But the study, conducted by scientists at Charles University in Prague, determined that the facial shape associated with brown-eyed people may be the reason for this perception, rather than eye colour itself.
“Brown-eyed people are more trusted than blue-eyed people. It’s not because of the eye colour, but because of the specific face shape that is associated with this eye colour,” said Dr. Karel Kleisner, lead author of the study that was published Wednesday in the journal PLOS One.
One surprising finding of the study was the “seminal association” between facial shape/features and eye colour, Kleisner said.
Brown-eyed people, whose faces were generally rounder in shape, were perceived to be more trustworthy by others, while people with blue eyes, whose faces tended to be shaped more angularly, were perceived to be less trustworthy.
In the study, 238 participants were provided with 80 photographs of people with either brown or blue eyes — half male, half female — and asked to rate trustworthiness. A separate group of participants were asked to rate the same photographs with the eye colours reversed (using Photoshop) to ensure the findings from the first group held up.
The study focused only on brown eyes, the eye colour of more than half the world’s population, and blue. Brown and blue are the two most predominant eye colours of people in Central Europe, Kleisner noted.
“The human face, in general, conveys a lot of important information about individuals, like age, health, sex, social status and so on. And the eyes are not just the organ of sight, they are also the semantic organ to which different meanings could be attributed and could be tied to different social stereotypes,” he added.