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A general model describing the evolution of levels of fertility and mortality over time. It was devised with particular reference to the experience of developed countries which have passed through the process of industrialization and urbanization, and it has attracted considerable criticism as a general model. The first formulation in the demographic literature was by Warren Thompson in 1929, with further significant restatements by Adolphe Landry in 1934 and Frank Notestein in 1945 (Kirk, 1996).
The model suggests four highly stylized phases in the process (see figure). In the first, high stationary phase, both birth and death rates are high. Deaths, due to famines, diseases or wars, are said to be the most important influence on population growth, which tends to be at a low level. In the second, early expanding phase, the population begins to grow, as a result of a stable birth rate and a rapidly declining death rate. The latter falls as a result of improved nutrition, sanitation and medicine. The third, late expanding phase, is characterized by a slowing in the growth rate as the death rate stabilizes at a low level and the birth rate declines. This decline may be associated with the growth of an urban/industrial society, with changing attitudes to family formation, with changing patterns of marriage and with the use of contraceptive methods. In the final, low stationary phase birth and death rates have stabilized at a low level, population growth is very slow, and the birth rate is more likely to fluctuate than the death rate.
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Demographic transition (Haggett, 1975)
There is much variety in the way in which demographic transition applies to individual countries and, indeed, widespread doubt about the model\'s validity and applicability. Most countries of Europe, North America and the rest of the developed world now have very low rates of fertility and mortality, with low levels of population growth, for example, whereas by contrast, many countries of the Third World are experiencing high rates of growth, as the decline in mortality has not been fully matched by a reduction in fertility, though the latter is declining in many countries. Great care must be taken in applying the model of demographic transition to individual countries, however: recent research has shown that the first stage of the model is rather oversimplified for the currently developed world, for example, with fluctuating nuptiality and fertility having a greater influence on population growth than previously recognized. The work of the Princeton European Fertility Project (Coale and Watkins, 1986;Watkins, 1991) has demonstrated the complexity of fertility decline in the nineteenth and twentieth centuries, in terms of its geography, periodicity and causality. In addition, post-1945 fluctuations in the birth rates of the developed world are more complex than the model implies, as the role of marriage and attitudes to family formation have proved more variable, for example amongst European countries, than envisaged in the model. Moreover, it is far from certain that the currently developing world will follow the form of transition depicted in the figure (see, for example, Leete, 1996). Demographic transition remains an important, if contested, idea in population geography and geographers have sought to match it with a similar model of the mobility transition (see migration) in order to understand long-term trends in population change. (PEO)
References Coale, A.J. and Watkins, S.C., eds, 1986: The decline of fertility in Europe. Princeton: Princeton University Press. Haggett, P. 1983: Geography: a modern synthesis, rev. 3rd edn. New York and London: Harper and Row. Kirk, D. 1996: Demographic transition theory, Population Studies 50, 3: 361-87. Leete, R. 1996: Malaysia\'s demographic transition: rapid development, culture and politics. Kuala Lumpur and Oxford: Oxford University Press. Watkins, S.C. 1991: From provinces into nations. Demographic integration in western Europe, 1870-1960. Princeton, New Jersey: Princeton University Press.
Suggested Reading Chesnais, J.-C. 1992: Demographic transition. Stages, patterns and economic implications, trans. by P. Kreager Oxford: Oxford University Press. Davis, K., Bernstam, M.S., and R. Ricardo-Campbell, eds,1986:Below replacement fertility in industrial societies. Causes, consequences, policies. (Supplement to Population and Development Review, vol. 12). New York: The Population Council. Day, L.H. 1992: The future of low-birthrate populations. London and New York: Routledge. Livi-Bacci, M. 1997: A concise history of world population, 2nd edn. Oxford: Blackwell. Szreter, S. 1993: The idea of the demographic transition and the study of fertility change: a critical intellectual history. Population and Development Review 19 (4): 659-701. Woods, R. and P. Rees, 1986: Population structures and models. Developments in spatial demography. London: Allen and Unwin, ch. 3. |
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