Although there are many biological influences on adolescent psychology, adolescence does not take place in a cultural vacuum. The very concept of adolescence is a relatively recent one. Earlier in our history, there was less recognition of a transitional period between childhood and adulthood. Marriage, childbearing, and occupational maturity took place during the teen years. Although there was recognition of the special characteristics of “youth” (a period extending roughly from adolescence into early adulthood), most people took on an adult role within their society in their teens. As our society has become more complex, more and more time is needed to prepare for adult participation in society. Consequently, adolescence has come to be seen as unique period to be distinguished from both childhood and adulthood.