The demography of Tristan da Cunha

Abstract The eruption of the volcano on Tristan da Cunha in 1961 and the subsequent arrival of the island population in the United Kingdom provided a unique opportunity for studying the health of this formerly isolated community. During their stay, while the facilities and services of modern medicine were made available to them, investigations of many facets of their general biology were made under the auspices of the Medical Research Council, co-ordinated by Dr. H. E. Lewis. Analysis of their demographic history was essential to understand many features of their disease pattern, and the results of this analysis are presented here. They are of interest in that they not only show some consistent trends in the common variables of demography, but also demonstrate biological principles, some perhaps for the first time in man, which may be fundamental in the process of colonization as a biological phenomenon, e.g. the initial difficulty of establishment of a population in a new area, the curious demographic structure that may emerge in its earliest years, the bottleneck effect of population-size reduction, the founder principle.     

Countries with Rapid Population Growth and Resource Constraints: Issues of Food,Agriculture, and Development

Recent long‐term demographic projections suggest a fast deceleration of global population growth and the eventual peaking of world population later in this century at about 9.2 billion, roughly 50 percent above the present level. Some low‐income and food‐insecure countries, however, have projected populations in 2050 that are multiples of present ones. In some of these countries agriculture must play a leading role in their development efforts because they have high economic dependence on that sector. For those among them that have scarce agricultural resources, a prima facie case can be made that the high population growth rates projected may not be compatible with the development potential offered by such resources. Their demographic projections may need to be revisited, taking into account such inadequate potential. The global demographic slowdown notwithstanding, the “population explosion”‐related issues pertaining to food and agriculture will not become irrelevant but will be become increasingly localized.     

Implications of demographic change for civil society in Germany

Germany is currently beginning to become aware of the consequences of a process of demographic change, initially triggered by extremely low levels of fertility. The population recently started to decline, the demographic dividend is coming to an end and the ageing of society accelerates. Particularly places in peripheral regions are already seriously affected by this process which will increase in pace and spread spatially. Shrinking and ageing populations are associated with a declining purchasing power as well as fewer local tax revenues for public and private services and infrastructure. The population necessary to maintain and economically justify the provision of public services and infrastructure at the current level will in many cases shrink below required thresholds. Commercial services will probably also continue to diminish at such places. Volunteer organizations may provide some of the services which the local administrations can no longer afford to provide and thus strengthen civil society and social cohesion. But can this be an option for communities with a shrinking and ageing population in which qualified younger people are lost through out-migration? The paper presents a new projection of the future demographic capacity for volunteer organizations and concludes that the decay of demographic capacity will affect most regions and sectors of civil society. The loss will be most prominent in remote areas with low population density and in sectors where the need to compensate for declining public services and infrastructure will be highest.     

Population trends and population policy in Ceylon

The population of Ceylon has many. features in common with other Asian countries. Ceylon has, however, the distinction of an unusual wealth of demographic data. The study of many problems of general interest to Asia may thus be made for Ceylon, and the conclusions in part extended to other Asian countries.     

Fertility and mortality in Finland since 1750

Summary In this paper the development of fertility and mortality in Finland, and their interrelations with each other and with economic factors is discussed. An analysis by individual years shows that rises and falls in mortality and fertility rates did not always coincide with poor and good harvests. Fertility in Finland decreased slightly at the turn of the eighteenth and nineteenth centuries, but fell sharply over the period 1876-1925. This fall corresponded closely to changes in the death rate, especially for infants, and appears to justify the conclusion that the changes were connected. These population shifts have been called the first and second demographic transitions, of which the latter was the more dramatic. Factors tending to reduce mortality among infants and in other age groups during the second demographic transition are obvious; those underlying the first demographic transition are less clear. In this connection, the importance of breast feeding and campaigns designed to favour the practice are stressed. These helped to reduce infant mortality and were one of the main reasons for the first demographic transition. Finnish material also suggests that some kind of family planning existed during the pre-industrial period; it is only by making this assumption that the various figures can be made compatible.     

One step back in understanding racial differences in birth weight

In recognition of the biological and social connections in demographic processes, demographers have integrated biological factors into their models of population variation. This new effort has tended to focus on the analysis of fertility and mortality. Edwin J.C.G. van den Oord and David C. Rowe's article, "Racial Differences in Birth Health Risk: A Quantitative Genetic Approach," published in the August 2000 issue of Demography, is part of this effort. These authors use race as a proxy for genetic variation, which subverts even the most positive attempts to understand the impact of genetic variation on demographic processes. The authors' statistical results restate their anachronistic theory of race using latent variables that are not open to empirical testing. Although new data increase the opportunities for the examination of the relationship between biology and demographic processes researchers must be vigilant not to commit the errors of the past by misusing race as a variable.     

The UN Population Division on Replacement Migration

The most salient demographic trend pictured by the influential set of population projections prepared by the Population Division of the United Nations (a unit in the UN's Department of Economic and Social Affairs) is the continuing substantial increase—albeit at a declining rate—of the global population during the coming decades. According to the “medium” variant of the most recent (1998) revision of these projections, between 2000 and 2050 the expected net addition to the size of the world population will be some 2.85 billion, a figure larger than that of the total world population as recently as the mid‐1950s. All of this increase will occur in the countries currently classified as less developed; in fact, as a result of their anticipated persistent below‐replacement levels of fertility, the more developed regions as a whole would experience declining population size beginning about 2020, and would register a net population loss of some 33 million between 2000 and 2050. A report prepared by the UN Population Division and released on 21 March 2000 addresses some of the implications of the changes in population size and age structure that low‐fertility countries will be likely to experience. The 143‐page report, issued under the eyecatching title Replacement Migration: Is It a Solution to Declining and Ageing Populations?, highlights the expected magnitude of these changes by the imaginative device of answering three hypothetical questions. The answer to each of these questions is predicated on the assumption that some specified demographic feature of various country or regional populations would be maintained at the highest level that feature would exhibit, in the absence of international migration, in the United Nations' medium population projections (as revised in 1998) during the period 1995–2050. The selected demographic features are total population size, the size of the working‐age population (15–64 years), and the so‐called potential support ratio: the ratio of the working‐age population to the old‐age population (65 years and older). The illustrative device chosen for accomplishing the specified feats of preserving the selected demographic parameters (i.e., keeping them unchanged up to 2050 once their highest value is attained) is international migration. Hence the term “replacement migration.” Given the low levels of fertility and mortality now prevailing in the more developed world (and specifically in the eight countries and the two overlapping regions for which the numerical answers to the above questions are presented in the report), and given the expected future evolution of fertility and mortality incorporated in the UN population projections, the results are predictably startling. The magnitudes of the requisite compensatory migration streams tend to be huge relative both to current net inmigration flows and to the size of the receiving populations; least so in the case of the migration needed to maintain total population size and most so in the case of migration needed to counterbalance population aging by maintaining the support ratio. Reflecting its relatively high fertility and its past and current record of receiving a large influx of international migrants, the United States is a partial exception to this rule. But even for the US to maintain the support ratio at its highest—year 1995—level of 5.21 would require increasing net inmigration more than tenfold. The country, the report states, would have to receive 593 million immigrants between 1995 and 2050, or a yearly average of 10.8 million. The extreme case is the Republic of Korea, where the exercise calls for maintaining a support ratio of 12.6. To satisfy this requirement, Korea, with a current population of some 47 million, would need 5.1 billion immigrants between 1995 and 2050, or an average of 94 million immigrants per year. (In the calculations, the age and sex distribution of migrants is assumed to be the same as that observed in the past in the main immigration countries. The fertility and mortality of immigrants are assumed to be identical with those of the receiving population.) The “Executive Summary” of the report is reproduced below, with the permission of the United Nations. Chapters of the full report set out the issues that prompted the exercise; provide a selective review of the literature; explain the methodology and the assumptions underlying the calculations; and present the detailed results for the eight countries and two regions selected for illustrative purposes. A brief discussion of the implications of the findings concludes the report. As is evident even from the figures just cited, immigration is shown to be at best a modest potential palliative to whatever problems declining population size and population aging are likely to pose to low‐fertility countries. The calculations, however, vividly illustrate that demographic changes will profoundly affect society and the economy, and will require adjustments that remain inadequately appreciated and assessed. The criteria specified in the UN calculations—maintenance of particular demographic parameters at a peak value—of course do not necessarily have special normative significance. Past demographic changes, with respect notably to the age distribution as well as population size, have been substantial, yet they have been successfully accommodated under circumstances of growing prosperity in many countries. But the past may be an imperfect guide in confronting the evolving dynamics of low‐fertility populations. As the report convincingly states, the new demographic challenges will require comprehensive reassessments of many established economic and social policies and programs.     

Polish education in the crisis decade--the testimony of population census

"The purpose of this essay is to offer information on the links that exist between...demographic growth, education and the [labor force] in Poland, as revealed in past population censuses...taken in 1978 and 1988...." The effect of education on occupational status is discussed, and some projections for Poland's educational and employment sectors are made.     

Africa's expanding population: old problems,new policies

Sub-Saharan Africa faces an historic challenge: to achieve economic and social progress while experiencing extraordinary population growth. With an estimated 1989 population of 512 million, the 42 countries of sub-Saharan Africa have the highest birth and death rates of any major world region. While death rates have fallen since the 1960s, persistently high birth rates yield annual growth rates above 3% in many countries. The United Nations projects that the region's population will increase 2.7 times by 2025--to 1.4 billion. Throughout the region, population has outstripped economic growth since the mid-1970s. In addition, many African countries are experiencing an epidemic of AIDS (Acquired Immunodeficiency Syndrome). The extent and demographic impact of the epidemic still are unknown, but disturbing social and political effects are already being felt. The region's population growth will slow only when African couples begin to have fewer children. The average number of children per woman ranges from 6 to 8 for most countries. The Africans' preference for large families is deeply rooted in the culture and fed by the perceived economic benefits they receive from their children. Economic stagnation during the 1980s prompted many national governments to recognize that rapid population growth was hindering their socioeconomic development. The political climate has shifted away from pronatalist or laissez-faire attitudes toward official policies to slow population growth. The policy formation process--detailed here for 4 countries (Zambia, Nigeria, Zaire, and Liberia)--is ponderous and beset with political and bureaucratic pitfalls, However, policy shifts in more and more countries combined with evidence of increased contraceptive use and fertility downturns in a few countries give some hope that the region's extraordinary population growth may have peaked and will start a descent. Whatever the case, the decade of the 1990s will be crucial for the future of sub-Saharan Africa.     

Chinese genealogies as a source for demographic research: A further assessment of their reliability and biases

Genealogy is the written record of family or lineage members descended from a common ancestor or ancestors. These materials have long been used by demographers in their investigation of past demographic behaviour. Most available genealogies, however, are the records of members of surviving patrilineages. Among the many reasons why these patrilineages have avoided extinction is the fact that they have usually experienced favourable demographic conditions.. In consequence, their genealogies could be a biased data source if used in the study of the history of the whole population. This paper examines this issue, using evidence on the historical experience of the Chinese population and computer micro-simulation.     

Biological and social determinants of body size across the life span

The accuracy of demographic models designed to project future trends of population-level health and disease can be improved by incorporating biological data. One barrier to this process are quantitative characteristics of the data themselves. Biological data are characteristically time-dependent phenomena that behave in a nonlinear fashion. To develop accurate projections of the morbidity, disability, and mortality experience among future cohorts in late life, research needs to focus on development of models that create the opportunity to distinguish all-or-none, boundaries, and latency aspects of biological factors driving demographic phenomena, development of methods to identify time-dependent effects, and development of genetically informative samples. This presentation focuses on the biology of adult body size, its behavior as a variable in statistical analyses, and strategies for the incorporation of this variable into demographic models of population aging in the United States. First, several examples of generally observed quantitative characteristics of biological variables are reviewed. To illustrate the nonlinear character of biological data, three general patterns of change with aging are presented. Next, issues concerning the measurement of body size are discussed. Scenarios describing body size over the adult life span are described. By the end of this process, recommendations for starting a dialogue between researchers interested in biological endpoints (individual weight change, disease risk) and those interested in demographic outcomes (population-level disease and disability issues) using body size will be presented.     

Fertility decline and female chances of marriage in Malaya

A feature of the demographic pattern of post-World War II Malaya has been its high rate of natural growth, which reached 31/2 per cent per annum in the mid-1950s. However, the average age at marriage of the female population has been rising for most of this period, and since 1956 there has been a considerable and sustained fall in the birth rate.

In this paper simple models are developed to show that in a closed population a continuing high rate of population growth is incompatible with a pattern of universal female marriage, monogamy and a culturally imposed age difference of considerable size between spouses. The demonstration provided by the models is then offered as at least a partial explanation of the fertility and female marriage trends in contemporary Malaya. Discrepancies between the population of Malaya and the models have to be taken into account. A pattern of polygamous and unstable marriage does exist amongst the Malaysians and, to a much lesser extent, in the Chinese community. Furthermore, recent years have witnessed the passing of the large surplus of single males built up in the Chinese sector of the population during the years oflarge scale immigration. Such a transition is well under way in the Indian community too.

It is suggested that a substantial average age gap between spouses may be an aspect of many contemporary societies which reacts against the persistence of extremely high rates of natural increase. Even where demographic pressures in the ‘marriage market’ act towards a lessening of this gap, there is a cultural lag, during which period many females are forced to marry late or not at all.

Most of the study was made on a pan-Malayan basis (i.e. combining the Federation of Malaya and the State of Singapore) to achieve comparability with earlier censuses and as a recognition that with unrestricted migration between these areas they still form a single demographic unit. The terms Malaya and Malayans will be used when referring to this area or its inhabitants. The so-called major races of the country are Malaysians, Chinese and Indians. The first will be used in accordance with the census definition to cover the indigenous inhabitants of Malaya or the Malay Archipelago (Indonesia, British Borneo and the Philippines). As most of these people are either indigenous or have been in Malays for some generations they are usually called Malays (except for the aborigines). However, the all-embracing census term will be used here. Indians, in conformity with most local usage, will be used for the groups classified as Indians and Pakistanis at the 1957 censuses of the Federation of Malaya and Singapore. The group was very small.     

The demise of the American Indios

This symposium takes as its point of departure two books by Massimo Livi Bacci, Conquest and El Dorado in the Marshes, published in English in 2008 and 2010. Livi Bacci assesses widely varying estimates of the demographic dimensions of the collapse of the Native populations following their contact with Europeans and elucidates the proximate causes of that catastrophe. Drawing on models that combine production potential with demography, environment, and technology, Shripad Tuljapurkar discusses analogous historical experiences of the populations of Polynesia and the social transformation they entailed. David S. Reher argues that explanations of the estimated demographic dynamics need to take into account the negative fertility responses of the Indigenous population to the disruption of their traditional way of life. Focusing on the biological aspects of immunity to diseases such as smallpox, Andrew Noymer demonstrates that infectious diseases alone could not account for the Indios' population collapse. The contributions to this symposium are based on presentations at a session at the 2010 annual meeting of the Population Association of America, held in Dallas, Texas, that examined the demographic consequences of the Spanish conquest of the Caribbean region and of South America in light of the two books.     

Advocating "one couple with one child" being an optimal choice]

Zero population growth within the next 5 years in China would be reached only if many couples were not allowed to have their own child. On the other hand, if every couple were allowed to have 2 children China's population would reach 1500 million within the next 50 years. It seems advisable to advocate the "1 couple 1 child" idea; couples will have to keep in mind both the national interest and the communist ideology; social welfare to assure good living conditions for the old people will relieve the worries of parents with 1 child only. Most people are willing to follow this decision made by the Communist Party; many people declare their willingness to stick by this rule during their wedding ceremony; many couples send back their permit to have a second child, and many women choose abortion when pregnant with a second permitted pregnancy. By the end of 1979 the proportion of "1 couple 1 child" couples was 90% in many large cities; people realize that the practice of "1 couple 1 child" is the best assurance for the future of the country and of their children. This policy will not result in aging of the population, lack of manpower and shortage of soldiers; even if birth rate were 1% in 1985 the proportion of older people for the next 25 years will still be lower than that in European countries. The problem of aging of the population will not occur in this century, and population policies can always be adjusted when needed. Today's problem is to control population through the "1 couple 1 child" policy, even if it may result in many lonely old people, which is a lesser problem than too many people. Even if China has reduced its population growth by 10 million births each year from 1970 to 1979, the necessity to control population growth is still present, in the interest of the country and economic development.     

The Biodemography of Variation in Human Frailty

A population is composed of individuals who are heterogeneous in their susceptibility to death and disease. This heterogeneity is reflected in the age-specific incidence or mortality (hazard) function. This variation has typically been hidden--that is, not measured directly--and has generally been modeled in a purely empirical statistical way, because there is no theory in demography for the distribution of frailty. A substantial fraction of variation in frailty, however, has an underlying genetic basis, for which there is a formal theory. This theory, based on evolutionary biology and on the nature of mendelian transmission, provides prior constraints on the distribution of variation in the population as well as providing methods for identifying genes involved in many important diseases. The accumulating effects of environmental exposures with age are another major component of variation in frailty. In some important instances, this variation and its effect on the age-specific hazard function can also be understood in terms of cause-specific biological processes. These biological considerations may enable demographers to model frailty, and thus mortality, in a better way.     

Helpless Dependents or Active Independents: A Cluster Analysis of Elders in China

The current study aimed to gain a better understanding of Chinese seniors’ demographic information as well as their attitudes toward old-age support as an indicator for their subjective well-being related to their retirement preparation. Particularly, the variation of demographic and attitudinal characteristics within the population was examined. The data was based on a sample of the Chinese senior population, aged 60 and over in 2006 from 20 provinces and metropolitan areas in China. A two-step cluster analysis was used in the current study and the auto-clustering algorithm indicated a two-cluster solution. Both demographic information and attitudinal responses were used for the clusters. The results showed that Chinese seniors’ attitudinal and behavioral traits were relevant to the classification with regard to their retirement preparedness. The current study demonstrated that Chinese seniors were a heterogeneous group that could be divided into two basic, distinct segments, namely, helpless dependents and active independents. Each different group of seniors may raise different key issues in meeting their needs for retirement management.     

Age structure,growth, attrition and accession: A new synthesis

This paper shows that each equation describing relationships among demographic parameters in a stable population is a special case of a similar and equally simple equation that applies to any closed population and demonstrates some implications of these new equations for demographic theory and practice. Much of formal demography deals with functions that pertain to individuals passing through life, or to a stationary population in which births of individuals are evenly distributed over time. These functions include life expectancy, probabilities of survival, net and gross reproduction rates, expected years spent in various states and the probability that certain events will occur in the course of life. The stable population model permits the translation of population structure or processes in a more general type of population, with constant growth rates, back into equivalent populations for a stationary population. The method for translation developed in this paper, requiring only a set of age-specific growth rates is even more general, applying to any population. Age specific growth rates may also be useful for performing reverse translations, between a population's life table and its birth rate or its age distribution. Tables of numbers of females by single years of age in Sweden are used to illustrate applications. Tables summarize the basic relations among certain functions in a stationary population, a stable population and any population. Applications of new equations, particularly to demographic estimation of mortality, fertility and migration, from incomplete data, are described. Some other applications include; the 2 sex problem, increment decrement tables, convergence of population to its stable form, and cyclical changes in vital rates. Stable population models will continue to demonstrate long term implications of changes in mortality and fertility. However, in demographic estimation and measurement, new procedures will support most of those based on stable assumptions.     

A demographic history of the Indo-Dutch population, 1930–2001

Indonesia was a Dutch colony until 1949. In the aftermath of World War II and the independence of the former Dutch East Indies, many people migrated from Indonesia to the Netherlands or other Western countries. This migrant population, known as the Indo-Dutch population, consists of Europeans, Asians, and persons of mixed European-Asian blood. These groups have all associated themselves with and experienced the colonial culture of the former Dutch Indies, and have carried this cultural experience elsewhere through migration. This paper provides a demographic history of the Indo-Dutch population, using a variety of data sources and methods. Starting from the population of ‘Europeans’ according to the 1930 census of the Dutch Indies, a demographic projection is made covering the period 1930–2001. By the beginning of 2001, the estimated number of Indo-Dutch persons is 582,000, including the second generation. Of these 582,000, an estimated 458,000 are living in the Netherlands and 124,000 elsewhere. The composition by age, sex and generation very clearly reflects the demographic history of the population.     

人口转变的经济增长效应研究新进展：一个综述

关于人口转变对于经济增长的效应研究由来已久,但是研究大多只考虑了人口数量和人口增长率对于经济增长的效应。近二十年来,许多经济学家在揭示“东亚奇迹”和中国经济腾飞等一系列经济现象的原因时。发现了人口年龄结构对于经济增长的重要贡献,并提出了“人口红利”的概念以解释经济发展。本文将具体介绍近二十年来理论界对于人口转变影响经济增长的相关机制的研究以及经验分析。并对这些研究的政策含义和有待深入研究的问题作出简要评述。