Population pyramid - AbsoluteAstronomy.com

A population pyramid, also called an age structure diagram, is a graphical illustration that shows the distribution of various age groups in a population

Population

A population is all the organisms that both belong to the same group or species and live in the same geographical area. The area that is used to define a sexual population is such that inter-breeding is possible between any pair within the area and more probable than cross-breeding with individuals...

(typically that of a country or region of the world), which forms the shape of a pyramid

Pyramid

A pyramid is a structure whose outer surfaces are triangular and converge at a single point. The base of a pyramid can be trilateral, quadrilateral, or any polygon shape, meaning that a pyramid has at least three triangular surfaces...

when the population is growing. It is also used in Ecology to determine the overall age distribution of a population; an indication of the reproductive capabilities and likelihood of the continuation of a species.

It typically consists of two back-to-back bar graphs, with the population plotted on the X-axis and age on the Y-axis, one showing the number of males and one showing females in a particular population in five-year age groups (also called cohorts

Cohort (statistics)

In statistics and demography, a cohort is a group of subjects who have shared a particular time together during a particular time span . Cohorts may be tracked over extended periods in a cohort study. The cohort can be modified by censoring, i.e...

). Males are conventionally shown on the left and females on the right, and they may be measured by raw number or as a percentage of the total population.

Population pyramids are often viewed as the most effective way to graphically depict the age and sex distribution of a population, partly because of the very clear image these pyramids present.

A great deal of information about the population broken down by age and sex can be read from a population pyramid, and this can shed light on the extent of development

Sustainable development

Sustainable development is a pattern of resource use, that aims to meet human needs while preserving the environment so that these needs can be met not only in the present, but also for generations to come...

and other aspects of the population. A population pyramid also tells how many people of each age range live in the area. There tends to be more females than males in the older age groups, due to females' longer life expectancy.

A helpful analogy to facilitate understanding population pyramids is that just as a builder employs a blueprint for showing a house's structure, demographers and geographers employ population pyramids as a blueprint for showing population dynamics.

Types of population pyramid

While all countries' population pyramids differ, four general types have been identified by the fertility and mortality rates of a country.

Stable pyramid - A population pyramid showing an unchanging pattern of fertility and mortality.

Stationary pyramid - A population pyramid typical of countries with low fertility and low mortality, very similar to a constrictive pyramid.

Expansive pyramid - A population pyramid showing a broad base, indicating a high proportion of children, a rapid rate of population growth, and a low proportion of older people. This wide base indicates a large number of children. A steady upwards narrowing shows that more people die at each higher age band. This type of pyramid indicates a population in which there is a high birth rate

Birth rate

Crude birth rate is the nativity or childbirths per 1,000 people per year . Another word used interchangeably with "birth rate" is "natality". When the crude birth rate is subtracted from the crude death rate, it reveals the rate of natural increase...

, a high death rate and a short life expectancy

Life expectancy

Life expectancy is the expected number of years of life remaining at a given age. It is denoted by ex, which means the average number of subsequent years of life for someone now aged x, according to a particular mortality experience...

. This is the typical pattern for less economically developed countries, due to little access to and incentive to use birth control

Birth control

Birth control is an umbrella term for several techniques and methods used to prevent fertilization or to interrupt pregnancy at various stages. Birth control techniques and methods include contraception , contragestion and abortion...

, negative environmental factors (for example, lack of clean water) and poor access to health care.

Constrictive pyramid - A population pyramid showing lower numbers or percentages of younger people. The country will have a greying population which means that people are generally older, as the country has long life expectancy, a low death rate, but also a low birth rate. This pyramid has been occurring more frequently, especially when immigrants are factored out, and is often a typical pattern for a very developed country, a high over-all education and easy access and incentive to use birth control, good health care and few or no negative environmental factors.

Youth bulge

The expansive case was described as youth bulge by Gary Fuller (1995). Gunnar Heinsohn

Gunnar Heinsohn

Gunnar Heinsohn is a German sociologist and economist. He was born in Gdynia, Poland, under German occupation used as Kriegsmarine-Arsenal and named Gotenhafen, on November 21, 1943 to Roswitha Heinsohn, née Maurer and the late Kapitänleutnant Heinrich Heinsohn, last serving on U-438...

(2003) argues that an excess in especially young adult male population predictably leads to social unrest, war

War

War is a state of organized, armed, and often prolonged conflict carried on between states, nations, or other parties typified by extreme aggression, social disruption, and usually high mortality. War should be understood as an actual, intentional and widespread armed conflict between political...

and terrorism

Terrorism

Terrorism is the systematic use of terror, especially as a means of coercion. In the international community, however, terrorism has no universally agreed, legally binding, criminal law definition...

, as the "third and fourth sons" that find no prestigious positions in their existing societies rationalize their impetus to compete by religion or political ideology.

Heinsohn claims that most historical periods of social unrest lacking external triggers (such as rapid climatic changes or other catastrophic changes of the environment) and most genocide

Genocide

Genocide is defined as "the deliberate and systematic destruction, in whole or in part, of an ethnic, racial, religious, or national group", though what constitutes enough of a "part" to qualify as genocide has been subject to much debate by legal scholars...

s can be readily explained as a result of a built-up youth bulge, including European colonialism, 20th-century fascism

Fascism

Fascism is a radical authoritarian nationalist political ideology. Fascists seek to rejuvenate their nation based on commitment to the national community as an organic entity, in which individuals are bound together in national identity by suprapersonal connections of ancestry, culture, and blood...

, rise of Communism

Communism

Communism is a social, political and economic ideology that aims at the establishment of a classless, moneyless, revolutionary and stateless socialist society structured upon common ownership of the means of production...

during the Cold War

Cold War

The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...

, and ongoing conflicts such as that in Darfur

Darfur conflict

The Darfur Conflict was a guerrilla conflict or civil war centered on the Darfur region of Sudan. It began in February 2003 when the Sudan Liberation Movement/Army and Justice and Equality Movement groups in Darfur took up arms, accusing the Sudanese government of oppressing non-Arab Sudanese in...

and terrorism

Terrorism

Terrorism is the systematic use of terror, especially as a means of coercion. In the international community, however, terrorism has no universally agreed, legally binding, criminal law definition...

. Historical economic recessions, such as the Great Depression

Great Depression

The Great Depression was a severe worldwide economic depression in the decade preceding World War II. The timing of the Great Depression varied across nations, but in most countries it started in about 1929 and lasted until the late 1930s or early 1940s...

of the 1930s, are also claimed to be explained in part due to a large youth population who cannot find jobs.

One problem with this line of reasoning is that under conditions prevailing before the introduction of modern medicine, death rates were much higher than they are now, and almost all societies had youth bulges even when their population growth rate was negligible. However, they certainly did not experience such youth bulge as prevails today in some parts of the world or as prevailed in twentieth century Germany or in Africa and the Middle East nowadays.

It is not just that most periods of unrest occurred in societies with youth bulges, but that some of the pre-modern periods of any sort existed in societies with such bulges as well. Nevertheless, since the improvement of medicine and its introduction, the element of youth bulge has become far more salient than before. Therefore, perhaps it cannot explain massacres throughout human history, but it can serve as rather plausible theory to explain the terror, social unrest, and uprisings in today's society.

Another problem is that it ignores the social consequences of poverty, corruption and mass unemployment among young males in developing countries, where most of the world's current population growth is occurring. The "youth bulge" is not an accurate predictor of social unrest, war and terrorism, because they are the product of far more complicated and interrelated set of factors, of which demographics only plays a part. Yet, even when there are other factors and circumstance to enable mass unrest, a youth bulge is likely to be one of them.

Youth bulge theory represents one of the most recently developed theories of war

War

and social unrest, and has become highly influential on U.S. foreign policy as two major U.S. proponents of the theory, political scientists Jack Goldstone

Jack Goldstone

Jack A. Goldstone is an American sociologist and political scientist, specializing in studies of social movements, revolutions, and international politics. According to Peter Turchin , he made a significant contribution to the development of cliodynamics...

and Gary Fuller, have acted as consultants to the U.S. government.

The Middle East and North Africa

The Middle East

Middle East

The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...

and North Africa

North Africa

North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...

are currently experiencing a prominent youth bulge. Structural changes in service provision, especially health care, beginning in the 1960s created the conditions for a population explosion, which has resulted in a population consisting primarily of younger people. It is estimated that around 65% of the regional population is under the age of 30.

The Middle East has invested more in education, including religious education, than most other regions such that education is available to most young people. However, that education has not led to higher levels of employment, and youth unemployment is currently at 25%, the highest of any single region. Of this 25%, over half are first time entrants into the job market.

The youth bulge in the Middle East and North Africa has been favorably compared to that of East Asia, which harnessed this human capital and saw huge economic growth in recent decades. The youth bulge has been referred to by the Middle East Youth Initiative

Middle East Youth Initiative

The Middle East Youth Initiative is a program at the , housed in the program at the Brookings Institution. It was launched in July 2006 as a joint effort between the Wolfensohn Center and the Dubai School of Government....

as a demographic gift

Demographic gift

Demographic gift is a term in demographics used to describe the initially favorable effect of falling fertility rates on the age dependency ratio, the fraction of children and aged as compared to that of the working population.-Overview:...

, which, if engaged, could fuel regional economic growth and development.

Egypt's socio-economic challenges

The population of Egypt

Egypt

Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...

grew from 30,083,419 in 1966 to roughly 79,000,000 by 2008. The vast majority of Egyptians live in the limited spaces near the banks of the Nile

Nile

The Nile is a major north-flowing river in North Africa, generally regarded as the longest river in the world. It is long. It runs through the ten countries of Sudan, South Sudan, Burundi, Rwanda, Democratic Republic of the Congo, Tanzania, Kenya, Ethiopia, Uganda and Egypt.The Nile has two major...

River, in an area of about 40000 square kilometres (15,444.1 sq mi), where the only arable land

Arable land

In geography and agriculture, arable land is land that can be used for growing crops. It includes all land under temporary crops , temporary meadows for mowing or pasture, land under market and kitchen gardens and land temporarily fallow...

is found and competing with the need of human habitations. In late 2010, around 40 percent of Egypt's population of just under 80 million lived on the fiscal income equivalent of roughly US$2 per day with a large part of the population relying on subsidised goods.
According to the Peterson Institute for International Economics and other proponets of demographic structural approach (cliodynamics

Cliodynamics

thumb|Clio—detail from [[The Art of Painting|The Allegory of Painting]] by [[Johannes Vermeer]]Cliodynamics is a new multidisciplinary area of research focused at mathematical modeling of historical dynamics.-Origins:The term was originally coined by Peter...

), the basic problem Egypt has is unemployment driven by a demographic youth bulge: with the number of new people entering the job force at about 4% a year, unemployment in Egypt is almost 10 times as high for college graduates as it is for people who have gone through elementary school, particularly educated urban youth, who are precisely those people that were seen out in the streets during 2011 Egyptian revolution

2011 Egyptian revolution

The 2011 Egyptian revolution took place following a popular uprising that began on Tuesday, 25 January 2011 and is still continuing as of November 2011. The uprising was mainly a campaign of non-violent civil resistance, which featured a series of demonstrations, marches, acts of civil...

.

This is in stark contrast to others like Kuwait

Kuwait

The State of Kuwait is a sovereign Arab state situated in the north-east of the Arabian Peninsula in Western Asia. It is bordered by Saudi Arabia to the south at Khafji, and Iraq to the north at Basra. It lies on the north-western shore of the Persian Gulf. The name Kuwait is derived from the...

and Saudi Arabia

Saudi Arabia

The Kingdom of Saudi Arabia , commonly known in British English as Saudi Arabia and in Arabic as as-Sa‘ūdiyyah , is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula, and the second-largest in the Arab World...

, who are actively trying to engage and utilize their youth bulge, or Algeria

Algeria

Algeria , officially the People's Democratic Republic of Algeria , also formally referred to as the Democratic and Popular Republic of Algeria, is a country in the Maghreb region of Northwest Africa with Algiers as its capital.In terms of land area, it is the largest country in Africa and the Arab...

and Morocco

Morocco

Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...

, which have tried to mitigate the worst effects of a disenfanchised and disillusioned youth

Youth

Youth is the time of life between childhood and adulthood . Definitions of the specific age range that constitutes youth vary. An individual's actual maturity may not correspond to their chronological age, as immature individuals could exist at all ages.-Usage:Around the world, the terms "youth",...

Uses of population pyramids

Population pyramids can be used to find the number of economic dependents being supported in a particular population. Economic dependents are defined as those under 15 (children who are in full time education and therefore unable to work) and those over 65 (those who have the option of being retired). In some less developed countries children start work well before the age of 15, and in some developed countries it is common to not start work until 30 (like in the North European countries), and people may work beyond the age of 65, or retire early. Therefore, the definition provides an approximation. In many countries, the government plans the economy in such a way that the working population can support these dependents. This number can be further used to calculate the dependency ratio in that population.

Population pyramids can be used to observe the natural increase, birth, and death rate.

External links

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