What evidence is there of that?
Definitely no archeological evidence that I know of.
Perhaps a better version of the idea in natural human behavior would be prejudice against “those who are not us”.
As in those who are not of our clan, of our tribe, are not of our culture, are not of our religion.
This would be the natural distrust of people you do not know which is, I believe a genetically passed on survival trait.
A stranger shows up in your hunting grounds. Is he there to take a few of your deer or is he there to take your women and kill your children?
A stranger shows up in your hunting grounds. Is he there to take a few of your deer or is he there to take your women and kill your children?
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This observation is no doubt what motivated Rudyard Kipling to compose the poem ‘The Stranger’.