Key Issue 4: Why Might the World Face an Overpopulation Problem?

Main Ideas:
Malthus on Overpopulation - English economist Thomas Malthus was one of the fist to argue that the world's rate of population increase was far outrunning the development of good supplies. Malthus claimed that the population was growing at a much faster rate that the food supply (exponential vs. linear). Malthus predicted the following relationships between people and food in the future:

• Today - 1 person, 1 unit of food
• 25 years from now - 2 persons, 2 units of food
• 50 years from now - 4 persons, 3 units of food
• 75 years from now - 8 persons, 4 units of food
• 100 years from now - 16 persons, 5 units of food

Malthus' supporters, or Neo-Malthusians, are contemporary geographers taking another look at Malthus' theory because of Earth's unprecedented rate of natural increase. They argue that the gap between population growth and resources in some places is wider than Malthus expected, as well as arguing that population growth means additional stripping of all resources, not just food resources.
Malthus' critics argue that Malthus was wrong because he viewed the world supply of resources as fixed and not expanding. A steady flow of new technology has off sett scarcity of minerals and arable land by using existing resources more efficiently and substituting mew resources for new ones. Modern scientists such as Ester Boserup and Simon Kuznets state that larger populations could in fact, stimulate economic growth. Population growth could generate more customers and more ideas for improving current technology.
Declining birth rates can be prescribed through NIR. NIR has showed that in the more developed countries, CBR has dropped from 15 to 10, while in lower developed countries, it has dropped form 31 to 24, and as a world collaboratively, 27 to 21. Two strategies have been successful in lowering birth rates: the use of contraceptives and the reliance on the economy. With more education, comes more awareness and better understanding if the potential hazards of have too many children. Women, for example, now have the knowledge to realize that have children too early, or having too many at that, will hinder their ability qualify for jobs in the workforce or complete the necessary requirements for education.


Sub Topics:
Epidemiologic transition is  distinctive causes of death in each stage of the demographic transition. Epidemiology is the branch of medical science that concerned with the incidence, distribution, and control of diseases that effect large numbers of people. A pandemic is a disease that occurs over a wide geographic area and affects a very high proportion of the population.


Some major diseases present that reflect the Epidemiologic transition model are:

• Black Plague- It is speculated that this originated from infected rats. Approximately 25 million Europeans died between 1347 and 1350. An additional 13 million deaths would be accounted for in China.
• Cholera - A pandemic disease, one in which occurs over a wide geographic area and affects a very high proportion of the population, became an especially virulent epidemic in urban areas during the industrial revolution. Nearly 1.5 million people died of this disease in New York City in the year 1832. 
• AIDS- the most lethal epidemic in recent years. There were 25 million people diagnosed with AIDS in in sub-Saharan Africa in 2006, 8 million in Asia, 2 million in North America/Western Europe, and 1 million elsewhere in the world.

The chart below displays the causes of death in the developed and still developing world in 1996. The leading causes of death, according to the chart, in the developing world are infectious or parasitic diseases, which are classified as stage 1 or 2 diseases. The leading cause of death in the developed world were diseases of the circulatory system, which are classified as stage 3 and 4 diseases.

Details:

The following video illustrates the need for contraceptives in less developed countries and the plans for implementing family planning.
Empty Handed: Responding to the Demand for Contraceptives

Key Issue 3: Why is Population Increasing at Different rates in Different Countries?

Main Ideas:The Demographic Transition - The demographic transition is the process of change in a society's population from a condition of high crude birth and death rates and low rate of increase to a condition of low crude birth and death ratse, low rate of natural increase, and a higher total population.
The Agricultural revolution was the time when human beings first domesticated plants and animals and no longer relied entirely on hunting and gathering. The industrial revolution was a series of improvements in industrial technology that transformed the process of manufacturing goods. The medical revolution was medical technology invented in Europe and North America that is diffused to poorer countries of Latin America, Asia, and Africa. Improved medical practices have eliminated many of the traditional causes of death in poorer countries and enabled more people to live longer and healthier lives. Zero Population Growth (ZPG) is a decline of the total fertility rate to the point where the natural increase rate equals zero.
Population Pyramids - Population pyramids are a means of displaying a country's population on a bar graph. A population pyramid normally shows the percentage of the total population in 5-year age groups, with the youngest group at the bottom and oldest at the top. The dependency ratio in a country is the number of people who are too young or old to work compared to the number of people in their productive years. The sex ratio is the number of males per hundred females in the population.

Sub-Topics:
There are four stages of demographic transition identifiable, each which can be associated with a corresponding population pyramid. These stages are:

• Stage One: Low Growth- crude birth and death rates varied considerably from one year to the next and from region to another, but over the long term they were roughly comparable, at very high levels. As a result, the NIR was basically non existent and Earth's population was virtually the same, at around half a million. During most of this period, people depended on hunting and gathering for food. When food was easily obtained, a region's population increased, but it declined when people were unable to locate enough animals or vegetation nearby. The escalated population growth around 8,000 B.C. was caused by agricultural revolution. By growing plants and raising animals, humans created larger and more stable sources of food, which transpired to more people surviving. Today, no county remains in this stage.

• Stage Two: High Growth- in this stage, the crude death rate suddenly plummets while the crude birth rate remains the same as it was in stage one. Because of the large disparity between the CDR and the CBR, the NIR in turn, becomes very high and population grows exponentially. Countries began the initiation of stage two after the conclusion of the Industrial Revolution. This revolution made huge improvements in industrial technology, with inventions such as the steam engine, mass production, and powered transportation. New machines helped farmers increase agricultural production and feed the rapidly growing population. The factories provided places of employment and enough food for industrial workers. The wealth that resulted from the Industrial Revolution was used to improve sanitation and personal hygiene. The improved standards of living allowed for people to be more healthy and therefore live longer. Countries in Europe and North America entered this stage in the 1800's, while most other countries in Africa, Asia, and Latin America didn't witness this movement until 1950. The medical revolution improved medical practices and suddenly put an end to many of the traditional and common causes of death in lower developed countries.

• Stage Three: Moderate Growth- When the CBR begins to drop drastically, a country moves into stage three. The CBR remains to drop, but at a much less rate than in stage two. However, the rate of natural increase is more modest in countries in stage three than in those in stage two because the gap between the CBR and CDR narrows. European and North American countries generally ,moved from stage two to stage three during the first half of the twentieth century, when most countries in Asia and Latin America have just made the transition in recent years. And still, most of African countries remain in stage two. Economic changes in stage three societies force people to produce fewer offspring. These people are more apt to live in cities as opposed to in the countryside, as they now work in offices, shops, or factories instead of being the pre-accustomed farmer. So essentially, having numerous children isn't a positive asset in the minds of parents. 

• Stage Four: Low Growth- A country reaches stage four of the demographic transition when the CBR declines to the point where it equals the CDR, and the NIR is approaching zero. This condition in known as zero population growth (ZPG). Increasingly, women in stage four societies enter the labor force rather than remaining a "stay-at-home" mother. Several Eastern European countries, most notably Russia, have negative NIR's, meaning that the number of deaths exceeds the number of births. Eastern Europe's relatively high death rates and low birth rates can be accredited to Communist rule. Higher death rates are a result of poor pollution control and low birth rates are a direct correlation to smarter family planning. (Low Growth from 1970's to today) 

Details: 

The article below describes the great change in sex ratio in Delhi, India from 2008 to now.

Delhi Sex Ratio Takes a Nose Dive

The video below consists of further explanation of population pyramids and their relation to development of a specified country.

Population Pyramids

Key Issue 2: Where has the World's Population Increased?

Main Ideas:
Natural Increase -Geographers most frequently measure population change in a country or the world as a whole, through the measures of:

• Crude Birth Rate (CBR)- the total number of live births in a year for every 1,000 people alive in the society. A CBR of 20 could be interpreted as for every 1,000 people in a country, 20 babies are born over a one year time span.
• Crude Death Rate (CDR)- the total number of deaths in a year for every 1,000 people alive in the society. Comparable to the CBR, the CDR is expressed as th annual number of deaths per 1,000 population.
• Natural Increase Rate (NIR)- the percentage by which a population grows in year. It is computed by subtracting CDR from CBR, after first converting the two measures from numbers to percentages. So, if the CBR is 20 and the CDR is 5, the NIR would by one and half percent.   

Approximately 80 million people are added to the world population each year. As the world continues to develop, nearly 100% of the world's natural increase rate comes from less developed countries who remain uneducated on methods of contraception and have few women in the workforce. 
Doubling time is the number of years needed to double the population, assuming a constant rate of natural increase. The graph below displays the global Natural Increase Rate in relation to the global crude birth rates and death rates.

Fertility -  Geographers also use the total fertility rate (TFR) to measure the number of births in a society. This is the average number of children a women will have throughout her childbearing years, which typically range from the ages of 15 to 49. The TFR for the world is 2.7. Less developed countries tend to have higher total fertility rates than more developed countries for the same reason that their natural increase rate is higher, women are not present in the workforce and are uneducated in methods of contraception.

Mortality - Mortality primarily refers to the crude death rate (CDR) or the number of deaths per 1,000 people in a country. Another principle of mortality is the infant mortality rate (IMR) which is the annual number of deaths  in infants under 1 year of age in comparison to total live births. 
The chart below displays countries in ascending order of infant mortality rates.

Details:

The following video explains causes of infant mortality rates and means of prevention, primarily in the United States, which actually has a higher infant mortality rate than the majority of other developed countries.
Reducing Infant Mortality


The article below expands on an unlikely life expectancy rate comparison to Spaniards and other citizens of European union countries.

Spaniards Live Longer Than EU Average, But with Worse Health

Key Issue 1: Where is the world's population distributed?

Main Ideas: 
Population Concentration - The population of the world, although spread out, is not distributed evenly. The majority of Earth's population can be found clustered in four regions. These regions are East Asia, Southeast Asia, South Asia, and Western Europe. These four regions possess similar characteristics that are cause for their magnitude of inhabitants. For example, all of these regions are located either near an ocean or near a river with easy access to an ocean, rather than being landlocked. All four regions are located in areas with low elevations that possess mild climates and fertile soil, and all regions are located in the Northern Hemisphere.
Sparsely Populated Regions - Certain regions of the world are undesirable for humans to occupy. The North and South poles of Earth are unoccupied due to the harsh weather and temperatures. However, areas that are extremely dry, wet, or mountainous to the point of hindering agriculture also tend to be uninhabited. Although the area of Earth possessing permanent human settlement is expanding, approximately 75% of the world's population lives on only 5% of the Earth's surface.
Population Density - Density can be described as the number of people occupying an area of land, and can be computed in several ways, including arithmetic density, physiological density, and agricultural density. Geographers use this density information to help determine the distribution of people in comparison to the resources available in a region.

Sub Topics:
Demography - The scientific study of population characteristics
Overpopulation - The number of people in an area exceeds the capacity of the environment to support life a a decent standard of living.
One method of displaying population distribution is through a population cartogram, which, as shown below, displays countries based on population size rather than by size of actual landmasses.

Ecumene - The portion of Earth's surface occupied by permanent human settlement.
The map below displays a 15th century map by Ptolemy of what was considered an ecumene at that time. Centuries of development and expansion have allowed the current ecumene to be nearly worldwide.

Arithmetic Density: The total number of people divided by the total land area.
Arithmetic density is the most commonly used principle because it's criterion are easy to acquire and results are easily comparable.
Physiological Density: The number of people per unit area of arable land.
This relationship informs geographers of the amount of pressure placed on the land in a region.
Agricultural Density: The ratio of the number of farmers to the total amount of land suitable for agriculture.
More developed countries tend to have lower Agricultural density because technology allows more work to be done by fewer laborers.




Details: 
The article below is a perspective result of today's world's overpopulation. It is possible that, even in developed countries such as the United States, overpopulation could cause a downfall of society.  
Overpopulation Basis of Problems 

The video link below is American philosopher Noam Chomsky's view on globalization and international sharing of intellectual and economic ideas.
Noam Chomsky on Globalization