Demographers have revealed a remarkable correlation between the progress of industrialization and population growth. This has resulted in the theory of population cycle, a definite pattern of population progression that has been standard for industrial nations. The Demographic or population cycle can be reckoned from the standpoint of the Socio-economic history of a country. This criterion can be applied to gauge the demographic history of an advanced country.
The demographic cycle is applied to the whole world, various nations cut the cycle at different stages, mainly based on the population growth and industrialization of different countries. If the statistical data of the population growth of various countries is studied, the conclusion reached is that there are four stages of population growth termed as Demographic cycle. According to the growth of Demographic cycle the world population can be divided into the following sectors:
The First High Stationary Phase. The countries in this phase of development are marked by high birth and high death rates. In this category countries are included. Such as Tibet, Indonesia, Ethiopia, Iran, Arabia, Afghanistan etc. and countries of South America.
The major portion of the population resides in villages and their economic development and improvement of its living standards, thus depend largely upon the growth and progress of the agricultural sector of economy.
The Second Phase. The countries within this groups are Turkey, Burma, Sri Lanka, Pakistan, Madagascar, Egypt and Mexico etc. We have seen that the pressure of population is not evenly distributed. Large areas of land are lying devoid of human settlement, whereas some very small parts are thickly populated. This unequal distribution of human stock always seems the root of many political, economic and social problems. To some extent imperialism and colonism are the results of this uneven distribution of human stock over the globe. Every country is willing to establish the relationship between her increasing population and available natural resources. The economic systems of the countries in the second phase are characterized by improved agriculture methods, with the introduction of irrigation facilities and flood control measures. These countries are so densely populated that human efforts has been exploited to the maximum extent all the natural resources and has reached the optimum point of population and now they are entirely reached at melting point.
Before the present tremendous industrial development, the population of Japan increased very rapidly , that is not only doubled itself but also created an enormous number of surplus population for emigration to other countries. But now the conditions has become opposite especially in areas where industries and commerce have become the sources of livelihood rather than agriculture.
The Third Phase. The third phase of population cycle is more advanced and involves less wastage of human resources. In this phase come those countries where the birth and death rates are very low and the countries within this phase of population cycle are the United States, Norway, Great Britain, France, Denmark, Germany, Poland, Hungary, Belgium, Austria, Sweden etc.
In the above mentioned countries the birth and death rates are very low. In all European countries, the decline in birth rate received a slight check during the world war II. But there was a sharp rise in the number of children born after the second world war, the birth rate and death rate soon became stable, due to more deaths and fewer births. resulting in a small and steady growth of population.
Switzerland is a representative country that has a high standard of living with a population that is dense in relation to its cultivated area and with only waterpower and scenic beauty as natural resources.
The Fourth Phase of Population Cycle. The fourth and the final phase of the population cycle is characterized by an actual decline in the total population of a country by means of an excess of deaths over births. A perusal of the world's population indicates that such situations arise not so much of an excess of high death rates over the birth rates as through a considerably low birth rate. The effects of such trend in population growth are to be serious, when such as phase becomes permanent. The remedy lies in giving a stimulus to increasing birth rates and greater volume of immigration. Under such depopulation trends, the danger of a kind of race suicide is likely to come into force, but it does not imply the total disappearance of a human stock from certain parts of the earth.
Some of the developing nations of Asia and Latin America are on the path of economic development. Spread of education especially among women and external aid for economic development have resulted in decline in birth rate. These nations are likely to move to the third stage and achieve stable population in a few decades. Thus while some of the developing countries are likely to experience an increase in the death rate due to deteriorating environment conditions, other countries are likely to reach the level of developed nations by a gradual decline in birth rate.
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