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Fig. S2. RNL chromaticity for each ROI as modeled for each of the nine color vision phenotypes. Capuchin color vision phenotypes are denoted by the nanometers at which each of their cone types are most sensitive (e.g., 426-536 for a monkey with two receptor types with peak sensitivities at those values). Error bars represent +/-1 SD, and dashed lines estimate the region of color space with no chromatic signal.

Fig. S2. RNL chromaticity for each ROI as modeled for each of the nine color vision phenotypes. Capuchin color vision phenotypes are denoted by the nanometers at which each of their cone types are most sensitive (e.g., 426-536 for a monkey with two receptor types with peak sensitivities at those values). Error bars represent +/-1 SD, and dashed lines estimate the region of color space with no chromatic signal.

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... However, more recent research points to a broad variety of social and ecological factors that in uence the diversity in external eye appearance in primates; for example, such diversity may be driven by the behavioral ecology of speci c lineages, such as the spectral quality and quantity of light from the sun in the species' range (Perea-García et al., 2022) 7 . Furthermore, functional studies 8 as well as simulations 9,10 show that the eye-gaze of other primate species previously considered to have cryptic eye gaze is actually conspicuous, supporting the proposal by Perea-García et al (2019) 11 based on comparative morphological evidence. This is especially interesting in the case of the chimpanzee, which are characterized by deeply pigmented conjunctiva, but whose typically bright amber irises create a stark contrast between these two tissues. ...
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