Instituto Patagónico para el Estudio de los Ecosistemas Continentales, Consejo Nacional de Investigaciones Científicas y Técnicas (IPEEC-CONICET), Boulevard Almirante Brown 2915, U9120ACD Puerto Madryn, Chubut, Argentina.
Instituto Patagónico para el Estudio de los Ecosistemas Continentales, Consejo Nacional de Investigaciones Científicas y Técnicas (IPEEC-CONICET), Boulevard Almirante Brown 2915, U9120ACD Puerto Madryn, Chubut, Argentina; Department of Biology, University of Konstanz, Konstanz, Germany.
Mol Phylogenet Evol. 2018 Dec;129:226-241. doi: 10.1016/j.ympev.2018.08.019. Epub 2018 Sep 8.
During the speciation process sibling lineages accumulate differences in time (e.g. genetic, morphological, and/or ecological). Phenotypic traits such as size or shape, however, could experience rapid changes or show stasis depending on their role in survival and reproduction. The clade Phymaturus patagonicus includes 26 species characterized by a conservative morphology, and all inhabit rock crevice microhabitats in arid environments. In this study we quantify levels of morphological divergence (size and shape) among the multiple species relative to interspecific molecular divergence, and show that most species have not diverged significantly in size and/or shape to permit unambiguous species diagnosis with morphological data alone. The influence of stabilizing selection for an adaptive optimum in body size and head shape was detected for 13 of the 16 variables analyzed in an Ornstein-Uhlenbeck model. The strict dependence of these species to rock-crevice microenvironments likely explains the observed morphological stasis across the many species of the Phymaturus patagonicus group.
在物种形成过程中，姊妹谱系会随着时间的推移积累差异（例如遗传、形态和/或生态）。然而，大小或形状等表型特征可能会经历快速变化或表现出停滞，具体取决于它们在生存和繁殖中的作用。Phymaturus patagonicus 分支包括 26 个物种，其特征为形态保守，并且全部栖息在干旱环境中的岩石裂缝微生境中。在这项研究中，我们量化了相对于种间分子差异的多个物种之间的形态差异（大小和形状），并表明大多数物种在大小和/或形状上没有明显分化，仅凭形态数据无法明确诊断物种。对于分析的 16 个变量中的 13 个，在奥尔森-乌伦贝克模型中检测到了对身体大小和头部形状适应最优的稳定选择的影响。这些物种对岩石裂缝微环境的严格依赖可能解释了 Phymaturus patagonicus 组中许多物种观察到的形态停滞。
