MAY 29, 2019
by Robin A. Smith, Duke University
Birds may not have a word for maroon. Or burnt sienna. But show a zebra finch a sunset-colored object, and she'll quickly decide whether it looks more like "red" or "orange."
A Duke University study shows that birdsmentally sort the range of hues on the blue-green side of the spectrum into two categories too, but the line between them is fuzzier.
It may be that "either/or" thinking is less useful in this part of the color spectrum, the researchers say. Deciding whether, say, a reddish-beaked male is good mate material, or which fruits are ripe is vital for survival, whereas the differences between shades of green grass or blue sky may be less so.
The findings come from a study of something called categorical perception, a mental hack in which the brain subdivides the smooth and continuous range of wavelengths in the visible spectrum into distinct groups of basic colors , such as red, orange, yellow, green, blue and purple.