In a new study, evolutionary psychologist Quentin Atkinson is using the popular tale of the kind and unkind girls to study how human culture differs within and between groups, and how easily the story moved from one group to another.

Atkinson, of the University of Auckland in New Zealand, and his co-authors employed tools normally used to study genetic variation within a species, such as people, to look at variations in this folktale throughout Europe.

The researchers found that there were significant differences in the folktale between ethnolinguistic groups—or groups bound together by language and ethnicity. From this, the scientists concluded that it's much harder for cultural information to move between groups than it is for genes.

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