Accueil > Communication > Actualités scientifiques > Publications scientifiques

Publications scientifiques RSS des Publications scientifiques

Page(s) : < | 1 | ... | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | ... | 292 |

7 septembre 2018

Remoteness promotes biological invasions on islands worldwide [PNAS]

Keywords : island biogeography, alien species, isolation, island invasibility, naturalization

One of the best-known general patterns in island biogeography is the species–isolation relationship (SIR), a decrease in the number of native species with increasing island isolation that is linked to lower rates of natural dispersal and colonization on remote oceanic islands. However, during recent centuries, the anthropogenic introduction of alien species has increasingly gained importance and altered the composition and richness of island species pools. We analyzed a large dataset for alien and native plants, ants, reptiles, mammals, and birds on 257 (sub) tropical islands, and showed that, except for birds, the number of naturalized alien species increases with isolation for all taxa, a pattern that is opposite to the negative SIR of native species. We argue that the reversal of the SIR for alien species is driven by an increase in island invasibility due to reduced diversity and increased ecological naiveté of native biota on the more remote islands.

Lire la suite

7 septembre 2018

Mapping the imprint of biotic interactions on β‐diversity [Ecology Letters]

Jérôme Chave

Investigating how trophic interactions influence the β‐diversity of meta‐communities is of paramount importance to understanding the processes shaping biodiversity distribution. Here, we apply a statistical method for inferring the strength of spatial dependencies between pairs of species groups. Using simulated community data generated from a multi‐trophic model, we showed that this method can approximate biotic interactions in multi‐trophic communities based on β‐diversity patterns across groups. When applied to soil multi‐trophic communities along an elevational gradient in the French Alps, we found that fungi make a major contribution to the structuring of β‐diversity across trophic groups.(...)

Lire la suite

7 septembre 2018

Evolutionarily distinct amphibians are disproportionately lost from human‐modified ecosystems [Ecology Letters]

Keywords : diversification, extinction risk, forests, global change, grasslands, habitat loss, land conversion, phylogenetic diversity

Humans continue to alter terrestrial ecosystems, but our understanding of how biodiversity responds is still limited. Anthropogenic habitat conversion has been associated with the loss of evolutionarily distinct bird species at local scales, but whether this evolutionary pattern holds across other clades is unknown. We collate a global dataset on amphibian assemblages in intact forests and nearby human‐modified sites to assess whether evolutionary history influences susceptibility to land conversion. We found that evolutionarily distinct amphibian species are disproportionately lost when forested habitats are converted to alternative land‐uses.(...)

Lire la suite

7 septembre 2018

Life stage‐specific, stochastic environmental effects overlay density dependence in an Atlantic salmon population [Ecology of Freshwater Fish]

Keywords : density independence, environmental variability, exploitation, fisheries, long‐term data, population dynamics

Atlantic salmon populations appear to fluctuate stochastically through time. It is suspected that both density‐dependent and density‐independent factors cause these fluctuations but the relative importance of each, and the life stages at which they operate, is not well known. In this study, a long‐term data set on Atlantic salmon migrants returning to the Foyle catchment, Ireland, was used to determine the role of density‐dependent and life stage‐specific environmental factors regulating population size.A Ricker density‐dependent model showed that spawning adult population size significantly predicted variation in the resultant filial generation ; however, a large amount of variation (ca. 68%) remained unexplained.(...)

Lire la suite

7 septembre 2018

Direct and indirect effects of chemical contaminants on the behaviour, ecology and evolution of wildlife [Proceedings of the Royal Society B - Biological Sciences]

Keywords : behavioural ecology, endocrine-disrupting chemicals, predator-prey dynamics, plasticity, sublethal

Chemical contaminants (e.g. metals, pesticides, pharmaceuticals) are changing ecosystems via effects on wildlife. Indeed, recent work explicitly performed under environmentally realistic conditions reveals that chemical contaminants can have both direct and indirect effects at multiple levels of organization by influencing animal behaviour. Altered behaviour reflects multiple physiological changes and links individual- to population-level processes, thereby representing a sensitive tool for holistically assessing impacts of environmentally relevant contaminant concentrations. Here, we show that even if direct effects of contaminants on behavioural responses are reasonably well documented, there are significant knowledge gaps in understanding both the plasticity (i.e. individual variation) and evolution of contaminant-induced behavioural changes. We explore implications of multi-level processes by developing a conceptual framework that integrates direct and indirect effects on behaviour under environmentally realistic contexts.(...)

Lire la suite

Page(s) : < | 1 | ... | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | ... | 292 |