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Université de Fribourg

Enigmatic dinosaur precursors bridge the gap to the origin of Pterosauria

Ezcurra, Martín D. ; Nesbitt, Sterling J. ; Bronzati, Mario ; Vecchia, Fabio Marco Dalla ; Agnolin, Federico L. ; Benson, Roger B. J. ; Egli, Federico Brissón ; Cabreira, Sergio F. ; Evers, Serjoscha W. ; Gentil, Adriel R. ; Irmis, Randall B. ; Martinelli, Agustín G. ; Novas, Fernando E. ; Silva, Lúcio Roberto da ; Smith, Nathan D. ; Stocker, Michelle R. ; Turner, Alan H. ; Langer, Max C.

In: Nature, 2020, vol. 588, no. 2020-7838, p. 445–449

Pterosaurs were the first vertebrates to evolve powered flight1 and comprised one of the main evolutionary radiations in terrestrial ecosystems of the Mesozoic era (approximately 252–66 million years ago), but their origin has remained an unresolved enigma in palaeontology since the nineteenth century2,3,4. These flying reptiles have been hypothesized to be the close relatives of a wide...

Université de Fribourg

The rise of angiosperms pushed conifers to decline during global cooling

Condamine, Fabien L. ; Silvestro, Daniele ; Koppelhus, Eva B. ; Antonelli, Alexandre

In: Proceedings of the National Academy of Sciences, 2020, vol. 117, no. 46, p. 28867–28875

Competition among species and entire clades can impact species diversification and extinction, which can shape macroevolutionary patterns. The fossil record shows successive biotic turnovers such that a dominant group is replaced by another. One striking example involves the decline of gymnosperms and the rapid diversification and ecological dominance of angiosperms in the Cretaceous. It is...

Université de Fribourg

Fish, amphibian and reptilian assemblage from the middle Miocene locality Gračanica—Bugojno palaeolake, Bosnia and Herzegovina

Vasilyan, Davit

In: Palaeobiodiversity and Palaeoenvironments, 2020, vol. 100, no. 2, p. 437–455

This paper presents the first fossil fish, amphibian and reptilian fauna from Bosnia and Herzegovina Dinarides. The fauna of ectothermic vertebrates of the Bugojno palaeolake, dated to 15.2–14.0 Ma, composes of killifishes (Cyprinodontiformes indet.), a barb (Barbini indet. (aff. Barbus), a crocodile newt (Chelotriton sp.), a painted frog (Latonia sp.) and a crocodile (Alligatoroidea indet....

Université de Fribourg

Assessing the impact of diagenesis on foraminiferal geochemistry from a low latitude, shallow-water drift deposit

Stainbank, Stephanie ; Spezzaferri, Silvia ; Boever, Eva De ; Bouvier, Anne-Sophie ; Chilcott, Colin ; Leau, Erica S.de ; Foubert, Anneleen ; Kunkelova, Tereza ; Pichevin, Laetitia ; Raddatz, Jacek ; Rüggeberg, Andres ; D.Wright, James ; M.Yu, Siyao ; Zhang, Manlin ; Kroon, Dick

In: Earth and Planetary Science Letters, 2020, vol. 545, p. 116390

Due to their large heat and moisture storage capabilities, the tropics are fundamental in modulating both regional and global climate. Furthermore, their thermal response during past extreme warming periods, such as super interglacials, is not fully resolved. In this regard, we present high-resolution (analytical) foraminiferal geochemical (δ18O and Mg/Ca) records for the last 1800 kyr from...

Université de Fribourg

A revision of the pelomedusoid turtle Jainemys pisdurensis from the Late Cretaceous (Maastrichtian) Lameta Formation of India

Joyce, Walter G. ; Bandyopadhyay, Saswati

In: PeerJ, 2020, vol. 8, p. e9330

Background: Jainemys pisdurensis comb. nov. is an extinct pleurodiran turtle from the Late Cretaceous (Maastrichtian) of India, previously referred to Carteremys and Shweboemys. The holotype, an eroded skull, had been collected near the village of Pisdura, south of Nagpur, in Maharashtra State, while all referred shell material originates from coeval sediments exposed at the nearby village of...

Université de Fribourg

Reversed surface-mass-balance gradients on himalayan debris-covered glaciers inferred from remote sensing

Bisset, Rosie R. ; Dehecq, Amaury ; Goldberg, Daniel N. ; Huss, Matthias ; Bingham, Robert G. ; Gourmelen, Noel

In: Remote Sensing, 2020, vol. 12, no. 10, p. 1563

Meltwater from the glaciers in High Mountain Asia plays a critical role in water availability and food security in central and southern Asia. However, observations of glacier ablation and accumulation rates are limited in spatial and temporal scale due to the challenges that are associated with fieldwork at the remote, high-altitude settings of these glaciers. Here, using a...

Université de Fribourg

A new species of baenid turtle from the Early Cretaceous Lakota Formation of South Dakota

Joyce, Walter G. ; Rollot, Yann ; Cifelli, Richard L.

In: Fossil Record, 2020, vol. 23, no. 1, p. 1–13

Baenidae is a clade of paracryptodiran turtles known from the late Early Cretaceous to Eocene of North America. The proposed sister-group relationship of Baenidae to Pleurosternidae, a group of turtles known from sediments dated as early as the Late Jurassic, suggests a ghost lineage that crosses the early Early Cretaceous. We here document a new species of paracryptodiran turtle, Lakotemys...

Université de Fribourg

First fossil frog from Antarctica: implications for Eocene high latitude climate conditions and Gondwanan cosmopolitanism of Australobatrachia

Mörs, Thomas ; Reguero, Marcelo ; Vasilyan, Davit

In: Scientific Reports, 2020, vol. 10, p. 5051

Cenozoic ectothermic continental tetrapods (amphibians and reptiles) have not been documented previously from Antarctica, in contrast to all other continents. Here we report a fossil ilium and an ornamented skull bone that can be attributed to the Recent, South American, anuran family Calyptocephalellidae or helmeted frogs, representing the first modern amphibian found in Antarctica. The two bone...

Università della Svizzera italiana

A novel interaction between the TLR7 and a colchicine derivative revealed through a computational and experimental study

Gentile, Francesco ; Deriu, Marco A. ; Barakat, Khaled ; Danani, Andrea ; Tuszynski, Jack

In: Pharmaceuticals, 2018, vol. 11, no. 1, p. 22

The Toll-Like Receptor 7 (TLR7) is an endosomal membrane receptor involved in the innate immune system response. Its best-known small molecule activators are imidazoquinoline derivatives such as imiquimod (R-837) and resiquimod (R-848). Recently, an interaction between R-837 and the colchicine binding site of tubulin was reported. To investigate the possibility of an interaction between...

Université de Fribourg

Late Jurassic theropod dinosaur bones from the Langenberg Quarry (Lower Saxony, Germany) provide evidence for several theropod lineages in the central European archipelago

Evers, Serjoscha W. ; Wings, Oliver

In: PeerJ, 2020, vol. 8, p. e8437

Marine limestones and marls in the Langenberg Quarry provide unique insights into a Late Jurassic island ecosystem in central Europe. The beds yield a varied assemblage of terrestrial vertebrates including extremely rare bones of theropod from theropod dinosaurs, which we describe here for the first time. All of the theropod bones belong to relatively small individuals but represent a wide...