Quite possibly, our strong desire for close friends evolved among our early ancestors because having a close friend improved one’s chances of survival and the survival of one’s children.
In part, we make friends because we don’t want to be alone, and that’s a proximate cause. We want a helpmate and a companion who makes us feel valued. We want someone to love us, despite our faults, and defend us when maligned. Close friends help us navigate the stormy seas of life and comfort us when we fail. Close friends make us feel better.
In a study of 323,000 people across 99 countries, friendship was linked to better health, greater happiness, and a higher level of well-being. If close, loving friendships are an adaptive trait that evolved among early humans, we should expect that close friendships are common and valued across cultures.
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[For example,] among the Akwe-Shavante, indigenous people of western Brazil, parents encourage their sons to develop one or two close friends, their i-amo (“my other” or “my partner”), who become their companion for life. Among the Bangwa of Cameroon… when a man dies, his best friend pays for the funeral.
While the expression of friendship differs across cultures, close loving friendships are quite common, suggesting an underlying evolutionary trait.