Ecological contributions to body shape evolution in salamanders of the genus Eurycea (Plethodontidae)
Ecological contributions to body shape evolution in salamanders of the genus Eurycea (Plethodontidae)
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DOI：
10.1371/journal.pone.0216754
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发表时间：
2019-05-15
期刊：
影响因子：
3.7
通讯作者：
Taylor, Douglas R.
中科院分区：
文献类型：
--
作者：
Edgington, Hilary A.;Taylor, Douglas R.
背景身体形状既可以是物种进化和生态的结果，也可以是其原因。有许多与特定生态位相关的表型例子，可能是特定选择机制的结果。一个典型的例子是与洞穴殖民相关的表型变化，包括身体和肢体的伸长。然而，明确测试穴居和非穴居谱系之间体形差异的研究有限，因此洞穴环境在确定形态特征中的作用仍不完全清楚。在这里，我们研究了代表蝾螈属（Plethodontidae）20个物种的405个个体的体形变异，并选择了在形态、生态位和生活史方面表现出巨大多样性的外类群。结果在使用系统发育多元方差分析和系统形态空间检查在系统发育背景下分析形态测量数据后，我们发现洞穴居住物种和非洞穴居住物种之间以及不同物种之间的体形存在显着差异。水生和陆生物种。值得注意的是，穴居物种的特征是肢体伸长、身体和尾巴尺寸减小。陆生物种也表现出四肢和手指的伸长。我们还观察到幼态性和双相性物种之间形状变异的差异。我们的结果表明，栖息地和生活史所施加的功能限制在该群体的系统发育历史背景下的体形进化中发挥了关键作用。
BackgroundBody shape can be both a consequence and cause of a species' evolution and ecology. There are many examples of phenotypes associated with specific ecological niches, likely as a result of specific selective regimes. A classic example of this is the phenotypic change associated with colonization of caves, including body and limb elongation. However, studies explicitly testing for differences in body shape between cave-dwelling and non-cave-dwelling lineages have been limited and so the role of the cave environment in determining morphological characteristics is still not completely understood. Here we examine variation in body shape among 405 individuals representing 20 species in the salamander genus Eurycea (Plethodontidae) and select outgroups exhibiting great diversity in morphology, ecological niche, and life history.ResultsAfter analyzing morphometric data in a phylogenetic context using phylogenetic MANOVA and examination of the phylomorphospace, we found significant differences in body shape among cave-dwelling and non-cave-dwelling species and between aquatic and terrestrial species. Notably, limb elongation and reduced body and tail size characterized cave-dwelling species. Terrestrial species also exhibited elongation of the limbs and digits. We also observed differences in shape variance among paedomorphic and biphasic species. Our results suggest that the functional limitations imposed by habitat and life history played a key role in the evolution of body shape in this group in the context of their phylogenetic history.