In the wake of the blue and black dress that gripped the internet last week, the topic of color perception has been weighing heavily on our collective minds. Kevin Loria of Business Insider Australia has gone one step further by tackling the history of human perception of the color blue. Loria's investigation includes the origins of the word blue, and suggests that perception did not exist before there was a word to describe it. The basis of Loria's feature was Colors, an episode of the Radiolab podcast. In it, they discuss the first known instances of the word blue.

About 150 years ago, a British scholar named William Gladstone was studying Homer’s "The Odyssey" and noticed that the poet had some unconventional descriptions of color. For instance, honey was described as green, while iron was called violet. However, no mention of blue existed. Similar investigations into ancient texts of a number of other languages were also missing any mention of the word blue. In fact, the first mention of blue wasn't found in any language until about 4,500 years ago. Was it possible that they weren’t able to perceive it as we do now?

Psychologist Jules Davidoff traveled to Namibia in order to conduct an experiment with the Himba tribe. Their language has no distinct word for blue, and when asked to choose a blue square among a group of green squares, they had extreme difficulty.

Image credit: Jules Davidoff via Business Insider

However, their language is much more descriptive when it comes to green. As apparent as the blue square looks to us in the picture above, the Himba people are able to detect which green square below is unlike the others. Can you spot the green square that is a different shade than the rest?

Image credit: Jules Davidoff via Business Insider

Below, the image tells you which one is the odd green square. Once you’ve seen the one that is supposed to be different, it becomes easier to go back and see the distinction above.

Image credit: Jules Davidoff via Business Insider

Because color only exists as it is perceived by an individual, it becomes hard to definitively say what our ancestors did or did not see. Were they really colorblind to it entirely? Or did they merely lack the vocabulary to articulate what it was they were seeing? Or did their brain not bother to view blue as distinct from other colors?

If you’d like to learn more about the color experiment with the Himba tribe, the origin of the word blue, and extreme instances of color perception in humans and in animals, check out the Radiolab podcast episode Colors right here: