The Caribbean archipelago offers one of the best natural arenas for testing biogeographic hypotheses. The intermediate dispersal model of biogeography (IDM) predicts variation in species richness among lineages on islands to relate to their dispersal potential. To test this model, one would need background knowledge of dispersal potential of lineages and their biogeographic patterns, which has been problematic as evidenced by our prior work on the Caribbean tetragnathid spiders. In order to investigate the biogeographic imprint of an excellent disperser, we study Trichonephila in the Americas. Trichonephila is a nephilid genus that contains globally distributed species known to overcome long, overwater distances. The results of our phylogenetic and population genetic analyses on T. clavipes suggest that populations over the Caribbean and North America maintain a lively gene flow. However, the single species status of T. clavipes over the entire New World is challenged by our species delimitation analyses. Combined with prior evidence from spider genera of different dispersal ability, these patterns coming from an excellent disperser (Trichonephila) that is species‐poor and of a relatively homogenous genetic structure, support the IDM predictions.

中文翻译：

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加勒比金色圆蛛蜘蛛与北美保持基因流动

加勒比群岛是测试生物地理假设的最佳自然场所之一。生物地理学 (IDM) 的中间扩散模型预测岛屿上谱系之间物种丰富度的变化与其扩散潜力相关。为了测试这个模型，人们需要了解谱系及其生物地理模式的传播潜力的背景知识，正如我们之前对加勒比四爪蜘蛛的工作所证明的那样，这是有问题的。为了研究一个优秀的分散器的生物地理印记，我们研究了美洲的Trichonephila。Trichonephila 是一种nephilid 属，包含全球分布的物种，已知可以克服长距离的水上距离。我们对 T 的系统发育和群体遗传分析的结果。clavipes 表明加勒比海和北美洲的人口保持着活跃的基因流。然而，我们的物种定界分析挑战了整个新大陆 T. clavipes 的单一物种地位。结合来自不同传播能力蜘蛛属的先前证据，这些模式来自物种贫乏且具有相对同质遗传结构的优秀传播者（Trichonephila），支持IDM预测。