Data from: Beauty in the eyes of the beholders: color vision is tuned to mate preference in the Trinidadian guppy (Poecilia reticulata)

A broad range of animals use visual signals to assess potential mates, and the theory of sensory exploitation suggests variation in visual systems drives mate preference variation due to sensory bias. Trinidadian guppies (Poecilia reticulata), a classic system for studies of the evolution of female mate choice, provide a unique opportunity to test this theory by looking for co-variation in visual tuning, light environment, and mate preferences. Female preference co-evolves with male coloration, such that guppy females from ‘low predation’ environments have stronger preferences for males with more orange/red coloration than do females from ‘high predation’ environments. Here we show that color vision also varies across populations, with ‘low’ predation guppies investing more of their color vision to detect red/orange coloration. In independently colonized watersheds, guppies expressed higher levels of both LWS-1 and LWS-3 (the most abundant LWS opsins) in ‘low predation’ populations than ‘high predation’ populations at a time that corresponds to differences in cone cell abundance. We also observed that the frequency of a coding polymorphism differed between high and low predation populations. Together this shows that the variation underlying preference could be explained by simple changes in expression and coding of opsins, providing important candidate genes to investigate the genetic basis of variation in this model system.诸多动物均借助视觉信号评估潜在配偶，而感官利用（sensory exploitation）理论提出，视觉系统的变异可通过感官偏向引发配偶偏好的差异。特立尼达花鳉（Poecilia reticulata）是研究雌性配偶选择演化的经典模式系统，为检验该理论提供了绝佳契机——可通过探究视觉调谐、光照环境与配偶偏好之间的共变异关系实现。雌性配偶偏好与雄性体色存在协同演化关系：相较于来自高捕食压力环境的花鳉雌性，低捕食压力环境中的雌性对橙红色体色更为艳丽的雄性表现出更强的偏好。 本研究表明，不同种群的色觉亦存在差异，低捕食压力种群的花鳉会投入更多视觉资源以感知红/橙色调。在独立定殖的流域中，低捕食压力种群的花鳉LWS-1与LWS-3（最为丰富的长波敏感视蛋白（LWS opsins））的表达水平均高于高捕食压力种群，且该差异与视锥细胞丰度的差异相吻合。我们同时发现，高、低捕食压力种群间的编码多态性频率存在差异。 综上，配偶偏好背后的变异可通过视蛋白表达与编码的简单改变得到解释，这为探究该模式系统中变异的遗传基础提供了重要的候选基因。