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The rapid growth of contemporary human foragers and steady decline of chimpanzees represent puzzling population paradoxes, as any species must exhibit near-stationary growth over much of their evolutionary history. We evaluate the conditions favoring zero population growth (ZPG) among 10 small-scale subsistence human populations and five wild chimpanzee groups according to four demographic scenarios: altered mean vital rates (i.e., fertility and mortality), vital rate stochasticity, vital rate covariance, and periodic catastrophes. Among most human populations, changing mean fertility or survivorship alone requires unprecedented alterations. Stochastic variance and covariance would similarly require major adjustment to achieve ZPG in most populations. Crashes could maintain ZPG in slow-growing populations but must be frequent and severe in fast-growing populations-more extreme than observed in the ethnographic record. A combination of vital rate alteration with catastrophes is the most realistic solution to the forager population paradox. ZPG in declining chimpanzees is more readily obtainable through reducing mortality and altering covariance. While some human populations may have hovered near ZPG under harsher conditions (e.g., violence or food shortage), modern Homo sapiens were equipped with the potential to rapidly colonize new habitats and likely experienced population fluctuations and local extinctions over evolutionary history., Competing Interests: The authors declare no conflict of interest.

To carry out their duties more effectively, health care professionals in the UAE often ask about the population structure and the main causes of mortality and morbidity in the country. This paper summarizes what is known about these topics drawing on secondary data sources that are available in the public domain, including census data, population estimates, births and deaths, proportionate mortality, age-standardized mortality rates and disability adjusted life-years. There are inconsistencies and flaws in some of this data which this paper will highlight and attempt to explain. Since 2005, the UAE population has grown substantially owing to high natural growth and high net inward migration and is currently estimated to be about 8.2million. In 2008, injuries, heart disease, neoplasms and cerebrovascular disease accounted for 57% of deaths, and this is well known. Less is reported about the risk of death, disease, injury and disability. The population of the UAE is diverse, and there are variations in mortality and morbidity risk by age-group, sex and nationality. The authors recommend improvements in the timeliness, completeness and consistency of data. They conclude that better data will encourage more analysis which will generate health intelligence leading to health improvement for the UAE population., (Copyright © 2012 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.)

The invention of agriculture is widely assumed to have driven recent human population growth. However, direct genetic evidence for population growth after independent agricultural origins has been elusive. We estimated population sizes through time from a set of globally distributed whole mitochondrial genomes, after separating lineages associated with agricultural populations from those associated with hunter-gatherers. The coalescent-based analysis revealed strong evidence for distinct demographic expansions in Europe, southeastern Asia, and sub-Saharan Africa within the past 10,000 y. Estimates of the timing of population growth based on genetic data correspond neatly to dates for the initial origins of agriculture derived from archaeological evidence. Comparisons of rates of population growth through time reveal that the invention of agriculture facilitated a fivefold increase in population growth relative to more ancient expansions of hunter-gatherers.

To review, the four broad dimensions of any complex human problem, including climate change, are the human population, economics, culture, and environment. These dimensions interact with one another in all directions and on many time-scales. From 2010 to 2050, the human population is likely to grow bigger, more slowly, older, and more urban. It is projected that by 2050 more than 2.6 billion people (almost 94% of global urban growth) will be added to the urban population in today's developing countries. That works out to 1.26 million additional urban people in today's developing countries every week from 2010 to 2050. Humans alter the climate by emitting greenhouse gases, by altering planetary albedo, and by altering atmospheric components. Between 1900 and 2000, humans' emissions of carbon into the atmosphere increased fifteenfold, while the numbers of people increased less than fourfold. Population growth alone, with constant rates of emissions per person, could not account for the increase in the carbon emissions to the atmosphere. The world economy grew sixteenfold in the twentieth century, accompanied by enormous increases in the burning of gas, oil, and coal. In the last quarter of the twentieth century, population grew much faster in developing countries than in high-income countries, and, compared with population growth, the growth of carbon emissions to the atmosphere was even faster in developing countries than in high-income countries. The ratio of emissions-to-population growth rates was 2.8 in developing countries compared with 1.6 in high-income countries. Emissions of CO2 and other greenhouse gases are influenced by the sizes and density of settlements, the sizes of households, and the ages of householders. Between 2010 and 2050, these demographic factors are anticipated to change substantially. Therefore demography will play a substantial role in the dynamics of climate changes. Climate changes affect many aspects of the living environment, including human settlements, food production, and diseases. These changes will affect poor people more severely than rich, and poor nations more severely than rich. Yet not enough is known to predict quantitatively many details that will matter enormously to future people and other species. Three kinds of responses are related to demographic issues that affect climate changes: universal secondary education, voluntary contraception and maternal health services, and smarter urban design and construction. These responses may prevent, reduce, or ameliorate the impacts of climate changes. They are as relevant to rich countries as to poor, though in ways that are as different as are rich countries and poor. They are desirable in their own right because they improve the lives of the people they affect directly; and they are desirable for their beneficial effects on the larger society and globe. They are effective responses to the twin challenges of reducing poverty and reducing greenhouse gas emissions.

The changing residential population of New York State requires continued monitoring if health practitioners are to maintain an awareness of the individuals in their community. A review of federal agency reports provides a general overview of state and national demographic and health factor characteristics.

We study a model of economic growth in which an exogenously changing population enters in the objective function under total utilitarianism and into the state dynamics as the labor input to the production function. We consider an arbitrary population growth until it reaches a critical level (resp. saturation level) at which point it starts growing exponentially (resp. it stops growing altogether). This requires population as well as capital as state variables. By letting the population variable serve as the surrogate of time, we are still able to depict the optimal path and its convergence to the long-run equilibrium on a two-dimensional phase diagram. The phase diagram consists of a transient curve that reaches the classical curve associated with a positive exponential growth at the time the population reaches the critical level. In the case of an asymptotic population saturation, we expect the transient curve to approach the equilibrium as the population approaches its saturation level. Finally, we characterize the approaches to the classical curve and to the equilibrium.

We compare the age and sex structure of China's 2000 population census to an estimate of that structure derived from a projection from the 1990 census. Based on China's own official estimates of demographic change, our intercensal analysis indicates a shortfall in enumeration of more than a quarter of all children under age 5 and an eighth of those between 5 and 9, a total of nearly 37 million children missing in the 2000 census. We show that the shortfall is primarily due to underreporting of children in the census. Sex differences in child underreporting were fairly minor. Child underreporting in China is not unprecedented, but child underreporting rates in 2000 were about triple those of previous censuses. We attribute the increase primarily to policy changes beginning in the early 1990s that held officials at all jurisdictional levels personally responsible for enforcing birth quotas.

This paper reviews historical and projected trends in world population numbers, and the underlying determinants of those trends. Whereas the world's population has shown little change over most of its one million-year history, the past 200 years have witnessed dramatic changes in fertility, mortality and population growth rates. Recent decades, in particular, have seen unprecedented demographic events, with more people added to the world's population in the past 50 years than in the preceding million. The demographic impact of HIV/AIDS, selective as it is to young adults and infants, is also unprecedented, with life expectancy among some populations reduced by almost 20 years. As we approach the end of the 20th century, further demographic changes are underway with, for the first time in recent human history, a slowing down of world population growth. Nonetheless, world population is projected to grow from 6 billion currently to about 9.4 billion by 2050 (medium fertility assumption), with ageing emerging as the most pressing demographic issue facing humanity in the millenium.

This paper describes what the Wellcome Trust has done and aims to do through its population initiative. The Trust is required to spend its funds to improve the physical welfare of mankind, and in this context there can be no more important issue than the rapid changes that are occurring in the human population. The Trust's first involvement was to help fund the New Delhi population summit covered by the world's scientific academics in 1993 and, following discussions with authorities in the field, initiated its funding programme in 1995. Through this programme, the Trust hopes to bring about improved understanding of the relationship between reproductive health, population growth, and sustainable development and create cadres of high quality research scientists in relevant disciplines. Uniquely, funding is available under this programme to suitably qualified applicants from any country other than the USA.

The author reviews the major demographic trends of the twentieth century in Bulgaria. "The results from the analysis show that the demographic development of Bulgaria especially in the years after 1950 differs very little from the developed, urbanized and industrialized countries. The common features are: development towards [replacement] fertility, [lower mortality rates], zero natural growth [leading] to an increasing life expectancy at birth, [and] population ageing...." (SUMMARY IN ENG AND RUS), (excerpt)

Existing methods for estimating population parameters in settings of data deficiency do not provide techniques for analysis of commonly available longitudinal data. In setting where complete population data is unavailable, longitudinal data recorded for only a subset of the total population are often available (e.g., event registers, genealogies). In this article we present and evaluate models which derive population parameters for the population subgroup underlying such longitudinal data. Using the distribution of individual times until first recorded event within a measurement interval, population parameters are estimated which provide basic denominator data for analyzing event occurrence. The models which we derive are especially suited to records which may include migration and population growth trends. The use of the models is demonstrated and evaluated through an application to genealogical records for a nineteenth-century population. Possible extensions of these models and their major limitations are also discussed.