The Maternal Capital Hypothesis: Giving Mothers Central Place in Evolutionary Perspectives on Developmental Plasticity and Health.

The "developmental origins of health and disease" paradigm has revolutionized biomedical research and raised new questions in the public domain. Not only individual disease risk, but also population health inequalities, may be profoundly shaped by experience early in life. The maternal capital hypothesis, published in 2010, is an evolutionary conceptual framework for understanding developmental plasticity on an intergenerational time-scale. The central proposition is that societal adversities can become embodied in maternal phenotype, and hence undermine the health and life opportunities of their offspring. The offspring calibrates its early developmental trajectory to maternal phenotype, not to the external environment. The framework emphasizes societal stresses from which individual mothers cannot opt out, such as malnutrition, poverty, gender inequality, colonialism, racism, war, and interpersonal violence. Conversely, mothers with greater capital can better defend themselves against these stresses and buffer their offspring. In this commentary, I revisit why the hypothesis was developed and summarize how it has stimulated further work. I review evidence for the role of maternal phenotype in the intergenerational basis of health inequalities; theoretical issues that the hypothesis can help clarify; implications for policy and intergenerational justice; and experimental studies that show that promoting maternal capital can have health benefits for both mothers and offspring. There is no intention to blame mothers when arguing that maternal phenotype plays a unique role in intergenerational cycles of disadvantage. Rather, promoting maternal capital may not only improve maternal and child health, but also combat gender and racial inequality.