Genetic divergence in tropical anurans: deeper phylogeographic structure in forest specialists and in topographically complex regions
Genetic divergence in tropical anurans: deeper phylogeographic structure in forest specialists and in topographically complex regions
复制标题
DOI：
10.1007/s10682-015-9774-7
复制
发表时间：
2015-06
影响因子：
1.9
通讯作者：
Ariel Rodríguez;M. Börner;M. Pabijan;Marcelo Gehara;C. Haddad;M. Vences
中科院分区：
文献类型：
--
作者：
Ariel Rodríguez;M. Börner;M. Pabijan;Marcelo Gehara;C. Haddad;M. Vences
许多热带生物在种群之间表现出巨大的遗传差异，然而，潜在分化过程的普遍驱动因素尚不完全清楚。基于来自巴西、中美洲、古巴和马达加斯加的39种广泛分布的蛙类的2680个线粒体细胞染色质基因序列，研究了生境和自然历史特征（体型、大生境、小生境、繁殖地点、气候异质性和地形）对热带两栖动物种群遗传分化的影响。在信息论框架中实施广义线性模型来评估6个预测因子对种群间遗传差异的影响，以空间校正的两两距离来衡量。结果表明，地形复杂性和大生境偏好对种群分化有强烈影响，物种专为森林生境和/或来自地形复杂地区，具有更高的系统地理结构。在考虑类群之间的系统发育相关性后，这种关系发生了变化，使大生境偏好成为形成遗传分化的最重要特征。其余的预测因子对观察到的遗传分化的影响可以忽略不计。使用群体比例突变率（Θ）作为响应变量进行的类似分析显示，预测因子的影响很小。我们的研究结果表明，来自森林地区的无脊椎动物种群与来自开放栖息地的物种相比，具有更大的进化独立性。这种模式可能是由于热带雨林物种的繁殖要求较低的灵活性和严格性。相反，开放的景观可能提供短暂和不稳定的繁殖场所，适合于漂泊的多面手物种，导致减少种内分化。我们的研究结果预测，在给定的一段时间内，生活在森林中的热带无尾猿物种形成的机会应该高于适应开放栖息地的物种。
Many tropical organisms show large genetic differences among populations, yet the prevalent drivers of the underlying divergence processes are incompletely understood. We explored the effect of several habitat and natural history features (body size, macrohabitat, microhabitat, reproduction site, climatic heterogeneity, and topography) on population genetic divergence in tropical amphibians, based on a data set of 2680 DNA sequences of the mitochondrial cytochromebgene in 39 widely distributed frog species from Brazil, Central America, Cuba, and Madagascar. Generalized linear models were implemented in an information-theoretic framework to evaluate the effects of the six predictors on genetic divergence among populations, measured as spatially corrected pairwise distances. Results indicate that topographic complexity and macrohabitat preferences have a strong effect on population divergence with species specialized to forest habitat and/or from topographically complex regions showing higher phylogeographic structure. This relationship changed after accounting for phylogenetic relatedness among taxa rendering macrohabitat preferences as the most important feature shaping genetic divergence. The remaining predictors showed negligible effects on the observed genetic divergence. A similar analysis performed using the population-scaled mutation rate (Θ) as response variable showed little effect of the predictors. Our results demonstrate greater evolutionary independence among populations of anurans from forested regions versus species from open habitats. This pattern may result from lower vagility and stringency in reproductive requirements of rainforest species. Conversely, open landscapes may offer ephemeral and unstable breeding sites suitable for vagile generalist species, resulting in reduced intraspecific divergence. Our results predict that, for a given period of time, there should be a higher chance of speciation in tropical anurans living in forests than in species adapted to open habitats.