This theoretical essay focuses on some of the apparently evolved features of human adolescence and their possible functions. These include the pubertal growth spurt, sexual size dimorphism and bimaturism, the greater aggressiveness of males, heightened concern with one’s social standing and the factors affecting it, intergenerational friction, same-sex aggregations and solidarity, conformity, and interest in infants especially by girls. Evidence for an evolved basis for these traits is derived from cross-cultural, comparative, hormonal, and developmental research. The point is made that these types of research have a potential for revealing the universal features, and hence the essential nature, of adolescence.