The Earth’s Human Population- Growth and Poverty
The estimated number of individuals of the species Homo sapiens sapiens is a little over 6 billion today. However, the human population on Earth has not always been the same. It is very difficult to estimate the population trends for our prehistoric ancestors. It is assumed that the first billion mark was only reached at the turn of the 18th century. Since then, the growth rate has been ever faster. The number of people increased by five billion over the 19th and 20th centuries. While the world had to wait several tens of thousands of years for the first billion humans, the second billion arrived in just 130 years; the third one, in 30; the fourth one, in 14; the fifth one, in 13; and the latest, sixth billion arrived in just 12 years by 1999.
Most animal populations grow (or shrink) depending on the availability of food sources, shelter, breeding partners, disease rates, etc. The human population, on the other hand, seems to ignore some of the ecological rules. At present, the fastest population growth occurs in countries and regions where food availability is lower, opportunities for shelter are fewer, and diseases abound. This paradox is the result of a combination of many factors.
The growth of any population depends crucially on two factors: natality (the birth rate) and mortality (death rate). Since the first population growth records in the 19th century, both natality and mortality seem to have decreased. Thanks to the improving care for the newborn, improvements in hygiene and healthcare, however, mortality has been decreasing at a much faster rate than natality, meaning that the increment (difference between natality and mortality) is increasing. This phenomenon does not occur equally throughout the world. Some countries have already experienced a peak in their population growth, while the population keeps growing in others.
The so-called demographic transformation (demographic transition, demographic revolution) is one of the basic mechanisms driving human population dynamics. Countries in which natality and mortality have nearly evened out (where zero population growth is reached) are developed industrial countries with high quality of medical care and a system of varied social allowances (pensions, unemployment benefits, insurance, etc.), a high degree of women’s employment and good education. These countries, referred to as the ‘wealthy North’, have experienced demographic transformation and are characterised by a long-term decrease in the number of children per family, increasing age and social roles (including employment) of mothers, and changing social environments. Countries that have undergone the demographic transformation show low birth and death rates.
Some countries, nevertheless, have not completed the transformation yet. They are characterised by relatively low death rates (largely thanks to better availability of cheap basic medicines and certain improvements in medical care), but relatively high birth rates persist. Women’s position is understood as that of child-bearer and their employment opportunities are low. Traditions and livelihoods require many children per family and aversion to family planning and contraception is common in many African, Asian and Latin American countries. Presently, it is very difficult to determine when all the world’s countries are going to experience demographic transformation and thus, when the Earth’s human population will stabilise.
Population Growth and Poverty
To state that the world’s population is growing is a huge oversimplification of current affairs: an unprecedented demographic change is taking place world-wide. The enormous expansion of populations in developing countries is in sharp contrast to the situation in economically developed areas, where people tend to live longer and be healthier, women bear fewer children and the numbers of immigrants arriving in search for better livelihoods are increasing. Nonetheless, any discussion of global trends is misleading unless it takes into consideration the massive contrast between the world’s regions, outlined above. The current poorest regions in Africa, Asia and Latin America have rapidly growing young populations, while the developed rich countries of Europe, North America and Japan show zero or even negative growth with rapidly ageing populations. As a result of this, most of the population increment will be concentrated in the developing countries, where four-fifths of the entire current world’s population live. The estimated population growth in the developing countries for 2000-2025 (4.87-6.72 billion) is essentially equal to the record-breaking increase in the final quarter of the last century. The historically unprecedented population explosion in the poorest countries of the world will continue unabated.
The effect of the demographic characteristics on the quality of human life has been debated for centuries. When the modern-day human population expansion started in the 18th century, Thomas Robert Malthus maintained that the growth would be limited by food scarcity. However, the world’s population grew much faster than Malthus predicted, and it is a fact that the human nutrition has improved overall. Nevertheless, immense regional and societal differences exist globally in food availability and quality. The high nutrition quality in the wealthy North is in sharp contrast to the untenable situation in many parts of the impoverished South. Poverty is the main cause of hunger and malnutrition; population growth, in turn, is the main cause of the poverty. This relation is embodied by two mechanisms:
(1) Rapid population growth leads to younger population. Over one half of these populations are currently under the employment age limit. These young people need feeding, housing, clothing and educating, but are non-productive (in the official economy, at least), resulting in a significant burden to the economy.
(2) Rapid population growth results in a huge demand for new jobs. The large numbers of applicants for limited numbers of jobs push down wages, which is another cause of poverty and inequality. Unemployment is high in developing countries, and those who are employed receive wages which are hardly sufficient to sustain them. At the same time, expenditures on education, healthcare and infrastructures in these countries cannot grow at a rate comparable to that of the growth of the population: the low wages imply low tax revenues, resulting in insufficient public funds.
Both the above adverse economic phenomena are probably reversible. However, the birth rate would have to be reduced. Birth rate reduction means less overcrowded schools, fewer dependent and non-productive young people as well as fewer applicants per job. Such positive demographic change has already contributed to the economic ‘wonders’ in several East Asian countries. It is clear, however, that such breathtaking results cannot be guaranteed in all cases and will only appear in countries with good economic policy.
The migration of a large proportion of the rural populations to cities is another problem related to population growth. This trend tends to be economically positive in developed countries since the urban populations generally enjoy higher standards of living than the rural ones. The concentration of industries and the establishment of commercial and political centres are the main reasons for the rural population of developing countries moving from the impoverished countryside to the cities in great numbers. The overpopulated countryside, where it is a problem to sustain the ever growing numbers of people, seeks better income opportunities in the cities and thus security for large families. However, the migrant influx in economically weak countries is so great that it exceeds the supporting capacity of the cities, meaning that many of the immigrants end up destitute in suburban slums. The traditional urban advantages are suppressed in the poorest countries and the living conditions are often equally miserable or even worse than in the country.
The growing urban populations and expansion of built-up areas will probably be one of the main problems in the future. Less than 15% of the world’s population lived in towns (settlements of over 2,500 inhabitants) around the beginning of the 20th century. The urban population rates were up to 29% and 41% in 1950 and 1985, respectively. In 2008, for the first time, the majority of people are now living in cities. Around two-thirds of the world’s entire population will likely live in cities in 2020. It is already obvious that the fastest-growing cities are in the world’s poorest regions.
Population growth is not the only fundamental cause of the world’s social, economic and environmental problems, but it does make a substantial contribution. If the population had grown less rapidly in the past, we would be better-off now. And if population growth can be restricted in the future, the generations to come will be better-off.
Changing Consumption Patterns
The hypothetical gradual improvement in living standards in currently developing countries is another crucial problem for the coming years. It can be derived from the demographic transformation rules that reduced population growth comes hand in hand with the developing economies of countries in transition. What then does this transformation imply in environmental terms?
When industrialisation increases, the consumption of goods, raw materials and energies increases too: the so-called consumption patterns change altogether. Even very numerous populations in developing countries presently consume a fraction of the energies and raw materials and produce a fraction of the waste and greenhouse gases compared to industrialised economically advanced countries. The consumption patterns of the populations of those countries are very much different from economically developed countries both in quantitative and qualitative terms. Changing consumption patterns in those countries towards consumerism would mean drastically (however gradually) augmented demands on the environment, whether as a source of raw materials or an assimilation and detoxication mechanism for human emissions and waste. Any vision of an advanced industrialised world with a stable population will have to take this problem into account, like it or not. However, the primary problem of the future will be how and with what the increasing human population will feed itself.