Only 20% of Humans Have a Dimple in Their Chin — An Evolutionary Biologist Explains Why

An explainer says the human chin is a uniquely human trait, and chin dimples are a common inherited variation.

Chin dimples likely result from incomplete fusion of the jaw or development of the mentalis muscle.

The trait appears to involve multiple genes and has no known functional role.

The article highlights chin dimples as an example of appearance shaped by development, not clear evolutionary function.