The processes that generate biodiversity occur at finer scales than are often studied, particularly in freshwater systems of the northern Neotropics. We investigate whether fine‐scale biogeographic patterns are present within the larger Grijalva–Usumacinta Area of Endemism (AoE) —a region in Middle America where nearly 60% of freshwater fishes are endemic—and if present‐day river basins are single historical units.

中文翻译：

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规模问题：破坏中美洲淡水鱼的地方性地区

与通常所研究的相比，产生生物多样性的过程规模较小，特别是在新热带北部的淡水系统中。我们调查了更大的格里耶尔瓦-乌苏马辛塔地方病（AoE）地区（中美洲一个近60％的淡水鱼类为地方病地区）以及目前的流域是否为单一历史单位的更大尺度的生物地理格局。