| Autor: |
Espel D; CNRS, ECOBIO (Ecosystèmes, Biodiversité, Evolution), UMR 6553, University of Rennes, F-35000 Rennes, France., Coux C; CNRS, Inserm, CHU Lille, Institut Pasteur Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, University of Lille, F-59000 Lille, France.; CEFE, University of Montpellier, CNRS, EPHE, IRD, F-34000 Montpellier, France., Pertierra LR; Department of Plant and Soil Sciences, University of Pretoria, Pretoria 0002, South Africa., Eymar-Dauphin P; CNRS, LEHNA (Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés), UMR 5023, University of Lyon 1, F-69100 Villeurbanne, France., Lembrechts JJ; Research Group Plants and Ecosystems (PLECO), University of Antwerp, 2610 Antwerpen, Belgium., Renault D; CNRS, ECOBIO (Ecosystèmes, Biodiversité, Evolution), UMR 6553, University of Rennes, F-35000 Rennes, France. |
| Abstrakt: |
Phenotypic plasticity can favor the emergence of different morphotypes specialized in specific ranges of environmental conditions. The existence of intraspecific partitioning confers resilience at the species scale and can ultimately determine species survival in a context of global changes. Amblystogenium pacificum is a carabid beetle endemic to the sub-Antarctic Crozet Islands, and it has two distinctive morphotypes based on body coloration. For this study, A. pacificum specimens of functional niches were sampled along an altitudinal gradient (as a proxy for temperature), and some morphological and biochemical traits were measured. We used an FAMD multivariate analysis and linear mixed-effects models to test whether these traits were related to morphotype, altitude, and sexual dimorphism. We then calculated and compared the functional niches at different altitudes and tested for niche partitioning through a hypervolume approach. We found a positive hump-shaped correlation between altitude and body size as well as higher protein and sugar reserves in females than in males. Our functional hypervolume results suggest that the main driver of niche partitioning along the altitudinal gradient is body size rather than morphotype or sex, even though darker morphotypes tended to be more functionally constrained at higher altitudes and females showed limited trait variations at the highest altitude. |
