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Abstract：
The topographical, geological, climatic and biodiversity complexity of Mesoamerica has made it a primary research focus. The Mesoamerican highlands is a region with particularly high species richness and within-species variation. The Cinnamon-bellied Flowerpiercer, Diglossa baritula (Wagler, 1832), is a species endemic to the Mesoamerican highlands, with three allopatric subspecies currently recognized. To characterize divergence within this species, we integrated genomics, morphology, coloration and ecological niche modeling approaches, obtained from sampling individuals across the entire geographic distribution of the species. Our results revealed a clear genomic divergence between the populations to the east versus the west of the Isthmus of Tehuantepec. In contrast to the genomic results, morphology and coloration analyses showed intermediate levels of differentiation, indicating that population groups within D. baritula have probably been under similar selective pressures. Our morphology results indicated that the only sexually dimorphic morphological variable is the wing chord, with males having a longer wing chord than females. Finally, ecological data indicated that there are differences in ecological niche within D. baritula. Our data suggest that D. baritula could contain two or more incipient species at the intermediate phase of the speciation continuum. These results highlight the importance of the geographical barrier of the Isthmus of Tehuantepec and Pleistocene climatic events in driving isolation and population divergence in D. baritula. The present investigation illustrates the speciation potential of the D. baritula complex and the capacity of Mesoamerican highlands to create cryptic biodiversity and endemism.
摘要：
地形,地质,中美洲的气候和生物多样性复杂性使其成为主要研究重点。中美洲高地是一个物种丰富度和物种内变异特别高的地区。肉桂腹的花洞,Diglossabaritula(Wagler,1832),是中美洲高地特有的物种，目前公认有三个异型亚种。为了描述这个物种内部的差异，我们整合了基因组学，形态学,着色和生态位建模方法，从整个物种地理分布中对个体进行采样获得。我们的结果表明，Tehuantepec地峡东部和西部的种群之间存在明显的基因组差异。与基因组结果相反，形态学和着色分析显示中等分化水平，表明Baritula中的人群可能处于类似的选择压力下。我们的形态学结果表明，唯一的性二态形态变量是翼弦，雄性的翼弦比雌性长。最后,生态数据表明，Baritula内部的生态位存在差异。我们的数据表明，在物种形成连续体的中间阶段，D.baritula可能包含两个或多个初期物种。这些结果突显了Tehuantepec地峡的地理屏障和更新世气候事件在驱动D.baritula的隔离和种群差异中的重要性。本调查说明了D.baritula复合体的物种形成潜力以及中美洲高地创造神秘生物多样性和特有性的能力。
