Abstract
Languages vary in their number of color terms. Why? The two dominant theories (universalist hypothesis and linguistic-relativity hypothesis), do not account for empirical evidence. Here we test an alternative, the "efficient-communication hypothesis", which postulates that all people with trichromatic vision have similar color perception, but vary in color language depending on the usefulness of color to behavior. We test this hypothesis in three groups: the Tsimane', a hunter-gatherer isolate in the Bolivian Amazon; Spanish speakers from San Borja, Bolivia; and English-speaking students in Boston. Compared to Spanish and English speakers, the Tsimane' interact less with industrialized objects, which are often only distinguishable using color. We hypothesized that color is less useful for the Tsimane'. We make three observations. First, when asked to label colored chips or objects, each population used about the same number of terms. But each Tsimane' individual was idiosyncratic in the color terms they used, unlike English and Spanish speakers, who were largely consistent. Second, the Tsimane' were less likely than English speakers to use color terms spontaneously in a contrastive object-labeling task. When confronted with objects distinguished only by color, English speakers spontaneously attached color labels to identify the objects but the Tsimane' did not. Third, the Tsimane' took longer than English speakers to label chip colors; in control experiments the Tsimane' were comparable to English speakers at labeling objects, showing that the Tsimane' understood the experimental task. The number of color terms used by Tsimane' individuals and the efficiency of color-term usage increased with increased exposure to Spanish, suggesting a mechanism for cultural transmission. Together, these results suggest that the variability in the number of color terms across cultures is not caused by language itself, nor an innate set of universal color categories, but rather variability in the relative cost-benefit associated with expanding color vocabulary.
Meeting abstract presented at VSS 2016