Data from: Exploring the nature of ecological specialization in a coral reef fish community: morphology, diet, and foraging microhabitat use

Patterns of ecological specialization offer invaluable information about ecosystems. Yet, specialization is rarely quantified across several ecological niche axes and variables beyond the link between morphological and dietary specialization have received little attention. Here, we provide a quantitative evaluation of ecological specialization in a coral reef fish assemblage (f. Acanthuridae) along one fundamental and two realized niche axes. Specifically, we examined ecological specialization in 10 surgeonfish species with regards to morphology and two realized niche axes associated with diet and foraging microhabitat utilization using a recently developed multidimensional framework. We then investigated the potential relationships between morphological and behavioural specialization. These relationships differed markedly from the traditional ecomorphological paradigm. While morphological specialization showed no relationship with dietary specialization, it exhibited a strong relationship with foraging microhabitat specialization. However, this relationship was inverted: species with specialized morphologies were microhabitat generalists, whereas generalized morphotypes were microhabitat specialists. Interestingly, this mirrors relationships found in plant–pollinator communities and may also be applicable to other ecosystems, highlighting the potential importance of including niche axes beyond dietary specialization into ecomorphological frameworks. On coral reefs, it appears that morphotypes commonly perceived as most generalized may, in fact, be specialized in exploiting flat and easily accessible microhabitats.

生态特化模式可为生态系统研究提供极具价值的科学信息。然而，当前鲜有研究从多条生态位轴量化物种的特化程度，且除形态特化与食性特化间的关联外，其他变量间的关联尚未得到充分关注。本研究依托新近提出的多维分析框架（multidimensional framework），针对刺尾鱼科（Acanthuridae）的珊瑚礁鱼类类群，沿1条基础生态位轴与2条现实生态位轴开展生态特化的定量评估。具体而言，我们围绕形态特征，以及与食性、觅食微生境利用相关的2条现实生态位轴，对10种刺尾鱼（surgeonfish）的生态特化情况展开了考察。随后，我们分析了形态特化与行为特化间的潜在关联，结果与传统生态形态学范式（ecomorphological paradigm）存在显著差异。尽管形态特化与食性特化之间未呈现显著相关性，但与觅食微生境特化却存在较强的关联。然而这一关联方向恰好相反：具有特化形态的物种实为微生境泛化者，而形态泛化的物种反而为微生境特化者。有趣的是，这一现象与植物-传粉者群落（plant–pollinator communities）中发现的关联模式高度相似，且或许可推广至其他生态系统，这也凸显了在生态形态学研究框架中纳入食性以外的生态位轴的重要意义。在珊瑚礁生态系统中，通常被认为形态最为泛化的类群，实则可能特化利用平坦且易于进入的微生境。