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Université de Fribourg

The record of Deinotheriidae from the Miocene of the Swiss Jura Mountains (Jura Canton, Switzerland)

Gagliardi, Fanny ; Maridet, Olivier ; Becker, Damien

In: bioRxiv, 2021, p. 244061

The Miocene sands of the Swiss Jura Mountains, long exploited in quarries for the construction industry, have yielded abundant fossil remains of large mammals. Among Deinotheriidae (Proboscidea), two species, Prodeinotherium bavaricum and Deinotherium giganteum, had previously been identified in the Delémont valley, but never described. A third species, Deinotherium levius, from the locality of...

Université de Fribourg

Ranking alien species based on their risks of causing environmental impacts : A global assessment of alien ungulates

Volery, Lara ; Jatavallabhula, Divija ; Scillitani, Laura ; Bertolino, Sandro ; Bacher, Sven

In: Global Change Biology, 2021, vol. 27, no. 5, p. 1003-1016

For an efficient allocation of the limited resources to alien species management, the most damaging species should be prioritized. Comparing alien species based on their impacts is not straightforward, as the same species can cause different types and magnitudes of impacts when introduced to different contexts, making it difficult to summarize its overall impact. The Environmental Impact...

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

Dental anomaly in a middle Miocene fossil of the genus Spermophilinus (Rodentia, Sciuridae) from southern Germany

Prieto, Jérôme ; Rummel, Michael ; Peláez-Campomanes, Pablo ; Vasilyan, Davit

In: Fossil Imprint, 2020, vol. 76, no. 1, p. 174-180

The maxillary presented in this work has been excavated in the middle Miocene karst filling Petersbuch 136 (Germany, Bavaria) and shows the oldest evidence of dental anomaly in a sciurid. The aberrant morphology, probably hyperdontia or no replacement of roots of deciduous teeth, affects the area of the P3, a tooth that is generally not well documented in the Spermophilinus record.

Université de Fribourg

Automated conservation assessment of the orchid family with deep learning

Zizka, Alexander ; Silvestro, Daniele ; Vitt, Pati ; Knight, Tiffany M.

In: Conservation Biology, 2020, p. cobi.13616

International Union for Conservation of Nature (IUCN) Red List assessments are essential for prioritizing conservation needs but are resource intensive and therefore available only for a fraction of global species richness. Automated conservation assessments based on digitally available geographic occurrence records can be a rapid alternative, but it is unclear how reliable these assessments...

Université de Fribourg

Disproportionate extinction of South American mammals drove the asymmetry of the Great American Biotic Interchange

Carrillo, Juan D. ; Faurby, Søren ; Silvestro, Daniele ; Zizka, Alexander ; Jaramillo, Carlos ; Bacon, Christine D. ; Antonelli, and Alexandre

In: Proceedings of the National Academy of Sciences, 2020, vol. 117, no. 42, p. 26281–26287

The biological interchange between North and South America associated with the formation of the Isthmus of Panama is key to defining current gradients of species diversity. A major gap in our understanding of the interchange is its asymmetry, where mammals of North American origin attained higher diversity in South America than vice versa. The prevailing view is that this asymmetry resulted...

Université de Fribourg

The past and future human impact on mammalian diversity

Andermann, Tobias ; Faurby, Søren ; Turvey, Samuel T. ; Antonelli, Alexandre ; Silvestro, Daniele

In: Science Advances, 2020, vol. 6, no. 36, p. eabb2313

To understand the current biodiversity crisis, it is crucial to determine how humans have affected biodiversity in the past. However, the extent of human involvement in species extinctions from the Late Pleistocene onward remains contentious. Here, we apply Bayesian models to the fossil record to estimate how mammalian extinction rates have changed over the past 126,000 years, inferring...

Université de Fribourg

Selective extinction against redundant species buffers functional diversity

Pimiento, Catalina ; Bacon, Christine D. ; Silvestro, Daniele ; Hendy, Austin ; Jaramillo, Carlos ; Zizka, Alexander ; Meyer, Xavier ; Antonelli, Alexandre

In: Proceedings of the Royal Society B: Biological Sciences, 2020, vol. 287, no. 2020-1931, p. 20201162

The extinction of species can destabilize ecological processes. A way to assess the ecological consequences of species loss is by examining changes in functional diversity. The preservation of functional diversity depends on the range of ecological roles performed by species, or functional richness, and the number of species per role, or functional redundancy. However, current knowledge is...