Biodemography, the study of biological aspects of demographic processes and relationships, is one of a small number of subdisciplines arising from the social sciences that has embraced biology (e.g., evolutionary psychology, neuroeconomics). The field can be divided into two moderately overlapping subfields. The first is biological biodemography. Here researchers bring experimental methods (i.e., using model organisms such as fruit flies and laboratory rodents) and life history, ecological and evolutionary theories to bear on basic demographic questions pertaining to health, aging, and lifespan. The second subarea of biodemography is biomedical biodemography where the focus is primarily on the analysis of survey data on human health, epidemiology, and genetics. The biological measurements derived from these surveys are used as covariates in demographic analyses in much the same way that social and economic information is used.