This explains somewhat.
Biodemography is a new branch of human (classical) demography concerned with understanding the complementary biological and demographic determinants of and interactions between the birth and death processes that shape individuals, cohorts and
populations. The biological component brings human demography under the unifying theoretical umbrella of
evolution, and the demographic component provides an analytical foundation for many of the principles upon which evolutionary theory rests including
fitness,
selection, structure, and change. Whereas biodemographers are concerned with birth and death processes as they relate to populations in general and to humans in particular, population biologists specializing in life history theory are interested in these processes only insofar as they relate to fitness and evolution.
For example, evolutionary biologists seldom focus on older, post-
reproductives because these individuals (it is typically argued) do not contribute to fitness. In contrast, biodemographers embrace research programs expressly designed to study individuals at ages beyond their reproductive years because information on these age classes will shed important light on
longevity and
aging. The biological and demographic components of biodemography are not hierarchical but reciprocal in that both are primary windows on the world and are thus synergistic, complementary and mutually informing.
Biodemography is unique in two respects.
First, it is one of a small number of key subdisciplines arising from the
social sciences that has embraced biology such as
evolutionary psychology and
neuroeconomics. However, unlike the others which focus more narrowly on biological sub-areas (
neurology) or concepts (evolution), biodemography has no explicit biological boundaries. As a consequence, it is a more all-encompassing interdisciplinary concept, but maintains deep biological roots.
Second, the hierarchical organizations that are inherent to both biology (cell, organ, individual) and demography (individual cohort, population) form a chain in which the individual serves as the link between the lower mechanistic levels, and the higher functional levels.
Biodemography is therefore ideally suited – serving as a “
looking glass” - to complement, engage and inform research on human aging through theory building using mathematical and
statistical modeling,
hypothesis testing using experimental methods, and coherence-seeking using genetics and evolutionary concepts.
