Human Population

One of the great economic problems in the world is, there are unlimited needs, but limited resources. With populations growing exponentially each year, this problem of limited resources will become more and more significant. Since recorded time, some 2000 years ago, human populations grew quite slowly never exceeding 1 billion until around 1800. Today after only about 200 years the population has swelled to over 6 billion. How have populations swelled so fast over such a small period of time, and what effects will this have on future generations.

Early humans survived through hunting and gathering. They lived mostly nomadic lifestyles. With the Agricultural Revolution societies began to form and populations rose. However even with this new revolution populations were always kept in check through poor living standards, low food supplies, and more importantly diseases. By 1800, a new revolution was taking place. The Industrial Revolution brought about more efficiency, and people were able to use machines and factories to bring goods cheaply to many.

With the Industrial Revolution underway people already began to hypothesize the results of increasing populations. The economist Thomas Malthus provided an essay on the subject entitled, "Essay on the Principle of Population". Malthus explained that while human populations were growing exponentially, food supply was growing arithmetically. He predicted that widespread famine would eventually cause widespread deaths across the world. One thing Malthus had not accounted for was the Green Revolution.

The most important change for the world came about after World War 2 with what is called the Green Revolution. The Green Revolution revolutionized agriculture in developing countries. The Green Revolution was designed with intentions to eliminate famine, and bring modern farming techniques to developed countries. Around the same time new technologies in medicine were also reaching these areas. In the past, although birth rates in undeveloped countries were more then doubled then those in developed countries, populations were kept in check with high death rates. These new developments are the main reasons for the swelling populations in these areas.

Here we see data obtained from a project initiated by the UN to project expected populations through 2150. Separating underdeveloped countries and developed countries.

Figure 1

World Population Growth, 1750-2150

Source: United Nations, World Population Prospects, The 1998 Revision; and estimates by the Population Reference Bureau.

As can be seen from this data, the expected population of the world in 150 years will be over 10 billion people. Of these approximately 9 billion belonging to less developed countries.

Figure 2

World Population Distribution by Region, 1800-2050

From the above data we see that the world population existed mainly in Europe and Asia throughout history. While Asia's growth continues from this data we see that Europe's population is lowering dramatically when compared to the rest of the world. From 20.8% of the world in 1800 to only 12% in 2000. Looking at Africa we see they are on the way to becoming a much larger portion of the world in the next 50 years. There is already famine in this continent, and it is troubling to think what this population increase will bring.

Looking at data on the following page we can make some more interesting observations. Japan is actually seen as having a negative exponential growth over the next 25 years. This again proves that population rates in developed countries will shrink over time. Although US is a developed country it is still seen as having a significant population growth over the next 25 years. However most of this growth will be the result of assumed continual immigration policies of the US. While European countries and Japan are much stricter in this regard.

Figure 3

Projected Populations of Major Countries from 2004 to 2025

China I----------------------------------------------------------------I 2004

1.3 Billion

I----------------------------------------------------------------------I 2025

1.4 Billion

India I----------------------------------------------------------I 2004

1.1 Billion

I----------------------------------------------------------------------I 2025

1.4 Billion

USA I------------------I 2004

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