We present a novel analysis of fluctuating asymmetry (FA) for butterfly wings at the community-level, along an altitudinal gradient. FA is an important biomonitoring tool that detects deviations of perfect symmetry in bilateral characters, assuming that genetic and/or environmental factors can be a source of stress. This study evaluated the effects of increased altitude on the symmetry of butterfly wings, testing the hypothesis that FA should increase with increased elevation in a tropical mountain. Butterflies were sampled along an altitudinal gradient of 800 to 1.400 m and forewings were detached, scanned and evaluated for symmetry. Length, width and area of the right and left forewings were measured as surrogates for FA and then combined into an index taking into account the variability of wing sizes of the whole butterfly community. We observed true patterns of FA in the length, width and area of the wings, and wing FA area increased with increased altitude. This study pioneered the analysis of FA for a community of butterflies and FA was efficient to detect developmental instability indicated by imperfections in butterfly wings.

中文翻译：

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蝴蝶群落的翅膀不对称：海拔是压力的来源吗？

我们提出了一个新的分析，在社区层面上，沿着高度梯度，蝴蝶翅膀的波动不对称（FA）。FA是重要的生物监测工具，假设遗传和/或环境因素可能是压力的来源，它可以检测到双边性状完全对称的偏差。这项研究评估了海拔升高对蝴蝶翅膀对称性的影响，验证了热带山区FA随海拔升高而增加的假设。沿800至1.400 m的高度梯度采样蝴蝶，并分离前爪，扫描并评估对称性。测量左右前翅的长度，宽度和面积，作为FA的代用品，然后考虑到整个蝴蝶群落的机翼大小的可变性，综合成一个指数。我们在机翼的长度，宽度和面积上观察到FA的真实模式，并且机翼FA面积随高度的增加而增加。这项研究开创了对蝴蝶群落进行FA分析的先河，FA能够有效地检测出蝴蝶翅膀缺陷所指示的发育不稳定性。