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Track-event theory of cell survival with second-order repair

Besserer, Jürgen ; Schneider, Uwe

In: Radiation and Environmental Biophysics, 2015, vol. 54, no. 2, p. 167-174

Université de Fribourg

Climate change and alpine screes: no future for glacial relict papaver occidentale (papaveraceae) in western prealps

Fragnière, Yann ; Pittet, Loïc ; Clément, Benoît ; Bétrisey, Sébastien ; Gerber, Emanuel ; Ronikier, Michał ; Parisod, Christian ; Kozlowski, Gregor

In: Diversity, 2020, vol. 12, no. 9, p. 346

Glacial relicts, especially those with very narrow habitat requirements, are particularly affected by global warming. We considered Papaver occidentale, a glacial relict endemic to the Western Prealps, belonging to the alpine poppy complex (P. alpinum aggr.), as a model taxon to study the actual status and potential future distribution of species restricted to particular microrefugia. For...

Université de Fribourg

Parasite‐driven replacement of a sexual by a closely related asexual taxon in nature

Lohr, Jennifer N. ; Haag, Christoph R.

In: Ecology, 2020, vol. 101, no. 10, p. -

Asexual species are thought to suffer more from coevolving parasites than related sexuals. Yet a variety of studies do not find the patterns predicted by theory. Here, to shine light on this conundrum, we investigate one such case of an asexual advantage in the presence of parasites. We follow the frequency dynamics of sexual and asexual Daphnia pulex in a natural pond that was initially...

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...

Université de Fribourg

Does being assigned to a low school track negatively affect psychological adjustment?

Müller, Christoph Michael ; Hofmann, Verena

In: School Effectiveness and School Improvement, 2016, vol. 27, p. 95-115

Previous research suggests that the 1st year in secondary school for some students goes hand in hand with an increase in adjustment difficulties. One factor that might influence this process on an individual, compositional, and institutional level is the academic track a student attends. It was hypothesized that being assigned to a lowqualifying track predicts a stronger increase in...

Université de Fribourg

Species delimitation in the East Asian species of the relict tree genus Zelkova (Ulmaceae): A complex history of diversification and admixture among species

Naciri, Yamama ; Christe, Camille ; Bétrisey, Sébastien ; Song, Yi-Gang ; Deng, Min ; Garfì, Giuseppe ; Kozlowski, Gregor

In: Molecular Phylogenetics and Evolution, 2019, vol. 134, p. 172–185

Zelkova species, trees of the elm family (Ulmaceae), are part of the Cenozoic relict flora. In western Eurasia, the genus comprises three species that are restricted to disjunct areas (Z. sicula on Sicily, Z. abelicea on Crete and Z. carpinifolia in Transcaucasia). The situation is different in East Asia, where three species (Z. serrata, Z. schneideriana and Z. sinica) have at least partly...