Data from: Experimental evidence that primate trichromacy is well suited for detecting primate social colour signals

Primate trichromatic colour vision has been hypothesized to be well tuned for detecting variation in facial coloration, which could be due to selection on either signal wavelengths or the sensitivities of the photoreceptors themselves. We provide one of the first empirical tests of this idea by asking whether, when compared with other visual systems, the information obtained through primate trichromatic vision confers an improved ability to detect the changes in facial colour that female macaque monkeys exhibit when they are proceptive. We presented pairs of digital images of faces of the same monkey to human observers and asked them to select the proceptive face. We tested images that simulated what would be seen by common catarrhine trichromatic vision, two additional trichromatic conditions and three dichromatic conditions. Performance under conditions of common catarrhine trichromacy, and trichromacy with narrowly separated LM cone pigments (common in female platyrrhines), was better than for evenly spaced trichromacy or for any of the dichromatic conditions. These results suggest that primate trichromatic colour vision confers excellent ability to detect meaningful variation in primate face colour. This is consistent with the hypothesis that social information detection has acted on either primate signal spectral reflectance or photoreceptor spectral tuning, or both.灵长类三色视觉（Primate trichromatic colour vision）曾被假说认为可高度适配面部色彩变化的探测，该适配性或源于对信号波长或光感受器自身敏感度的选择压力。我们开展了该假说的首批实证检验之一，通过对比其他视觉系统，探究灵长类三色视觉所获取的信息，是否能提升检测雌性猕猴动情接受期面部色彩变化的能力。我们向人类观察者展示同一猕猴的成对数字面部图像，并要求其选出处于动情接受期的图像。我们测试了分别模拟普通狭鼻猴类（catarrhine）三色视觉、另外两种三色视觉条件以及三种二色视觉条件下的成像效果。在普通狭鼻猴类三色视觉，以及具备窄分离LM视锥色素（LM cone pigments，阔鼻猴类（platyrrhines）雌性常见）的三色视觉条件下，观察者的表现均优于等间距排布的三色视觉条件，或任意一种二色视觉条件。上述结果表明，灵长类三色视觉具备出色的探测灵长类面部色彩具有生物学意义变化的能力。这与‘社会信息探测曾作用于灵长类信号光谱反射率或光感受器光谱调谐，或同时作用于两者’的假说相一致。