Data from: Male eyespan size is associated with meiotic drive in wild stalk-eyed flies (Teleopsis dalmanni)

This study provides the first direct evidence from wild populations of stalk-eyed flies to support the hypothesis that male eyespan is a signal of meiotic drive. Several stalk-eyed fly species are known to exhibit X-linked meiotic drive. A recent QTL analysis in Teleopsis dalmanni, found a potential link between variation in male eyespan, a sexually selected ornamental trait, and the presence of meiotic drive. This was based on laboratory populations subject to artificial selection for male eyespan. In this study we examined the association between microsatellite markers and levels of sex ratio bias (meiotic drive) in 12 wild T. dalmanni populations. We collected two data sets: a) brood sex ratios of wild-caught males mated to standard laboratory females, and b) variation in a range of phenotypic traits associated with reproductive success of wild- caught males and females. In each case, we typed individuals for 8 X-linked microsatellite markers, including several that previously were shown to be associated with male eyespan and meiotic drive. We found that one microsatellite marker was very strongly associated with meiotic drive whilst a second showed a weaker association. We also found that, using both independent datasets, meiotic drive was strongly associated with male eyespan, with smaller eyespan males being associated with more female-biased broods. These results suggest that mate preference for exaggerated male eyespan allows females to avoid mating with males carrying the meiotic drive gene and is thus a potential mechanism for the maintenance and evolution of female mate preference.本研究首次获得来自突眼蝇（stalk-eyed fly）野生种群的直接实验证据，用以验证“雄性眼柄长度可作为减数分裂驱动（meiotic drive）信号”这一假说。目前学界已在多种突眼蝇物种中发现X连锁减数分裂驱动现象。近期一项针对达氏突眼蝇（Teleopsis dalmanni）的数量性状基因座（quantitative trait locus, QTL）分析发现，雄性眼柄长度的变异——一种经性选择演化而来的装饰性性状——与减数分裂驱动的存在存在潜在关联，该结论基于针对雄性眼柄长度进行人工选育的实验室种群得出。本研究针对12个达氏突眼蝇野生种群，探究了微卫星标记（microsatellite marker）与性比偏倚（即减数分裂驱动）水平之间的关联。本研究采集了两类数据集：a）野外捕获雄性与标准实验室雌性交配后的子代性比数据；b）野外捕获雌雄个体一系列与繁殖成功率相关的表型性状变异数据。针对上述两类数据集，我们均对所有个体开展了8个X连锁微卫星标记的基因分型，其中部分标记此前已被证实与雄性眼柄长度及减数分裂驱动存在关联。研究结果显示，某一微卫星标记与减数分裂驱动存在极强的关联，而另一标记则仅呈现较弱的相关性。此外，基于两类独立数据集的分析均表明，减数分裂驱动与雄性眼柄长度存在显著关联：眼柄更短的雄性对应的子代性比更偏向雌性。上述结果表明，雌性对雄性更长眼柄的配偶偏好，可使其避免与携带减数分裂驱动基因的雄性交配，这一机制或为雌性配偶偏好的维持与演化提供了潜在解释。