Molly Fox, an associate professor in the department of anthropology at UCLA, has pioneered research into the biological relationships between grandmothers, mothers and children.
During her doctoral training, Fox became fascinated by why women live so long after menopause and the evolutionary theory that grandmothers enhance the survival and reproductive success of their descendants. From this foundation, she built a research program that focuses on the adaptations that support cooperative care in human families. She investigates multigenerational caregiving and the evolutionary dynamics of women’s health issues.
Most recently, Fox led a study exploring how pregnancy and breastfeeding are associated with cognitive function in postmenopausal women. She and her team at the UCLA Biological Anthropology of Motherhood Lab found that greater cumulative time spent pregnant and breastfeeding was associated with less decline in cognition, verbal memory and visual memory later in life. This was surprising, as pregnancy and lactation are often interpreted as costly for women’s bodies. Understanding the biological processes behind these observations may help scientists develop preventive strategies for cognitive aging or neurodegenerative conditions.
This isn’t the first time Fox has made important discoveries about female evolutionary adaptations. The Yale alum and Gates Cambridge Scholar was also the lead author of a study on the biological underpinnings of morning sickness. Fox and her colleagues analyzed blood samples and questionnaire data from 58 Latina women in Southern California, following them from early pregnancy through the postpartum period. They found evidence that morning sickness symptoms may be part of an important immunological process that balances the protection of the fetus and mother. This may help combat stigma around morning sickness and encourage workplace accommodations for pregnant women.
Fox and her colleagues found that infants’ contact with caregivers, including the number of caregivers and more time in physical contact with multiple caregivers, was associated with greater diversity in the gut microbiome during the first 6 months of life, highlighting an underappreciated avenue by which cooperative childcare may manifest in human biological development and health. In related work, Fox and her team also observed that pregnant women exhibited better mental health when they had more contact and better relationships with their own mothers and siblings. Her work raises the possibility that modern disruptions of the interdependent family structures with which humans evolved may contribute to health problems, including perinatal mood disorders.
In February of 2024, Fox and her team discovered a correlation between accelerated adrenal puberty in firstborn daughters and high levels of prenatal stress in their mothers. Understanding how development may adaptively respond to stress contributes to our knowledge of the emotional and environmental factors that shape women’s lived experiences — a focus that has driven much of Fox’s work in this field.
The biological relationships among grandmothers, mothers and children have revealed insights about pregnancy and early development, but Fox’s work goes further by expanding our understanding of cognitive aging, chronic disease risk and the evolutionary logic of the human family. Federal funding makes this research possible, allowing her to collect biological samples and conduct interviews in new longitudinal cohorts, as well as to analyze large pre-existing datasets — work that is essential for answering questions about how evolution shapes human health and well-being.
