden Fachkräftemangels ist es wichtig, die vorhandenen Begabungspotenziale noch wirkungsvoller zu identifizieren und auszuschöpfen. Vor allem im Bereich von Mathematik, Informatik, Naturwissenschaft und Technik (MINT) erweist es sich als zielführend, künftig stärker auf forschendes Lernen zu setzen. Dieser pädagogische Ansatz wird auf vorbildliche Weise an Schülerforschungszentren verwirklicht. Aufgrund der Chancen für die Nachwuchsförderung, die mit diesen außerschulischen MINT-Bildungszentren verbunden sind, haben der Deutsche Industrie- und Handelskammertag (DIHK), die IHK Darmstadt, LernortLabor - Bundesverband der Schülerlabore e. V. und die Stiftung Jugend forscht e. V. gemeinsam einen Leitfaden für den „Aufbau regionaler Schülerforschungszentren“ erarbeitet. Die neue Publikation ist als Best Practice-Handreichung konzipiert und soll vor allem regionale Entscheidungsträger in die Lage versetzen, auf diesem Feld selbst aktiv zu werden und den begonnenen Prozess der Gründung von Schülerforschungszentren weiter voranzutreiben. Vom Konzept, über Aufbau und Finanzierung bis hin zur Didaktik – Bildungsexperten und die „Macher“ bereits bestehender Schülerforschungszentren berichten in dem Leitfaden über ihre Erfahrungen bei der Gründung dieser Freizeitlernorte. Die Publikation, die aus einer gemeinsamen Fachtagung unter Führung des DIHK hervorgegangen ist, umfasst auch eine umfangreiche Dokumentation einschließlich eines Pools von Kontaktadressen für weiterführende Informationen

    Potentials and limits of Morphometry in the understanding of Squamate Osteological Structures

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