What accounts for personality maturation in early adulthood?

During early adulthood, individuals tend to increase in personality traits that mark greater social maturity. The compelling question is why most young adults change in the direction of greater maturity. Recently, this question has been addressed by a diverse array of research, ranging from behavioral-genetic to prospective longitudinal and cross-cultural studies. The present article reviews the new insights gained from these studies, discusses their implications for two theoretical accounts of personality-trait development, and highlights challenges for future research.
Keywords: personality development, Big Five, social investment, culture, behavioral genetics, early adulthood