That’ll be the newspaper taglines, at least.
Behavioural inhibition in young children appears to be more frequent in blue-irised American children, and now in blond(er) German children. The putative link is made between melanocyte-stimulating hormones and cortisol (stress-related) stimulators as the underlying mechanism.
Interesting stuff, and will no doubt be picked up on for its quirk value, but it is the kind of research that is a little “so what?” in terms of what one does with that information. Cuddle fair-headed kids more? I bet they already get a little more attention 😉
I do get a bit antsy at the use of cross-cultural to describe findings such as these. I suppose it depends on where your draw your cultural boundaries (and for what purposes), but the danger is that “cross-cultural” is so very easily conflated with “human universal”. If we’re speaking of worldwide cultural variation, Caucasian Americans and Germans are pretty close to sister-taxa.