Data from: Contrasting patterns of gene flow for Amazonian snakes that actively forage and those that wait in ambush

Knowledge of genetic structure, geographic distance and environmental heterogeneity can be used to identify environmental features and natural history traits that influence dispersal and gene flow. Foraging mode is a trait that might predict dispersal capacity in snakes, because actively foragers typically have greater movement rates than ambush predators. Here we test the hypothesis that two actively foraging snakes have higher levels of gene flow than two ambush predators. We evaluated these four co-distributed species of snakes in the Brazilian Amazon. Snakes were sampled along an 880km transect from the central to the southwest of the Amazon basin, which covered a mosaic of vegetation types and seasonal differences in climate. We analyzed thousands of Single Nucleotide Polymorphisms (SNPs) to compare patterns of neutral gene flow based on isolation by geographic distance (IBD) and environmental resistance (IBR). We show that IBD and IBR were only evident in ambush predators, implying lower levels of dispersal than the active foragers. Therefore, gene flow was high enough in the active foragers analyzed here to prevent any build-up of spatial genotypic structure with respect to geographic distance and environmental heterogeneity.

对种群遗传结构、地理距离及环境异质性的认知，可用于识别影响扩散与基因流的环境特征及自然历史性状。觅食模式可作为蛇类扩散能力的预测性性状：主动觅食者的移动速率普遍高于伏击型捕食者。本研究验证如下假说：两种主动觅食蛇类的基因流水平高于两种伏击型捕食蛇类。我们在巴西亚马逊地区针对这4种同分布蛇类开展研究。研究沿亚马逊盆地中部至西南方向的880公里样带采集蛇类样本，该样带覆盖了多样的植被类型与气候季节差异。我们通过分析数千个单核苷酸多态性（Single Nucleotide Polymorphisms, SNPs），对比了基于地理距离隔离（Isolation by Geographic Distance, IBD）与环境抗性隔离（Isolation by Environmental Resistance, IBR）的中性基因流模式。结果显示，地理距离隔离与环境抗性隔离仅在伏击型捕食者中显著存在，这意味着它们的扩散水平低于主动觅食者。因此，本研究中分析的主动觅食者的基因流水平足够高，足以阻止其空间遗传结构随地理距离与环境异质性发生累积。