ABSTRACT
When discussing individual differences in behavior or physiology, it is common to suggest that they reflect a contribution of “nature and nurture,” typically interpreted to mean that environmental influences beginning after birth build on the innate substrate provided by genetic factors (Rutter et al., 1990). The findings discussed in this chapter offer another perspective, because they suggest that there is an additional way through which the behavior and physiology of the individual can emerge and be shaped. Our studies focused on the prenatal in utero environment and its potential influence on fetal and infant development. This research demonstrated that events impinging on the pregnant female can have an enduring effect on her offspring, changing the expression of behavior at birth and even later in infancy. The experiments were carried out in monkeys, which permitted a more rigorous control over the pregnancy conditions and early rearing environment than would be possible in children.
