Leung Ka Wah, Yang Shengnan, Wang Xiaoyi, Tang Ke, Hu Junhua
Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Biology (Basel). 2021 Oct 22;10(11):1081. doi: 10.3390/biology10111081.
Several anurans have broad elevational and latitudinal distribution ranges; distinct species and populations may face various environmental and selection stresses. Due to their environmental sensitivity, adaptation is critical for the long-term persistence of anurans. Previous studies have tried to identify the ecogeographical pattern and its mechanism in anurans, suggesting different patterns, but the related explanatory mechanisms are yet to be generally supported and are suggested to be complicated. To explore the elusive mechanisms, we studied the morphological variation of the plateau brown frog () along an elevational gradient on the eastern margin of the Qinghai-Tibetan Plateau. Using body size, extremity length, and the ratio between them (extremities/body size) as testing indicators, we examined potential ecogeographical adaptations and investigated how environmental and biological factors could shape the morphological development in . We found that males and females showed different variations in body size and extremities along the elevational gradient, whereas both of them showed a decreasing extremities/body size ratio along elevation. Together with the strong correlations between environmental and biological factors and the morphometrics, we identified ecogeographical adaptation and a sexual difference in the selective pressures on the extremities and body size of the plateau brown frog. Our results imply that geographic variations in anuran morphological traits should be understood as an outcome of environmental and biological factors. Furthermore, ecogeographical adaptation in anurans can manifest as an interactive change between body size and extremities.
几种无尾目动物具有广泛的海拔和纬度分布范围；不同的物种和种群可能面临各种环境和选择压力。由于它们对环境敏感，适应对于无尾目动物的长期生存至关重要。先前的研究试图确定无尾目动物的生态地理模式及其机制，提出了不同的模式，但相关的解释机制尚未得到普遍支持，且被认为很复杂。为了探索这些难以捉摸的机制，我们研究了青藏高原东缘高原林蛙（ ）沿海拔梯度的形态变异。以体型、肢体长度以及它们之间的比例（肢体/体型）作为测试指标，我们检验了潜在的生态地理适应性，并研究了环境和生物因素如何塑造高原林蛙的形态发育。我们发现，雄性和雌性在沿海拔梯度的体型和肢体方面表现出不同的变化，而它们在海拔升高时肢体/体型比例均呈下降趋势。结合环境和生物因素与形态测量之间的强相关性，我们确定了高原林蛙在肢体和体型选择压力方面的生态地理适应性和性别差异。我们的结果表明，无尾目动物形态特征的地理变异应被理解为环境和生物因素的结果。此外，无尾目动物的生态地理适应性可以表现为体型和肢体之间的交互变化。
