The demographic characteristics of human populations are clearly of major importance for any sociological understanding of human society.
Changes in the size and structure of population have a direct bearing on, for example, the availability of housing, education, health and employment. Despite these obvious connections between demography and sociology, it is perhaps surprising that the two disciplines have tended to develop as separate and distinct approaches to human society.
Although- the question of population intensity played an important part in early sociological theory and research, sociologists did not take the demographic features of society to be of central analytical significance in sociological explanation. One explanation of the neglect of demography by sociologists may lie in the fact that sociologists like T. Parsons came to equate an interest in the demography of society with a ‘biologising’ tendency in sociological theory.
Biological determinism attempts to employ the study of animal populations as the basis for the study of human groups, perceiving the latter in terms of basic laws of population growth in relation to fixed resources. While demographers were inclined to ignore the cultural and social factors which mediate between population and environment, sociologists have neglected population variables between society and environment
This mirror-image ignorance between demography and sociology has now changed fundamentally with recent developments in the social history of human populations which is centrally concerned with such questions as marriage practices, bestiary, family structure and generally with the impact of social conditions on fertility, mortality and migration.
Historical demography employs the method of family reconstitution in which parish records are used to study the major demographic events-births, deaths and marriages-in each family. The use of this method by, for example, the Annales School transformed sociologists’ understanding of the family.
In particular, it helped to destroy the myth of the extended family in pro-industrial Europe. Historical demography, especially under the impact of the Cambridge Centre for the study of population and history has made a major contribution to the reevaluate of conventional sociological perspectives on the family and social class, and the social aspects of population change.
This expansion in historical demography has consequently made important contributions to the sociological analysis of social change by improving our understanding of the relationship between population change, social structure and technological improvement.