Borgerhoff Mulder is a human behavioural ecologist, working on projects relating to life history, inequality, natural resource management and patterned cultural variation. She explores big “why” questions about our species: Why do people marry? What is the basis of gender roles in economic and social behaviour? Why has fertility dropped so radically in most parts of the world? How can people cooperate over natural resource management? Why is economic growth in the developing world not reducing inequality? 

She trained as a social anthropologist at the University of Edinburgh, working in journalism, teaching and museum archaeology before starting a doctoral program at Northwestern University, writing a dissertation on the behavioural, ecological and economic model to polygyny in rural Africa, a topic she has continued to explore throughout her academic life.