Westermarck effect

The Westermarck effect states that children who grew up together or who spent a large part of their childhood together would not find each other sexually attractive.

The effect is named after Edvard Westermarck, a Finnish sociologist. According to Westermark, the idea is to prevent incest or inbreeding. Choosing another partner gives an advantage, so this is not a cultural phenomenon.

References

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