Asked by: Sophie Clay, Manchester
Charles Darwin was intrigued by blushing, calling it “the most peculiar and most human of all expressions”, but it would be more than 125 years before we had any hard data on what evolutionary function blushing might have.
We now know that when people blush after a transgression or mishap, their state of shame and embarrassment is considered more intense by onlookers, and as a consequence they are viewed more favourably – perhaps because it signals their realisation and regret that they have transgressed. For instance, in one study, Dutch psychologists found that cheaters in a financial game who subsequently blushed were soon trusted again.
So blushing seems to have evolved as a form of non-verbal communication, helping us to bond with others by showing our concern for social rules.
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