A woman from an Amazonian hunter-gatherer group called the Tsimane’ describes colors in her native language to a cognitive scientist.

Edward Gibson

Is the sky really blue? Some hunter-gatherers don’t describe colors the same way most people do

Ask almost any child in the developed world what color the sky is, and you’ll get the same answer. But pose the question to a hunter-gatherer from the Amazon, and it may be a while before you hear the word for “blue,” if you ever do. That’s the conclusion of a new study, which finds that the ability to describe colors isn’t as rooted in our biology as many scientists thought. And that means that language development may be far more rooted in our culture than in how we literally see the world.

To conduct the study, Edward Gibson, a cognitive scientist at the Massachusetts Institute of Technology in Cambridge, hauled a car battery–powered light box and 80 standardized color chips down the Amazon River. He wanted to connect with the Tsimane’, a group of hunter-gatherers that live deep in the jungles of South America and developed their language in isolation from other nearby groups.

The Tsimane’ have fewer words for colors than American English speakers and Bolivian Spanish speakers, and they had a harder time agreeing on what to call each color, the team reports today in the Proceedings of the National Academy of Sciences.

But not all colors were equal. When it came to black, white, and red, the Tsimane’ were as good as their foreign counterparts in identifying the color. (A 2015 study of Hadza hunter-gatherers in Africa showed a similar result.) The words for “black” and “white” tend to derive from words for “light” and “dark,” which are universal concepts, and “red” is easily identified because it is the color of blood. This may be one universal principle of the way languages communicate color, says study leader Bevil Conway, a neuroscientist at the National Institutes of Health in Bethesda, Maryland.

What’s more, all three languages in the study were better at describing “warm” colors like yellows and oranges. But they were less precise in describing “cool” colors like blue and green. Even with their less-developed color vocabulary, the Tsimane’ were better at describing warm colors than cool colors. The study showed that the same principle is true in English and Spanish. This seems to be another feature of color terms that cuts across cultures.

To find out why, Gibson and Conway also examined a data set collected by Microsoft of 20,000 photographs. In those images, the cool-colored pixels were much more likely to record the photograph’s background (trees, sky, etc.), and warm-colored pixels were much more likely to represent a “behaviorally relevant” object such as food or clothing.

“The objects we want to talk about are warm colored,” Gibson says. Whether a person lives in a hunter-gatherer society or an industrialized one, the objects that need to be described tend to be warm colored, so languages develop more words for those colors. “We have a word for a color when we have two things that are identical except for color,” he continues, “Yes, the sky is blue, but there aren’t two skies.”

The differences between the Tsimane’ language and Spanish or English come from the fact that the Tsimane’ and other hunter-gatherers don’t need to describe as many colors in the course of their daily routines. The languages of industrialized cultures have more identical objects to describe: We need to be able to distinguish the blue coffee cup from the green one, or the red car from the yellow car. Therefore a more expansive color vocabulary than seen in hunter-gatherer cultures developed, according to Conway and Gibson.

Color descriptions between languages aren’t different because people see different things, Gibson explains. Color vocabularies are different across cultures because those cultures need different things from language. “We see the same colors as hunter-gatherers,” he says, “but they don’t need to label those colors.”

Another reason that people in industrialized cultures have a more developed language for color has to do with the ability to make choices, says Debi Roberson, a cognitive psychologist at the University of Essex in the United Kingdom who has studied color vocabulary among the indigenous people of Namibia and Papua New Guinea. “We live in a manufactured environment where we can choose what color our clothes, or anything else, are” she says. “If you live in a natural environment, you have absolutely no control over color whatsoever.”