Foundations of Behavior Genetics

To understand heredity–behavior relations it is important to first understand the mechanisms of heredity. The gains in knowledge about genetics in the twentieth century are stunning. An obscure scientific paper that was published in the late nineteenth century and rediscovered at the beginning of the twentieth laid the foundation for identifying the molecule of heredity about fifty years later, and for the project to map all human genes about fifty years after that. Basic principles of genetics are taught in middle schools today and it is generally accepted that genetic variation plays a role in individual differences in behavior. In this chapter we discuss some ideas about heredity that predate our modern understanding. We also examine the life of two important figures in the history of genetics and describe their contributions.