It is not so much genes or childhood environment that directly determine how successfully a person will cope, acquire knowledge and skills, and develop rewarding relationships as an adult.
Rather, it is the number of enduring relationships and activities a child has in his or her immediate environment that drives effective human development. So argue Urie Bronfenbrenner, the Jacob Gould Schurman Professor Emeritus of Human Development and Family Studies and of psychology, and Stephen Ceci, the Helen L. Carr Professor of Developmental Psychology.
Bronfenbrenner and Ceci propose that these relationships, called "proximal processes," are the mechanisms by which genetic potential gets actualized into behavior. Such proximal processes include parent-child and child-child activities, group or solitary play, reading, learning new skills, problem solving, and performing complex tasks.
The two researchers claim that the traditional nature versus nurture model of human development is seriously incomplete. Their empirically testable bioecological model goes beyond the current models and explains why genetics, socioeconomic class, race, and family wealth or demographics are not the primary forces that directly determine effective psychological functioning.
To show that some environments foster the natural talents of children while others do not, Bronfenbrenner and Ceci employ the commonly used formula to estimate heritability - an estimated measure of what proportion of the variation in a trait within a group is due to genetics.
"Genetic potentials for competence and character can only become actualized in a stable and supportive environment," says Bronfenbrenner. "But the world we are creating for ourselves and our children is increasingly chaotic, uncaring, and violent. …