Espel Diane, Coux Camille, Pertierra Luis R, Eymar-Dauphin Pauline, Lembrechts Jonas J, Renault David
CNRS, ECOBIO (Ecosystèmes, Biodiversité, Evolution), UMR 6553, University of Rennes, F-35000 Rennes, France.
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.
Insects. 2023 Jan 25;14(2):123. doi: 10.3390/insects14020123.
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. is a carabid beetle endemic to the sub-Antarctic Crozet Islands, and it has two distinctive morphotypes based on body coloration. For this study, 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.
表型可塑性有利于在特定环境条件范围内出现不同的形态型。种内划分的存在赋予了物种尺度上的恢复力，并最终决定了在全球变化背景下物种的生存。是一种南极克罗泽群岛特有的步甲科甲虫，它有两种基于体色的独特形态型。在本研究中，沿着海拔梯度（作为温度的替代指标）对功能生态位的标本进行了采样，并测量了一些形态和生化特征。我们使用了FAMD多变量分析和线性混合效应模型来测试这些特征是否与形态型、海拔和两性异形有关。然后，我们计算并比较了不同海拔高度的功能生态位，并通过超体积方法测试了生态位划分情况。我们发现海拔与体型之间呈正驼峰形相关，且雌性的蛋白质和糖储备高于雄性。我们的功能超体积结果表明，沿海拔梯度生态位划分的主要驱动因素是体型，而非形态型或性别，尽管较深的形态型在较高海拔处往往受到更多功能限制，且雌性在最高海拔处的性状变化有限。
