Macaca mulatta

While the importance of the early years of life in affecting adult outcomes is now recognized, establishing the existence of a causal effect on health of early exposure to adversity can be a challenging task. In this paper, we exploit a unique ongoing experiment in a colony of rhesus monkeys to provide causal evidence of the health effects of early maternal and social deprivation. We show that the lack of a secure attachment relationship in the early years has detrimental consequences for both physical and mental health later in life, with long-lasting effects which vary by gender. The persistence of these effects after the end of the treatment emphasizes the need to intervene early in life to prevent long-term damage.

That is from the new paper "Primate Evidence on the Late Health Effects of Early Life Adversity" by Conti et al (April 2012). James Heckman is a coauthor.