The purpose of this chapter is to help you understand the dynamics, growth, and change of populations.
We'll show you some basic math tools to help you remember the statistics.
We will apply these concepts to the models of population geography after that.
We'll review several related concepts that show up frequently on the exam and finish with key terms.
The demographic equation and the rate of natural increase are used to understand population growth.
Population growth or change is shown by using birth rates and death rates along with immigration and emigration statistics.
In the next few pages, we will show you how population growth is calculated.
In this section, we're not going to give you a lot of math, but we will give you some helpful tips to understand how population changes occur.
The birth rate, also known as the crude birth rate or just the birth rate, is an annual stat.
The number of babies born in a year is calculated.
The population is divided by one thousand, or "every thousand members of the population," as it is often presented.
The quotient will be a small number, such as 32 or 14, if the denominator is standardized.
The data is easier to work with.
If you have a country with 100,000 live births in a year and a population of 5,000,000, the birth rate is 20; more precisely 20 live births for every 1,000 members of the population.
The simplified ratio is 5000 if you knock the three zeros off the end of 1,000 and the end of 5,000,000.
You have 20 if you knock off the three zeros.
There is more to the demographic picture than the birth rate.
When you look at the section on demographic transition later in the chapter, you'll find that high birth rates are found in rural Third-World countries and that low birth rates are more likely to be found in urbanized industrial and service-based economies.
It's hard to know if the population is growing or if the death rate is increasing.
It sounds frightening.
Death is an emotional issue.
You need to think about the statistics in a scientific way.
The death rate, also known as the crude death rate, is an annual stat calculated in the same way as the birth rate.
Every thousand people in a country are counted as deaths for the year.
War, disease, or famine can cause high death rates.
Poverty, poor nutrition, and a lack of medical care resulted in low life expectancy in Third-World countries.
Life expectancies have gone up and the death rate has gone down as a result of improved conditions in the Third World through the Green Revolution.
There is more on mortality in the section on stage one.
The rate of natural increase is calculated by comparing the birth rate and death rate for a country.
From here on, we'll call it the RNI.
The amount of population change per thousand members of the population is the difference between the death rate and birth rate.
If you divide the result by 10, you will get the RNI.
The annual percentage of population growth is called the RNI.
After you get the answer to the equation, make sure to put a % sign.
Let's use an example.
If a country has a birth rate of 27 and a death rate of 12 then the RNI is 1.5 percent.
If that country had 10,000,000 people the previous year, this year's population would be 10,000,000.
1.5 percent of the previous 10,000,000 people have been added.
The birth rate and death rate can be checked to see if they match the math.
In this country, the birth rate would be calculated as follows: 270,000 infants born divided by 27; the death rate would be 120,000 deaths divided by 12.
150,000 new people were added to the country's population.
It is possible to have a negative RNI.
The death rate can be larger than the birth rate, resulting in a negative number that is divided by 10 to get the negative RNI.
The population has shrunk when the RNI is negative.
In First-World countries that are highly urbanized and where the roles of women in the country have become such that the traditional positions of mother and homemaker have deteriorated significantly, a negative RNI can be seen.
The status of women in society has become more equal to that of men in these places.
When the majority of women are heavily engaged in business, political activity, and urban social networks, they are less likely to have children.
Another sign is higher divorce rates.
Germany is a prime example where the already low birth rates have dipped below death rates and as a result the RNI has ranged between -0.1 percent and -0.2 percent annually.
In this chapter, you can see examples of stage one and stage four of the Demographic Transition Model.
The rate of natural increase does not account for immigration or emigration.
If there is a large amount of emigration, a country with a high rate of natural increase can have a low long-term population prediction.
If the number of immigrants is high, a country with a low rate of natural increase can still grow.
Migrant populations have higher fertility rates than the general population.
In places such as the United States, population growth is not dependent on immigrants crossing the border, but on the fact that they will have large numbers of children once they have settled.
An RNI of 1.56 percent would result in a doubling time of 44.9 years.
We expect the 11 million people of today to grow to 22 million by 2063.
There is a negative net migration in the country.
The long-term prediction is 18 million by 2063.
The RNI is an estimate.
If you looked at a country's position on the Demographic Transition Model, you could estimate the RNI for each year in the future.
The method used to find the real dollar value over time is the same method used to estimate the value of a currency.
Population growth is calculated using the last part of the demographic equation.
We can add the balance to the net migration rate by using annual birth rates and death rates to calculate the natural increase in population.
The number of immigrants minus the number of emigrants is called the number of immigrants.
If you add this to the birth rate and the death rate, you will have total population growth per thousand members of the population.
The United States is an example.
The United States has a birth rate of 13 and a death rate of 8.
The United States adds about 7.5 people for every thousand in the population every year if we add the product to the net migration rate.
The population growth rate is 0.75 percent annually.
Net migration rates can be negative.
The population of Guyana is expected to fall over the long term due to net emigration.
The birth rate is 16 and the death rate is 7.
Adding to the net migration rate of -32, we find that the population growth is negative 23 per thousand.
The total fertility rate is the average number of children born to each female of birthing age.
The TFR isn't an annual stat like the RNI.
It is a snapshot of fertility for birth over the previous 30 years.
TFR and RNI are not the same.
Apples and oranges are not the same.
For one thing, you can't have a negative TFR.
Replacement is important in the population.
The replacement rate is 2.1.
In basic biological terms, think about this.
If there are two offspring, they have replaced themselves.
An error factor is what this is.
Some people will die before they reach adulthood because of diseases and accidents.
To replace itself, a large population must have 2.1 children per female of birthing age.
When a country hits a TFR of 2.1, population growth slows down as you hit the brakes on the car.
It's not until the RNI hits 0 that the population stops growing.
If the RNI goes negative, the car will roll backward and shrink the population as you try to find the emergency brake.
Knowing the number of people supported by a single individual in the labor force can be helpful.
The number of people too young or old to work is compared to the number of people in the work force.
There is less of a financial burden on those who work to provide financial support in a small population of dependents.
There are a number of uses for the Demographic Transition Model.
In your understanding of the AP Human Geography course, you should think of it as a central unifying concept.
It provides important insights into issues of migration, fertility, economic development, industrialization, urbanization, labor, politics, and the roles of women, as well as a theory of how population changes over time.
You are defining the population dynamics and economic context of a country by placing it on the model.
Knowing where a country falls on the model lets you know what kind of economy the country has, whether or not there is significant migration going on, and, like economic indicators, this "picture" of a country's population can tell you much about its quality of life.
Not all countries fit the model perfectly.
The lines are not always representative of every country's birth and death statistics.
The Epidemiological Transition Model is linked to the DTM due to the increasing population growth caused by medical advances.
As the procreation rates decline, the phase of development is followed by a stabilization of population growth.
There is a predictive capability in the Etm.
If a country falls within stage two of the transition, we can use this model to predict how the population will change over time and how much it will grow in size.
You can look at the whole world, which falls into early stage three.
We can estimate a population projection that the planet's population has only reached about two-thirds of its potential.
Once global populations level off in stage four, we can expect the global population to be around 10 billion people.
Sometime around 2060, this may happen in your lifetime.
Insight into economic history is provided by the DTM.
If we look at the United States, Canada, or Western Europe, we can see how the four countries have progressed through the system.
The Industrial Revolution, the beginning of the Renaissance, and the recent shift to service-based economies can be seen in the model below.
Human beginnings go all the way back.
There was a cultural and economic renaissance in Europe around 1400.
The United States and Great Britain were newly industrialized countries in the year 1800.
The rise of service-based economies of more developed countries happened in 2000.
A birth rate of 11 and a death rate of 10 is what the typical MDC has.
It is possible to place countries that are not demographically or economically advanced on the model, but you have to change the dates when they reach a turning point in their history.
We can see a turning point from the agricultural economy of stage two to the manufacturing-based economy of stage three in newly industrialized countries such as Brazil, Mexico, and India.
The model shows the NICs.
There are countries that are still agricultural based that can be outlined in the model.
On the next page, let's take a look at the two countries.
This is a theoretical model and not all countries fit it.
China appears to be more advanced than it should be due to its One- Child Policy.
Stage two agricultural economies have a lot of population growth to come.
Expect to see more rural-to-urban migration in these countries.
The population line in the model has a distinct shape until stage four.
demographers and biologists call it the S-curve.
Humans are not the only ones who follow this pattern.
Give any animal population a large amount of food or remove predators from their habitat and you will see rapid population growth followed by a decline due to a population reaching or exceeding the area's carrying capacity.
The human population may reach equilibrium in the global habitat if humans are doing the same thing.
In the Know the Concepts part of the chapter, we will talk about carrying capacity.
The best way to learn the model is not to memorize it, but to understand why the birth rate and death rate change over time.
The factors that affect population in each stage of the transition are examined in the next part.
Stage one was characterized by pre-agricultural societies engaged in seasonal migration for food and resources or owning livestock.
Climate, warfare, disease, and ecological factors are some of the factors that affect birth rates and death rates.
When death rates begin to decline, there is little population growth until the later part of stage one.
The RNI is usually low and can be negative during disease epidemics.
There are a number of reasons birth rates are high.
Children are an expression of a family's status.
Raising crops, hunting, gathering, herding, or laboring in the feudal political economy as domestic servants or soldiers could be done with the more kids a family had.
The high child mortality and infant mortality motivated parents to have a few extra children with the expectation that one or two would not live to adulthood.
Death rates are high for a number of reasons.
The overall population has a low life expectancy in stage one.
Long migrations and hard physical labor have the effect of wearing down the body and decreasing lifespan.
Death rates were high due to the combination of diseases like the plague and poor medical knowledge during the first stage of the DTM.
Third-world countries engaged in long periods of warfare have late stage one characteristics.
Third-World agricultural countries have stage two birth rates and death rates when they are peaceful.
The economic development of the region has been harmed by the AIDS epidemic in Southern African countries.
No countries meet the criteria for stage one based on 2016 demographic data if they have a death rate of more than 20.
Stage two countries are usually agricultural based.
Birth rates are high and death rates decline over time in this economic context, where agriculture for trade is the focus of the economy.
As birth rates and death rates differ, the rate of natural increase goes up.
When looking at the quality of life in Third-World countries, rapid population growth is a concern.
As the death rate goes down, life expectancy goes up, but still low compared to the First World.
Stage two countries with a more organized agricultural economy have high birth rates.
Compared to stage one, children are more important as a source of labor.
Poor nutrition and lack of medical care are some of the reasons why infant and child mortality is still an issue.
Most of the population in stage two countries live in rural areas because of agriculture's economic prominence.
Most cities in these countries don't reach their population growth potential.
There are a number of factors that affect death rates.
Populations engaged in the expanded agricultural economy tend to permanently settle in farming areas.
Improved farming methods and the domestication of draft animals reduce the incidence of death from excessive labor and travel by foot.
There is a larger and more varied food supply available to the general population as a result of the expanded trade in agricultural goods.
People live longer because of the increase in food volume, year-round availability, and quality.
Yemen is a good example of a stage two country.
It has a high birth rate of 28 and a low death rate of 6 over the past 50 years.
The life expectancy has increased to 66 due to the high rate of natural increase.
Nepal is an example from Asia.
The birth rate is 20 and the death rate 6 with an RNI of 1.4 percent annual population growth and a life expectancy of 71.
Agriculture is the main source of economic productivity in both countries.
This can be seen in the rates of urbanization.
64 percent of Yemen's population still lives in rural areas.
81 percent of Nepal's population lives in rural areas, which is starker than the rest of the country.
Population explosion is expected in these countries over the next few decades.
Yemen's population is expected to double in size to 60 million by the year 2050.
Nepal's population will grow from about 29 million today to around 36 million by the year 2050 due to high emigration.
The stages of the model are described by different terms in different human geography textbooks.
They're the same thing.
The NIC countries are characterized by economies that are transitioning their focus away from agriculture to manufacturing as the primary form of economic production and employment.
There are two different effects on the population.
There is rapid population growth in some countries.
The model shows that it's in the range between stages two and three where birth and death rates are closer together.
The model doesn't show the second effect, the rapidly increasing rate of urbanization.
More factories are being built in urban areas as these countries shift to manufacturing.
Migrants fill the cities with new and better-paying jobs because of the pull factor of employment opportunity.
The birth rates begin to decline.
As families move to cities, they find that they have less time, less need and less space for their children.
Children in cities are less likely to be seen as a source of labor because most countries forbid child labor.
Increased access to food markets, increased access to health care, reduced physical labor, and increased education have led to a decline in death rates.
Quality of life and access to services have led to a decline in death rates in Mexico.
Mexicans have a birth rate of 18 and a death rate of 5 with a resulting RNI of 1.5 percent.
The population adds over one million people per year.
Mexico is mostly urban, with 80 percent in cities, and the life expectancy has gone up to 76 years old.
Industrialization and urbanization have changed the population characteristics in Malaysia.
Malays have a birth rate of 19 and a death rate of 5.
The population is 73 percent urbanized.
Mexico appears to be ahead of Malaysia in terms of demographic development.
Mexico's population growth is expected to slow in the coming decades, while Malaysia's is expected to increase in population.
Mexico's population may fall by the middle of the 21st century.
Most "industrialized" or manufacturing-based countries were found in stage three.
Many former European Communist Second-World countries have shifted their economies to a more service-based focus.
The countries have completed the transition and are moving into stage four.
Many NICs will look like stage three as they continue to industrialize.
The effects of less space, time, and need factors along with increases in health care, education, and female employment have negative effects on fertility.
The availability of contraceptives in more urbanized and developed economies is influenced by access to health care.
Due to time constraints and the empowerment that women gain from their school and job experiences, fewer children are born due to women's education and employment.
Access to health care, nutrition, and education continue to increase life expectancy and decrease death rates in stage three.
Birth and death rates decline due to rapid medical advancement during this stage of the E.T.
The increasing affordability of health care is a hallmark of industrialized countries.
The death rates eventually bottom out.
We are all worm bait.
Everyone is going to die eventually and there is a statistical floor to the death rate.
You can't stop people from dying.
The life expectancies can go up even more in stage four.
China is more advanced demographically than its economic situation would predict.
China is more typical of a middle-to-late stage three country because of their One- Child Policy.
China has a birth rate of 12 and a death rate of 7.
The long-term effects of population control in China will continue to slow the growth of the country.
China will likely complete the S-curve in the coming decades.
The country is projected to reach over one billion by the year 2025.
China is only 56 percent urbanized because of Mao's " Back to the Land" policy, and things could change in terms of population projections if the One-Child Policy is completely lifted.
The late stage three characteristics of the country include a birth rate of 13 and a death rate of 9.
The country's life expectancy is 77, and it is extremely urbanized at 92 percent, as most of the country resides in and around the primate city of Montevideo.
The population of Uruguay is currently 3.3 million and is expected to increase to 3.7 million by the year 2050, an increase of 11 percent.
Birth and death rates converge in stage four to result in limited population growth.
We expect to find countries with service-based economies.
It's okay to think of them as "industrialized" countries, but keep in mind that these are service industries that drive the economy.
Manufacturing is dying in these countries.
In the United States, services make up 80 percent of the GDP and manufacturing makes up 20 percent.
The countries with the longest life expectancies are highly urbanized.
When birth rates bottom out into the teens, the final stages of the DTM and ETM occur.
There is a high degree of access to medical care, but the roles of women in society are such that most adult women are engaged in the labor force.
fecundity is reduced because of this result.
When birth rates reach the same level of death rates, you have a zero population growth and an RNI of 0.0 percent.
Birth rates can decline to a point where they are less than death rates.
There are four stages in the classical DTM.
Scientists didn't anticipate low death rates and low birth rates when they created this model nearly a century ago.
Adding a fifth stage to the DTM would reflect the potential for a negative RNI.
Japan and Germany are theoretically in or approaching this stage.
Japan is facing a potential population crisis due to a rapidly aging population and low fecundity.
Death rates are low and vary depending on age.
A younger average age will result in low death rates, while a higher average age will result in slightly higher death rates.
Western Europe and Anglo-North America have aging populations.
There tends to be a large population over the age of 65.
Canada has a birth rate of 10 and a death rate of 8.
The population should be around 42 million by the year 2050.
That doesn't seem right.
The rate of natural increase does not include migration into the country.
Canada, like the United States and the United Kingdom, has positive net migration, and many international migrants go to Canada.
Migrant populations have higher fertility rates than the general population.
Germany is an example of a Western European country that has experienced negative population growth in recent years.
Italy has a birth rate of 9 and a death rate of 10.
Due to labor immigration, Italy will have 63.5 million people by the year 2050.
The idea of a DTM stage five gets complicated here.
In theory, countries with a negative RNI should shrink their populations.
Many of these countries have positive net migration rates, so their populations remain steady or even grow slowly.
Some countries offer incentives to citizens to have more children.
With so few children being born, fewer people enter the workforce over time.
Many of these countries have become dependent on foreign guest workers, like the gastarbeiter in Germany, who have come from Turkey, North Africa, the Middle East, and the former Soviet Union.
Many former Communist countries of Eastern Europe have stage four demographic characteristics.
The factors behind this have recently come to light.
Many young workers in Eastern Europe and Russia have left for better paying jobs in the West.
In spite of their recent admission to the European Union, countries like Latvia,Lithuania, and Hungary have shrunk their populations.
The effects of Communism on the population in these countries have been pointed out by some.
Economic restructuring has brought hardship to many communities.
People were given incentives by the state to have children.
Many couples don't see any reason to have a larger family with government subsidies gone.
The point is to understand why the model works and not just memorize the lines on a graph.
An Essay on the Principle of Population was written by an Englishman.
His main idea was that the global population would grow to the point where it wouldn't be able to produce enough food to feed everyone.
The Malthusian catastrophe didn't happen by 1900 or even today, but some neo-Malthusians think it could happen in the future.
The United Kingdom was engaged in the Industrial Revolution and people were being born at a high rate.
Britain moved from stage two to stage three in the Demographic Transition Model.
Malthus saw rapid migration to the cities and a population explosion.
Malthus saw that food production grew in a slow way.
Each year another unit of food production was added to the total volume of agricultural products.
A couple has a few children and then their children all have a few children, and so on through generations.
A J-curve of exponential population growth can be seen on the graph when you have population + the population 2.
Malthus thought the population was going to catch up fast.
Malthus could not have predicted that agricultural technology would increase food production several times over in the next century.
The internal combustion engine, artificial fertilization, pesticides, irrigation pumps, advanced plant and animal hybridization techniques, the tin can, and refrigeration were all developed by 1900.
Another large volume of food would be added to global production and supply as each of these new products and methods was adopted.
Food production has remained ahead of population growth.
When the world's population is predicted to hit 10 billion by the year 2050, we should hope that the world's food production is in good order.
The first research on genes and plant reproduction took place in the early 1800s.
Genetics did not have an impact on global food production until the 1950s and genetically modified foods did not enter markets until the 1980s.
If you are asked about why Malthus was wrong, talk about new technologies like plant and animal hybrid, but not genetics, since that has affected agriculture only in recent years.
Some theorists warn that a Malthusian catastrophe could still happen.
You might think that things are okay now, and that within a generation or two, the global population will level off.
There may be problems keeping up with food demand when the world reaches 10 billion people.
Significant ecological problems like soil erosion and soil nutrient loss are already present in many major agricultural regions.
Per Capita demand is increasing.
The amount of food consumed is increasing.
A person in the Third World consumes less food and resources than a person in the First World.
Consumers in the Third World will increase their demand for food and other products over time.
The concern of neo-Malthusians is more than food.
Paul Ehrlich warned about the over-consumption of other resources.
We need to conserve and look for alternatives until we have Star Trek-esque replicators to make food for us and fusion reactor to make energy.
It sounds like a game show.
Population pyramids are a way to see the population structure of a country.
Population pyramids show the gender and age distribution of the population.
The shape of the pyramid can tell you a lot about a country's level of economic development.
The pyramid has males on the left and females on the right.
Each bar has an age cohort made up of five-year sets.
As you move left or right from the center, the origin of the bar graph increases in value.
There is only one gender in the age-sex cohort, with the single colored bar right or left of the origin.
There are gaps where there is a small bar.
A gap in males and females of the same age group is a sign of a war that was fought outside the country.
A gap in data for both males and females is a sign of war, epidemic disease, or famine in that country.
The sex ratio tells you the number of males and females in a group.
Some pyramids look different.
There could be a column down the middle, depending on who drew them.
The shape of the pyramid is important.
You will be used to seeing it both ways if we use both methods here.
They don't know what they are going to put on the exam.
The bars on the graph can show the percent of the total population or the number of people in the age-sex cohort.
You should know how to read and interpret the population pyramid graph that you will see on the AP exam.
We need to be sure that we're referring to the data that we're talking about when we say "percent versus total" in the essay section.
The shape of the pyramid tells you about the character of the country, state, province, or city.
Pyramid shapes are indicators of growth rates and economic development in countries.
Take a look at this example.
The war only affected one group of people and only men.
There would be a decline in the women if the war happened in this country.
The baby bust followed a baby boom.
After the war generation exceeds child-bearing age, booming fertility will stop.
Significant declines in the elder population can be caused by disease and old age.
That's why the top shrinks quickly.
The male side of the pyramid decreases in number more quickly than the female side.
Women live up to 5 years longer than men.
For different scales of population, you can have population pyramids.
States and cities may also show up on the exam.
The peak for the 50 to 54 cohort was noted.
Both male and female lived in Germany during World War II.
Many of the war's final years were fought in Germany.
The baby boom in Germany lasted longer than it did in the US.
The food rationing that took place after the war is likely to be the reason for the late peak.
Rhode Island is the slowest-growing state in the country.
There are 1.5 children per female below the replacement rate.
The child-age population is declining.
Rhode Island's population structure could look a lot like Germany or Italy within a decade.
Utah is one of the fastest-growing states due to immigration and a high fertility rate.
The boom and bust cycles are different here than in Rhode Island.
There are some interesting patterns in the cities.
Sun City, Arizona is a suburb of Phoenix that has long been a retirement destination for older Americans.
There are almost no children.
Morgantown is a university town.
The city's structure is cross-shaped because of the large college-age cohort.
There is an age structure similar to that of Mexico just across the Rio Grande.
Population growth can be affected by immigrant communities in border towns.
There are two ways to calculate population density.
The number of people per square unit of land is known as arithmetic density.
Most island nations and microstates have very high densities.
Consider the high densities of countries such as India, Bangladesh, Japan, and South Korea.
The number of people per square unit of land is known as the physiologic density.
It is possible to understand the sustainable nature of a population of a certain region or country by using cardiopulmonary density.
It is important to understand the geography of countries where the amount of arable land is limited.
There are limits to physiologic density due to geography.
Iraq, Egypt, Uzbekistan, and Pakistan are all arid countries with narrow farming regions around river systems.
In countries like the United States and China, arable land is located in the eastern third of the country, while the west is dominated by mountain and desert regions.
Populations have been squeezed into cities or into grassland and arid regions because of high densities in farming regions.
The population center can be found by averaging the weight of the population across the country.
The geographic center of the country is simply the geometric center of the country.
Imagine the country as a flat surface with the population standing on top in their home locations.
The population center is where you could balance the weighted surface without tipping it over.
Since the first census in 1790, the population center has moved to the west.
The land in the Eastern United States was already owned.
Immigrants arriving in the country and those wanting to have their own farms found no land available east of the Appalachian Mountains.
Most migrated west to start their own farms in the Midwest and Great Plains regions.
The population center moved west during World War II.
The population moved south and west after World War II.
There is more on the Frostbelt to Sunbelt shift.
From 1950 onward, the southwestern shift moved toward the Sunbelt.
Carrying capacity is the most important concept to understand about the global population.
At the regional level, we can look at thesustainability of certain population densities.
There are limits to how many people an environment can support in terms of the availability of food, water, and natural resources.
Some regions are more supportive of human settlement than others.
The deserts support less people than the temperate grasslands.
In resource-poor regions and across the globe, overpopulation is a major concern.
There are warnings regarding excessive consumption of natural resources.
The message is that if government mandated population control methods are not used, certain resources like clean water, and nonrenewable energy sources like oil will be rendered useless.
There is a need for zero population growth to stem the tide of resource depletion.
Large-scale family-planning and contraceptive programs have been proposed.
Many have rejected these ideas because of their religious or political beliefs.
As population densities increase, concerns over decreasing amounts of personal space would be alleviated.
Some worry that too many people crammed into densely packed urban areas will lead to social unrest and armed conflicts.
Population theorists have looked at the role of conservativism.
With an expected 10 billion person global population, massive and systematic global programs are believed to be necessary to achieve sustainable resource use.
Many resources could be lost before we have the chance to save them.
There are several different forms of migration.
Interregional migrants move from one region to another.
Rural-to-urban migrants move from farmland to cities in the same country.
There are migrants who move from one area to another within the same region.
There are variations in international migration.
Migrants move from one country to another.
Migrants can be slave, job-seeker, or refugee.
Humans move for many reasons and there are many theories about why.
The human capital theory of migration claims that humans take their education, job skills, training, and language skills to a country where they can make more money and reap a higher net return.
The net gain from migration is increased by higher levels of human capital.
The flow of human capital from one country to another causes wages to fall in the destination country while increasing in the sending country.
When the expected net earnings and costs of migration are the same, migration stops.
People who move from location to location are called migrants.
There are different forms of forced migration.
Governments can order their citizens to leave.
Other people forced to flee because of war, disasters, or fear of the government are known as refugees.
Some countries have official programs to receive refugees from other countries and grant them asylum, either temporarily or permanently.
Many countries in the 1990s had asylum programs for people who fled ethnic cleansing in the former Yugoslavia.
The host country faces enormous economic burdens when it comes to providing a new home for refugees.
If a developing nation is struggling to provide for its own people, basic food, water, sanitation, and safety needs are often barely met in the host country.
In most countries, people who come seeking refuge or employment opportunities but do not have government authorization are considered illegal immigrants.
Illegal immigrants in some countries can apply for official status or citizenship without being arrested or deported.
There are specific ways that people migrate.
When people move up in a hierarchy of locations, each move to a more prosperous place.
A family might move from a farm to a neighboring town, then from a regional city to the outskirts of a larger metropolitan area, and finally from there closer to the center of the city, each time taking advantage of better work opportunities.
They might move closer to the center of the city once economic stability is achieved and they want to have full access to the central business district.
Along the way, there will be opportunities for work and economic improvement.
Chain migration occurs when a group establishes a foothold in a new place.
Information is sent back to friends, family, and business contacts by these people.
Information on employment opportunities, access to markets and social networks, and encourage others to migrate to the location are provided by the pioneer.
A growing immigrant community is established as more and more people move in.
Some people who migrate for employment have a pattern of movement.
Foreign employees working for a limited period of time before returning to their home countries are called transnational labor migrants.
Sometimes this is also called periodic movement if it is on an annual or seasonal basis, for example, agricultural workers coming from Mexico to the United States for different harvest periods and then returning home to help out during harvest on their family farms.
Cyclic movement can last several years for an individual.
Sometimes foreign workers come to a country to find a job and then return to their home countries when they reach old age.
The countries that receive cheap labor benefit.
The cost of receiving immigrants includes crime, unemployment, social welfare, and national security concerns.
Losing highly skilled workers is a big challenge for countries that lose them.
Sending of money to family and friends is the largest positive economic effect of migration.
Money and other cash transfers are sent from migrants to their families back home.
Remittances are more likely to flow back home than official development assistance.
Remittances have a positive impact on the migrant's home country.
In rural Mexico, hundreds of communities are supported by the money they receive from labor migrants in the United States.
Someone doesn't have to cross international borders to be considered a migrant.
Internal migrations can change the country's population distribution.
Over the past few decades, there has been a migration of people from the Frostbelt to the Sunbelt in the United States.
Many people left the Northeastern United States for better employment opportunities in the South and Southwest because of the decline in manufacturing employment there.
Over the past 50 to 60 years, the average center of the U.S. population has moved to the south and west.
Atlanta, Dallas, Houston, San Antonio, Albuquerque, Phoenix, San Diego, Los Angeles, and Las Vegas are some of the large Sunbelt cities.
Denver, San Francisco, Salt Lake City, Portland, and Seattle can be included.
The Historic Population Centers map shows how this has affected population distribution.
Major changes in the course of a person's life are referred to as life-course changes.
Going to college, moving for a better job, or retiring are some of the life-course changes that explain internal migration within a country.
There are many ways in which life-course changes can occur.
Older people move when they stop working.
In the five-year period 1995-2000, almost 10% of Americans ages 60 and older migrated between counties.
Senior citizens are less likely to pick up and move than young people.
Young people begin a series of migrations when they leave home for college because of life-course changes as much as the amenities of place and quality of life.
Newly industrialized countries experience rapid internal rural-to-urban migration.
Employment at urban manufacturing locations is the main opportunity for internal immigrants.
A number of push and pull factors can cause people to leave a rural lifestyle and move to a city.
Push factors are things that make people leave the farm.
Pull factors are things that draw people to the city.
The opposite of a pull factor is not a push factor.
The lack of employment opportunities in rural regions is not a pull factor.
The AP Exam asks multiple-choice and free-response questions about push and pull factors.
Issues related to the hardship faced in rural areas are included in push factors.
An armed conflict is a push factor.
Rural regions are where rebel movements start military campaigns against governments.
Conflicts in rural regions can cause people to flee to the safety of cities.
Drug traffickers and terrorism can frighten people off the land.
Another factor is environmental pollution.
Chemicals used in agriculture can poison soils and water supplies.
In addition, improper usage of pesticides could lead to birth defects in children, forcing parents to move to cities to seek constant medical care for their children.
Push factors include natural disasters.
A flood can destroy a whole year's income and cause people to leave farming as their primary source of income.
Land costs can cause people to leave the land.
Markets for land in newly industrialized countries inflate prices.
Farmers who own land may be able to sell their land and make more money than they could in several years of farming.
New city housing can be paid for with this money.
Rents can increase significantly when farmers are renting land.
Farmers can no longer afford to pay rent or make enough money to support their families.
Migrants who arrive in cities homeless are often forced into settlements.
Even though land and other commodity prices may increase over time, basic food crop prices tend to change very little over the long term, making farming less profitable for small family farms.
Employment-related pull factors draw people to cities.
The number of job opportunities, pay rates, and regularity of pay are some of the factors that can motivate migrants to move to the city.
Farmers only make money at the end of the growing season when crops are sold.
Migrants have better financial security if they have regular paychecks.
Other factors that pull workers into the city include access to services such as medical care or education.
Migrants cite entertainment as a reason to move from rural areas.
Television, movies, festivals, and sporting events are popular in urban areas.
Chapter 9 contains information on where and how people in Latin America live.
The water quality in rural regions may be better than the water quality in cities, which is an unfortunate reality for many Third-World rural-to-urban migrants.
Water systems in the Third World are often contaminated.
If you are asked about access to service in Third-World cities, clean water is not a valid answer.
The demographic equation, the rate of natural increase, and doubling time are some of the statistics used to analyze population growth.
The classical model has four stages, but modern social scientists would like to add a fifth stage to reflect the negative RNI of some developed countries.
The global population would expand beyond its capacity to produce enough food to support itself before 1900, according to the Malthusian theory.
We've avoided this catastrophe so far thanks to technological innovation in agriculture, but neo-Malthusian theorists think it could still happen.
Population pyramids show the age and gender distribution of the population.
The shape of a pyramid can show a lot about growth rates and economic development.
Population density can be calculated.
Without a Malthusian collapse, the population that an environment can sustain is called carrying capacity.
In areas with poor natural resources and exploding populations, there are major concerns.
Interregional, rural-to-urban, and transnational are some of the scales where migration can take place.
Education or better economic opportunities are some of the reasons why most migration is voluntary.
Some migrants are forced to leave due to war, natural disasters, or fear of persecution.
Those who have been displaced are considered refugees.
Push factors can force migrants to leave their homes.
Poor economic conditions, armed conflict, environmental hazard, or increased land costs can be included.
Pull factors are positive attributes that draw migrants to a location.
Access to services and entertainment can attract migrants to urban areas, but the most significant of these is better employment and economic conditions.
There are answers and explanations at the end of this chapter.
The optimal TFR for a society is 2.1.
Many Western European countries have TFRs between 1.4 and 1.8.
The choice is correct.
In the first stage of the Demographic Transition Model, societies engage in farming and transhumance for food and resources.
Birth and death rates are high in the first stage so all of them can be eliminated.
Full industrialization does not occur until stage three, so choice can be eliminated.
Zero population growth occurs when a country's birth rate is the same as its death rate.
The correct answer is (C).
When an economy becomes more urbanized, the economy becomes more developed, and access to health care increases, contraceptives become available.
The characteristics of a society are in the third stage of the Demographic Transition Model.
A society's population is growing quickly.
A negative RNI means that the population is decreasing.
The reason that urban families are smaller than agricultural families is due to the fact that more people are living in cities.
Women turning away from the traditional role of mother, and the traditional role of wife, are some of the signs that birth rates are decreasing.
Double-income-no- kids is not contributing to a birth rate.
Increased immigration would result in a positive RNI.
Stage 1 societies are pre-agricultural according to the Demographic Transition Model.
The hallmark of stage two is the shift to an agricultural society.
A hallmark of stage two society is the divergence of birth rates and death rates--usually the birth rate remains high while the death rate decreases due to better nutrition and health care.
At some point in the future, the increase in human population would surpass the increase in food production according to the Malthusian prediction.
Massive hunger and population decline would result from this.
He could not have foreseen the growth of revolutionary advances in agriculture because his calculations were correct.
There is a push factor that forces people off the farm.
A pull factor is a specific thing about an urban environment that draws people to it.
The only pull factor is the better opportunity for employment in urban areas.
A population pyramid shows the gender and age distribution of the population.
The genders are equal in each country.
There is no indication of either a baby bust or external war.
Economic growth can be gauged from a population pyramid, but the safer bet is the rate of growth.
The population shaped like a triangle will experience a higher rate of growth than the population shaped like a rectangle.
The countries with the lowest total fertility rate have been the most welcoming to immigrants.
The population of those countries has remained high because of the foreign population.
It has led to a backlash against Muslim immigrants.
The financial burden on those who work is low in a population with a low dependency ratio.
There is a heavy financial burden on those who work in a population with a high dependency ratio.
In the United States, the dependency ratio has been increasing for many years due to the fact that the percentage of the population under the age of 30 has increased.
Canada and other nations have different points for both measures.
The mean center is the centroid, whereas the median center is the intersection of the median latitude and longitude.