Zhan Chengxiu, Li Bicheng, Chen Chuanwu, Wang Yanping
Laboratory of Island Biogeography and Conservation Biology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
Natural History Research Center, Shanghai Science and Technology Museum, Shanghai 200127, China.
Curr Zool. 2024 Mar 5;70(6):728-738. doi: 10.1093/cz/zoae006. eCollection 2024 Dec.
Nestedness is an important part of the theoretical framework of island biogeography and community ecology. However, most previous studies focused on taxonomic dimension and overlooked functional and phylogenetic nestedness. Here, we simultaneously investigated taxonomic, functional, and phylogenetic nestedness of terrestrial mammals on 39 land-bridge islands in the Zhoushan Archipelago, China. As mammals' response to the environment may depend on their body size, we performed analyses for three mammal assemblages separately: overall species, large and medium-sized species, and small species. The taxonomic nestedness was quantified by organizing the species incidence matrix, while the functional and phylogenetic nestedness were estimated by combining the similarity of their ecological traits and phylogeny. Island characteristics (island area, three isolation indices, land use intensity, and habitat diversity) and species traits (body size, litter size, habitat specificity, geographic range size, and minimum area requirement) were used as predictors of nestedness. Overall and small species were significantly nested in 3 facets of nestedness, and results supported the selective extinction, selective colonization, and habitat nestedness hypotheses. Large and medium-sized species were functionally and phylogenetically nested when matrices were ordered by increasing distance to mainland, supporting the selective colonization hypothesis. Overall, differences in nestedness and its underlying mechanisms were detected not only in 3 facets of nestedness but also in the 3 mammal assemblages. Therefore, frameworks that incorporate taxonomic, phylogenetic, and functional nestedness can contribute to a more comprehensive understanding of nestedness processes. Additionally, it also improves our ability to understand the divergent responses of mammal assemblages to the insular environment.
嵌套性是岛屿生物地理学和群落生态学理论框架的重要组成部分。然而，以往大多数研究集中在分类学维度，而忽略了功能和系统发育嵌套性。在此，我们同时调查了中国舟山群岛39个陆桥岛屿上陆生哺乳动物的分类学、功能和系统发育嵌套性。由于哺乳动物对环境的响应可能取决于其体型大小，我们分别对三类哺乳动物组合进行了分析：总体物种、大中型物种和小型物种。分类学嵌套性通过整理物种出现矩阵来量化，而功能和系统发育嵌套性则通过结合其生态特征和系统发育的相似性来估计。岛屿特征（岛屿面积、三个隔离指数、土地利用强度和栖息地多样性）和物种特征（体型大小、窝仔数、栖息地特异性、地理分布范围大小和最小面积需求）被用作嵌套性的预测因子。总体物种和小型物种在嵌套性的三个方面均呈现显著嵌套，结果支持了选择性灭绝、选择性定殖和栖息地嵌套性假说。当按照与大陆距离增加的顺序排列矩阵时，大中型物种在功能和系统发育上呈现嵌套，支持了选择性定殖假说。总体而言，不仅在嵌套性的三个方面，而且在三类哺乳动物组合中均检测到嵌套性及其潜在机制的差异。因此，纳入分类学、系统发育和功能嵌套性的框架有助于更全面地理解嵌套过程。此外，这也提高了我们理解哺乳动物组合对岛屿环境不同响应的能力。
