Not every trait necessarily confers a specific evolutionary advantage. Some traits may exist as side effects of other traits that do confer an advantage, or they simply may not confer enough of a disadvantage to have been bred out of the population.
Severe acne can run in families, but in general, zits are the result of pores being blocked so that the oils released by sebaceous glands build up. I doubt there is a specific gene or set of genes that causes all pimple formation. One’s susceptibility is probably increased by genes that influence one of the factors in the formation of zits, if the heritability is genetic in origin. In general, though, they seem to be just a relatively minor (although irritating) malfunction of the dermal system.
Not every trait necessarily confers a specific evolutionary advantage. Some traits may exist as side effects of other traits that do confer an advantage, or they simply may not confer enough of a disadvantage to have been bred out of the population.
Severe acne can run in families, but in general, zits are the result of pores being blocked so that the oils released by sebaceous glands build up. I doubt there is a specific gene or set of genes that causes all pimple formation. One’s susceptibility is probably increased by genes that influence one of the factors in the formation of zits, if the heritability is genetic in origin. In general, though, they seem to be just a relatively minor (although irritating) malfunction of the dermal system.