Research Interests

As a demographer I have studied the determinants, consequences, and policy implications of the contemporary global demographic transition. This work has focused on the behavioral, socioeconomic, and programmatic determinants of fertility declines in the developing world. These changes in reproductive behavior have been accelerated by family planning programs that were implemented in many countries in response to concern about the adverse consequences of rapid population growth. An analysis of population projections for the twenty-first century indicates that population momentum is now a more important cause of future growth than high fertility. This finding calls for new and different policy responses. A set of related studies has quantified the contribution of population growth to global warming and to rising demand for food. Recently I have examined the determinants of very low fertility in the industrialized world, where population decline and rapid aging are expected to occur over the next few decades. Widely available fertility statistics were found to contain a "tempo" distortion due to the rising mean age at childbearing. This result implies that women are having higher fertility than conventional statistics suggest. A modest upturn in fertility in high-income countries with low birthrates is therefore possible.

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Primary Section

Section 53: Social and Political Sciences

Secondary Section

Section 64: Human Environmental Sciences