Data from: Predation-associated differences in sex-linkage of wild guppy coloration

Evolutionary theory predicts that the sex-linkage of sexually selected traits can influence the direction and rate of evolutionary change, and also itself be subject to selection. Theory abounds on how sex-specific selection, mate choice, or other phenomena should favor different types of sex-linked inheritance, yet evidence in nature remains limited. Here we use hormone assays in Trinidadian guppies to explore the extent to which linkage of male coloration differs among populations adapted to varying predation regimes. Results show there is consistently higher degree of X- and autosomal linkage in body coloration among populations adapted to low-predation environments. More strikingly, analyses of an introduced population of guppies from a high to a low predation environment suggest that this difference can change in 50 years or less.

进化理论预测，性选择性状的性连锁（sex-linkage）可影响进化改变的方向与速率，且其本身亦会受到选择作用的影响。现有理论已就性特异性选择、配偶选择或其他现象如何偏向不同类型的性连锁遗传展开了大量研究，但自然界中的相关实证证据仍较为匮乏。本研究以特立尼达孔雀鱼（Trinidadian guppies）为研究对象，通过激素测定实验，探究雄性体色的连锁模式在适应不同捕食压力的种群间存在的差异程度。研究结果表明，适应低捕食压力环境的种群，其体色的X染色体连锁与常染色体连锁程度始终处于更高水平。更为引人注目的是，对从高捕食压力环境引入至低捕食压力环境的孔雀鱼引入种群的分析显示，这种连锁模式的差异可在50年乃至更短的时间内发生改变。