Université de Fribourg

New species, revision, and phylogeny of Ronzotherium Aymard, 1854 (Perissodactyla, Rhinocerotidae)

Tissier, Jérémy ; Antoine, Pierre-Olivier ; Becker, Damien

In: European Journal of Taxonomy, 2021, vol. 753, p. 1-80

Ronzotherium is one of the earliest Rhinocerotidae in Europe, which first appeared just after the Eocene/Oligocene transition (Grande Coupure), and became extinct at the end of the Oligocene. It is a large-sized rhinocerotid, with a special position in the phylogeny of this group, as being one of the earliest-branching true Rhinocerotidae. However, its intra-generic systematics has never been...

Université de Fribourg

New data on early Oligocene dormice (Rodentia, Gliridae) from southern Europe : Phylogeny and diversification of the family

Lu, Xiaoyu ; Costeur, Loïc ; Hugueney, Marguerite ; Maridet, Olivier

In: Journal of Systematic Palaeontology, 2021, p. 1-21

Rodents of the extant family Gliridae, commonly called dormice, are common in European faunas since the early Eocene. Here we study for the first time specimens from St-Martin-de-Castillon C (France, early Oligocene) previously reported as Gliravus aff. majori and Pseudodryomys aff. fugax. We now refer them to Butseloglis tenuis and Microdyromys misonnei. Besides the French material, new...

Université de Fribourg

New material of Epiaceratherium and a new species of Mesaceratherium clear up the phylogeny of early Rhinocerotidae (Perissodactyla)

Tissier, Jérémy ; Antoine, Pierre-Olivier ; Becker, Damien

In: Royal Society Open Science, 2020, vol. 7, no. 7, p. 200633

Reduction of the anterior dentition (i.e. incisors and canines) is a major adaptative trait of the Rhinocerotidae among Perissodactyla. However, the corresponding evolutionary sequence was lacking a robust phylogenetic frame to support it thus far. Here, we describe a new Oligocene species of Rhinocerotinae, Mesaceratherium sp. nov. from the Swiss locality of Bumbach (MP25 reference level)....

Université de Fribourg

Components of phylogenetic signal in antagonistic and mutualistic networks.

Rohr, Rudolf P. ; Bascompte, Jordi

In: The American Naturalist, 2014, vol. 184, no. 5, p. 556–564

Recent studies have shown a phylogenetic signal in the structure of ecological networks, making the point that evolutionary history is important in explaining network architecture. However, this previous work has focused on either antagonistic (i.e., predator-prey) or mutualistic networks and has used different methodologies. Thus, a comparative assessment of both the frequency and the...

Université de Fribourg

Explaining the variation in impacts of non-native plants on local-scale species richness: the role of phylogenetic relatedness

Vilà, Montserrat ; Rohr, Rudolf P. ; Espinar, José L. ; Hulme, Philip E. ; Pergl, Jan ; Roux, Johannes J. Le ; Schaffner, Urs ; Pyšek, Petr

In: Global Ecology and Biogeography, 2014, p. -

Aim: To assess how the magnitude of impacts of non-native plants on species richness of resident plants and animals varies in relation to the traits and phylogenetic position of the non-native as well as characteristics of the invaded site.Location: Global.Methods: Meta-analysis and phylogenetic regressions based on 216 studies were used to examine the effects of 96 non-native plant species on...

Université de Fribourg

Modeling food webs: exploring unexplained structure using latent traits

Rohr, Rudolf Philippe ; Scherer, Heike ; Kehrli, Patrik ; Mazza, Christian ; Bersier, Louis-Félix

In: The American Naturalist, 2010, vol. 176, no. 2, p. 170-177

Several stochastic models have tried to capture the architecture of food webs. This approach is interesting, but it is limited by the fact that different assumptions can yield similar results. To overcome this limitation, we develop a purely statistical approach. Body size in terms of an optimal ratio between prey and predator is used as explanatory variable. In 12 observed food webs, this model...

Université de Fribourg

New skeleton from the early Oligocene of Germany indicates a stem-group position of diomedeoidid birds

De Pietri, Vanesa L. ; Berger, Jean-Pierre ; Pirkenseer, Claudius ; Scherler, Laureline ; Mayr, Gerald

In: Acta Palaeontologica Polonica, 2010, vol. 55, no. 1, p. 23-34

We report a new specimen of the extinct procellariiform species Diomedeoides brodkorbi (Aves, Diomedeoididae) from the early Oligocene (Rupelian) of Rheinweiler in southwestern Germany. The well−preserved partial skeleton allows the recognition and reassessment of new osteological details that bear on the phylogenetic affinities of diomedeoidids. The presence on the coracoid of a deeply...

Université de Fribourg

A basal sauropod dinosaur from the Early Jurassic of Morocco

Allain, Ronan ; Aquesbi, Najat ; Dejax, Jean ; Meyer, Christian ; Monbaron, Michel ; Montenat, Christian ; Richir, Philippe ; Rochdy, Mohammed ; Russell, Dale ; Taquet, Philippe

In: Comptes Rendus Palevol, 2004, vol. 3(3), p. 199

Continental strata of Early Jurassic age are seldom exposed, and little is known of the history of sauropod dinosaurs prior to the Middle Jurassic radiation of neosauropods. Well-preserved skeletons and skulls have not been recovered from strata older than the Middle Jurassic. Here we report, in the Early Jurassic of the Moroccan High Atlas, the discovery of the skeleton, including cranial...