An old popular Galician song said:
Ollos verdes son traidores…
azules son mentireiros,
os negros e acastañados son firmes e verdadeiros.
Green eyes are treacherous…
blue ones are deceitful,
the black and brown ones are loyal and truthful.
Just word of a silly mariner song? Intriguingly science confirms now, in a way, part of this perception (at least for blue and brown eyes).
But notice please that it is the precisely the perception what is being confirmed: people seem to perceive blue eyes in general as somewhat less trustworthy. The study says nothing about people with blue eyes being untrustworthy in fact, just that we tend to distrust them more than people with brown eyes.
Karel Kleisner et al., Trustworthy-Looking Face Meets Brown Eyes. PLoS ONE 2013. Open access → LINK [doi:10.1371/journal.pone.0053285]
We tested whether eye color influences perception of trustworthiness.
Facial photographs of 40 female and 40 male students were rated for
perceived trustworthiness. Eye color had a significant effect, the
brown-eyed faces being perceived as more trustworthy than the blue-eyed
ones. Geometric morphometrics, however, revealed significant
correlations between eye color and face shape. Thus, face shape likewise
had a significant effect on perceived trustworthiness but only for male
faces, the effect for female faces not being significant. To determine
whether perception of trustworthiness was being influenced primarily by
eye color or by face shape, we recolored the eyes on the same male
facial photos and repeated the test procedure. Eye color now had no
effect on perceived trustworthiness. We concluded that although the
brown-eyed faces were perceived as more trustworthy than the blue-eyed
ones, it was not brown eye color per se that caused the stronger perception of trustworthiness but rather the facial features associated with brown eyes.
So the authors conclude that it is not eye color but associated face shape what drives untrustworthiness because the phenotype associated with blue eyes is more angular, less rounded, at least for males:
|Figure 2. Shape changes associated with eye color and perceived trustworthiness.
spline visualizations of the way face shape correlates with eye color
(a–f) and trustworthiness (g–i). Generated face shapes of blue-eyed
woman (a) and brown-eyed woman (c) compared to average female face (b).
Generated face shapes of blue-eyed man (d) and brown-eyed man (f)
compared to average male face (e). Generated face shapes of
untrustworthy-looking man (g) and trustworthy-looking (i) man compared
to average male face (h). The TPS grids of perceived trustworthiness for
women are not shown because shape analysis did not meet statistical
significance. The generated facial images (a–f) were magnified 3x for
They claim that they found no correlation with facial shape for women but I find in the image above almost exactly the same pattern for men and women and not only what they detected: notably the blue eyed people (both genders) and the less trusted men all have in my opinion:
- Smaller eyes
- More serious (defiant, analytic, unsympathetic) expression
- Proportionally broader face or at least jaws
In general the faces to the left look significantly colder, less empathic, a perception that blue eyes can only enhance.
The authors ponder if there is a phenotype linkage disequilibrium associating face and eye color, what seems plausible. But then go on speculating about sexual selection and what not.
In this sense Razib has an interesting critical analysis
questioning if selection is behind the blue eye incomplete sweep in West Eurasia or Europe. If I understand him correctly he seems to suggest, never clearly naming it, that blue eye may have been favored because of the associated skin pigmentation trait, a key adaptive value in the dark winters of Europe and very especially the northern half of it.
Update: is this a peculiarity of Central Europe or the Czech Republic?
A reader sent me an email in which it was questioned if this association is peculiar of the Czech Republic, where the study was performed, and can’t be extended for example to Britain. Examples of soft-faced blue-eyed Britons mentioned were Hugh Grant and Alec Baldwin (I’m not sure if Baldwin is such a good counter-example but Grant is for sure one such case).
I find it a very good criticism and hope that entices debate.
See also: Causes of skin and hair color variance in Europeans remain undetermined.