Evolution of genetic variation for condition-dependent traits in stalk-eyed flies
Evolution of genetic variation for condition-dependent traits in stalk-eyed flies
复制标题
茎眼果蝇条件依赖性状遗传变异的进化
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
M. Taper
中科院分区：
文献类型：
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作者：
G. Wilkinson;M. Taper
已经提出性选择可以增加条件依赖性装饰品的遗传变异。条件捕获模型根据条件的遗传方差以及装饰品和条件之间的关系的斜率来预测性选择性状的遗传方差。假设体型反映了身体状况，我们使用六种茎眼蝇（Diopsidae）评估该模型的功效。先前的证据表明，雄性眼跨表现出强烈的条件依赖性，并且在性二态性而非单态性物种中受到性选择。相反，胸部宽度与条件的相关性较弱，可能处于稳定选择之下。我们根据半同胞育种研究估计了眼跨、体长和胸宽的加性遗传方差，发现条件捕获模型解释了 97% 的眼跨遗传方差，但只能解释 7% 的胸宽遗传方差。系统发育独立对比的比较表明，男性眼跨度遗传方差的进化变化是由于眼跨度和条件之间的异速关系的进化变化造成的：而不是条件遗传方差的进化变化。这些结果表明，性选择可以通过增加可供选择的遗传变异来加速条件依赖性雄性饰物的进化变化。
Sexual selection has been proposed to increase genetic variation for condition-dependent ornaments. The condition capture model predicts the genetic variance for a sexually selected trait from the genetic variance in condition and the slope of the relationship between the ornament and condition. Assuming that body size reflects condition we assess the efficacy of this model using six species of stalk–eyed flies (Diopsidae). Prior evidence indicates that male eye span exhibits strong condition dependence and is under sexual selection in sexually dimorphic but not monomorphic species. In contrast, thorax width is weakly related to condition and probably under stabilizing selection. We estimated additive genetic variances for eye span, body length and thorax width from half–sib breeding studies and found that the condition capture model explained 97% of the variation in eye span genetic variance but only 7% of thorax width genetic variance. Comparison of phylogenetically independent contrasts revealed that evolutionary change in male eye span genetic variance is due to evolutionary change in the allometric relationship between eye span and condition: not to evolutionary change in genetic variance for condition. These results suggest that sexual selection can accelerate evolutionary change in condition-dependent male ornaments by increasing the genetic variation available for selection.