Data and code from: Re-assessing niche partitioning in MacArthur's Warblers: foraging behavior, morphology, and diet differentiation in a phylogenetic context

Due in large part to MacArthur’s classic 1958 paper, wood warblers in the family Parulidae are textbook exemplars of species competition and niche partitioning. The conventional wisdom suggests that subtle differences in foraging behavior are the principal means by which these nearly morphologically indistinguishable species are able to co-occur and avoid extinction. Yet, MacArthur’s study was in fact quite limited in scale, and he said little about the relevance of evolution to the study system. Here, we reassess MacArthur’s conclusions across an expanded set of syntopic warbler species in a forest in northern New York. We combine morphometrics, quantitative foraging data, and fecal metabarcoding—a direct measure of warbler diet—to study competition and niche partitioning in an evolutionary framework. We find close relationships between morphology and foraging behavior, but little connection between warbler ecomorphology and the 2,237 invertebrate taxa detected in their diets. Instead, diet remains phylogenetically conserved—closely related warblers eat similar suites of invertebrates, regardless of where they forage. Finally, we present evidence that these species not only partition niche space in the present day, but that competition has shaped their behaviors over evolutionary time. Here we provide the code and data associated with this project. Raw sequencing data can be accessed at the NCBI SRA under Bioproject PRJNA889412.得益于麦克阿瑟1958年的经典论文，森莺科（Parulidae）林莺类鸟类已成为物种竞争与生态位分化的经典教学范例。学界普遍认为，取食行为上的细微差异是这些形态近乎难以区分的物种得以同域共存并避免灭绝的核心机制。然而，麦克阿瑟的该项研究实际尺度十分有限，且几乎未提及演化与该研究系统的关联性。本研究针对纽约北部某森林中新增的一批同域林莺物种，重新评估了麦克阿瑟的相关结论。本研究结合形态测量学数据、定量取食行为数据与粪便宏条形码技术（fecal metabarcoding，可直接反映林莺的食物组成），在演化框架下探究物种竞争与生态位分化问题。研究发现，形态与取食行为间存在紧密关联，但林莺的生态形态学特征与其饮食中检测到的2237种无脊椎动物类群之间几乎不存在关联。与之相反，其饮食具有系统发育保守性：亲缘关系较近的林莺会取食相似类群的无脊椎动物，与其取食位置无关。最后，本研究提供证据表明，这些林莺物种不仅在当下存在生态位空间分化，且竞争作用在演化历程中塑造了它们的取食行为。本研究附带提供了本项目相关的代码与数据集。原始测序数据可于美国国家生物技术信息中心序列读取档案（NCBI SRA）中获取，对应的生物项目编号为PRJNA889412。