Pili Gemini

Pili gemini defines a situation where the papilla's tip of a hair follicle splits during the anagen phase and consequently grows two hair shafts emerging through a single pilary canal. A papilla tip that divides in several tips will produce several hair shafts, a situation named pili multigemini. Pili gemini or multigemini can occur in each type of hair.

Epidemiology

The prevalence of this anomaly is unknown but might be very high, so much so that it could be supposed to be an evolutional trait.