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Université de Fribourg

Benefits from living together? Clades whose species use similar habitats may persist as a result of eco-evolutionary feedbacks

Prinzing, Andreas ; Ozinga, Wim A. ; Brändle, Martin ; Courty, Pierre-Emmanuel ; Hennion, Françoise ; Labandeira, Conrad ; Parisod, Christian ; Pihain, Mickael ; Bartish, Igor V.

In: New Phytologist, 2017, vol. 213, no. 1, p. 66–82

Recent decades have seen declines of entire plant clades while other clades persist despite changing environments. We suggest that one reason why some clades persist is that species within these clades use similar habitats, because such similarity may increase the degree of co-occurrence of species within clades. Traditionally, co- occurrence among clade members has been suggested to be...

Université de Fribourg

Is hybridization driving the evolution of climatic niche in Alyssum montanum

Arrigo, Nils ; La Harpe, Marylaure de ; Litsios, Glenn ; Zozomová-Lihová, Judita ; Španiel, Stanislav ; Marhold, Karol ; Barker, Michael S. ; Alvarez, Nadir

In: American Journal of Botany, 2016, p. -

PREMISE OF THE STUDY: After decades of interest, the contribution of hybridization to ecological diversification remains unclear. Hybridization is a potent source of novelty, but nascent hybrid lineages must overcome reproductive and ecological competition from their parental species. Here, we assess whether hybrid speciation is advantageous over alternative modes of speciation, by comparing...

Université de Fribourg

Plant neighbours rather than soil biota determine impact of an alien plant invader

Sun, Yan ; Müller-Schärer, Heinz ; Schaffner, Urs

In: Functional Ecology, 2014, vol. 28, no. 6, p. 1545–1555

1. Various factors have been shown contributing to the ecosystem impact of invasive alien plants, but their relative importance remains unclear. We focused on the effects of neighbouring plant community and soil biota as these biotic factors have been repeatedly put forward to explain invasion success (e.g. as components of the novel weapons and of the biotic release hypothesis).2. To assess...

Université de Fribourg

Potential contribution of natural enemies to patterns of local adaptation in plants

Crémieux, Lisèle ; Bischoff, Armin ; Šmilauerová, Majka ; Lawson, Clare S. ; Mortimer, Simon R. ; Doležal, Jiří ; Lanta, Vojtěch ; Edwards, Andrew R. ; Brook, Alex J. ; Tscheulin, Thomas ; Macel, Mirka ; Lepš, Jan ; Müller-Schärer, Heinz ; Steinger, Thomas

In: New Phytologist, 2008, vol. 180, no. 2, p. 524 - 533

Genetic differentiation among plant populations and adaptation to local environmental conditions are well documented. However, few studies have examined the potential contribution of plant antagonists, such as insect herbivores and pathogens, to the pattern of local adaptation.Here, a reciprocal transplant experiment was set up at three sites across Europe using two common plant species, Holcus...

Université de Fribourg

The importance of plant provenance and genotypic diversity of seed material used for ecological restoration

Bischoff, Armin ; Steinger, Thomas ; Müller-Schärer, Heinz

In: Restoration Ecology, 2009///doi:10.1111/j.1526-100X.2008.00454.x

The increased translocation of plant species for biodiversity restoration and habitat creation has provoked a debate on provenance and genotypic diversity of the used plant material. Nonlocal provenances are often not adapted to the local environmental conditions, and low population genotypic diversity may result in genetic bottlenecks hampering successful establishment. We tested provenance...

Université de Fribourg

Predicting adaptive evolution under elevated atmospheric CO₂ in the perennial grass Bromus erectus

Steinger, Thomas ; Stephan, André ; Schmid, Bernhard

In: Global Change Biology, 2007, vol. 13, no. 5, p. 1028-1039

Increasing concentrations of CO₂ in the atmosphere are likely to affect the ecological dynamics of plant populations and communities worldwide, yet little is known about potential evolutionary consequences of high CO₂. We employed a quantitative genetic framework to examine how the expression of genetic variation and covariation in fitness-related traits, and thus, the evolutionary potential...

Université de Fribourg

Minority games with heterogeneous timescales

Mosetti, Giancarlo ; Challet, Damien ; Zhang, Yi-Cheng

In: Physica A: Statistical Mechanics and its Applications, 2006, vol. 365, no. 2, p. 529-542

Minority games where groups of agents remember, react or incorporate information with different timescales are investigated. We support our findings by analytical arguments whenever possible.

Université de Fribourg

Detecting local adaptation in widespread grassland species – the importance of scale and local plant community

Bischoff, Armin ; Crémieux, Lisèle ; Smilauerova, Marie ; Lawson, Clare S. ; Mortimer, Simon R. ; Dolezal, Jiri ; Lanta, Vojtech ; Edwards, Andrew R. ; Brook, Alex J. ; Macel, Mirka ; Leps, Jan ; Steinger, Thomas ; Müller-Schärer, Heinz

In: Journal of Ecology, 2006, vol. 94, p. 1130-1142

1 Adaptation of plant populations to local environments has been shown in many species but local adaptation is not always apparent and spatial scales of differentiation are not well known. In a reciprocal transplant experiment we tested whether: (i) three widespread grassland species are locally adapted at a European scale; (ii) detection of local adaptation depends on competition with the...

Université de Fribourg

Seed provenance matters — Effects on germination of four plant species used for ecological restoration

Bischoff, Armin ; Vonlanthen, Beatrice ; Steinger, Thomas ; Müller-Schärer, Heinz

In: Basic and Applied Ecology, 2006, vol. 7, no. 4, p. 347-359

The use of local seed provenances is often recommended in restoration and habitat creation because they are thought to be better adapted to local habitat conditions. However, spatial scales and the degree of population differentiation are not well known and germination is often not included in comparisons between provenances. We analysed germination as a key trait of plant development in five...

Université de Fribourg

Mathematical analysis of competition between sensory ganglion cells for neurotrophic factor in the skin

Kohli, R. ; Gabriel, Jean-Pierre ; Clarke, P.G.H.

In: Mathematical Biosciences, 2004, vol. 191, p. 207

A model is presented of competition between sensory axons for trophic molecules (e.g. a neurotrophin such as NGF), produced in a region of skin small enough to permit their free diffusion throughout it; e.g., a touch dome, or a vibrissal follicle hair sinus. The variables specified are the number of high affinity trophic factor receptors per axon terminal and the concentration of trophic factor...