Fig. 4.

Inferred distributions of communicative needs correlate with the colors of salient objects. (A) Human participants in the MSRA salient object study were asked to identify the foreground object in $\mathrm{20,000}$ images; example foreground mask is illustrated in gray. (B) WCS color chips ordered by their rank frequency in the foreground of MSRA images [rows “MSRA”; see Gibson et al. (23)], and in the inferred distribution of communicative need (rows “inferred”), averaged across the $n=130$ languages in the B&K+WCS survey data. There is a weak positive correlation between the colors that are considered salient, in the MSRA dataset, and the colors with greatest inferred communicative need, across all WCS color chips (Top). This relationship is strengthened after removing achromatic chips (WCS column 0, rows B and I) from the comparison (Bottom). (C) Colors of unripe (Top) and midripe and ripe (Bottom) fruit in the diets of catarrhine primates, derived from fruit spectral reflectance measurements collected in the Kibale Rainforest, Uganda, by Sumner and Mollon (38, 39). The colors of ripe fruit tend to correspond with the colors of greatest inferred communicative need. (D) Average log-probability in the inferred distribution of communicative need of color corresponding to unripe, midripe, and ripe fruit; $n$ denotes the number of fruit species, and $\mathrm{m}$ denotes the total number of spectral measurements. Error bars show $95\%$ CIs of the means (nonparametric bootstrap by species).