Major Factors Affecting the Increase in Population Growth

3752 Words Mar 24th, 2011 16 Pages
• Review of related Literature

As can be seen in Figure 1, the world's population grew very slowly until about 1750. There was a long period of stationary growth (no growth) until 1000 B.C.E., when the world's population was approximately 300 million; this was followed by a period of slow growth from 1000 B.C.E. to approximately 1750, at which time global population was an estimated 800 million. Until this time, the world's population was kept in check by high death rates, which were due to the combined effects of plagues, famines, unsanitary living conditions, and general poverty. After 1750, the world's population grew substantially; by 1950 it had tripled to around 2.5 billion. In this 200-year period, the doubling time was 122
…show more content…
As a result, the world witnessed unprecedented rapid population growth between 1950 and 1985, owing, in large part, to third world increases.

FIGURE 2
Further, the phenomenal increase in human numbers over the past 250 years is largely the consequence of mortality declines—not fertility increases. The first deaths to be reduced were those due to infectious diseases, the victims of which were most often children. The old killers of the past were to be replaced by chronic and degenerative diseases; the primary victims shifted from the young to the old.

The rate of global population growth has declined significantly from its 1970s highs (see Figure 2). Current estimates anticipate a continued decline to about 0.5 percent in 2050. This corresponds to a doubling time of 140 years, a rate that has fostered concern about how the world will cope with 18 billion people in 2190.
It is in the less developed countries that the continued growth in population will occur in the twenty-first century. Even though mortality is much higher in less developed countries (e.g., life expectancy at birth in 2000 was 75 years in the more developed countries and 62 to 64 years in the less developed countries), fertility remains even higher, thus accounting for relatively high growth in the third world. However, projections are not guarantees. Population may grow more slowly if, optimistically, fertility declines more quickly than experts