Levels of "FOXP2" in adult zebra finches are significantly higher when males direct their song to females than when they sing song in other contexts. “Directed” singing refers to when a male is singing to a female usually for a courtship display. “Undirected” singing occurs when for example, a male sings when other males are present or is alone. Studies have found that FoxP2 levels vary depending on the social context. When the birds were singing undirected song, there was a decrease of FoxP2 expression in Area X. This downregulation was not observed and FoxP2 levels remained stable in birds singing directed song.