The five theories are the static or population heterogeneity models; dynamic or state dependence models; social psychological theories; the developmental psychopathology perspective; and the biopsychosocial perspective. Static or population heterogeneity models view human development "as a process of maturational unfolding" in which behavior, including criminal behavior, emerges in a uniform sequence contingent upon age, so that patterns of behavioral change unfold at approximately the same ages for all individuals. Dynamic or life-course developmental models adopt a sociogenetic approach. Human behavior is not viewed as set or established nor an inevitable path that stems from early endowments. Sociogenesis emphasizes "the uniquely 'open' or 'unfinished' character of the human organism in relation to its environment" (Dannefer, 1984). Social psychological theories focus on subjective aspects of life experiences as the key to understanding behavioral continuity and change. These experiences include cognitive and emotional processes, issues of identity, and human agency, i.e., the capacity for individuals to make choices. The developmental psychopathology perspective features an integrative framework that brings together ideas from the sciences of human development, general systems theory, clinical psychology, psychiatry, sociology, pediatrics, neuroscience, behavior genetics, and other disciplines concerned with good and poor adaptation over the life course. Under this perspective, early experiences influence subsequent behavior, but the possibility of change continues throughout the lifespan. The biopsychosocial model regards aggressive behavior as a result of interacting mechanisms at biological, psychological, interpersonal, and environmental levels. 100 references