Population Ecology G. Tyler Miller’s

Living in the Environment14th Edition

Chapter 9

Applying Population Ecology: Applying Population Ecology: The Human PopulationThe Human Population

G. Tyler Miller’sLiving in the Environment

14th Edition

Chapter 10

Population Ecology G. Tyler Miller’s

Living in the Environment14th Edition

Chapter 9

Applying Population Ecology: Applying Population Ecology: The Human PopulationThe Human Population

G. Tyler Miller’sLiving in the Environment

14th Edition

Chapter 10

Chapter 9 Key Concepts – Population EcologyChapter 9 Key Concepts – Population Ecology

Factors affecting population size Factors affecting population size

Species reproductive patterns Species reproductive patterns

Species survivorship patterns Species survivorship patterns

Conservation biology and human impacts on ecosystems

Conservation biology and human impacts on ecosystems

Population Dynamics and Carrying CapacityPopulation Dynamics and Carrying Capacity

Population dynamics Population dynamics

Biotic potential (intrinsic rate of increase [rmax]) Biotic potential (intrinsic rate of increase [rmax]) Environmental resistance Environmental resistance

Carrying capacity Carrying capacity

Exponential and Logistic Growth Exponential and Logistic Growth

Population Density Population Density

The Study of Population DynamicsThe Study of Population DynamicsPopulations change in Populations change in sizesize, , densitydensity, , dispersiondispersion and and age structure.age structure.

Population densityPopulation density —the number of individuals of a population that —the number of individuals of a population that inhabit a certain unit of land or waterinhabit a certain unit of land or water areaarea..

Population dispersionPopulation dispersion —refers to how individuals of a population are —refers to how individuals of a population are spaced within a region.spaced within a region.

Age structureAge structure of a population is usually described as the of a population is usually described as the pre-reproductive stage, the reproductive stage and the post-pre-reproductive stage, the reproductive stage and the post-reproductive stage. A population with a large reproductive stage is reproductive stage. A population with a large reproductive stage is likely to increase, while a populationlikely to increase, while a population with a large post-reproductive stage is likely to decrease.

Four variables influence/govern Four variables influence/govern population size: (1) population size: (1) birthsbirths, (2) , (2) deathsdeaths, , (3) (3) immigrationimmigration, and (4) , and (4) emigrationemigration..

Increase in population occurs by birth and Increase in population occurs by birth and immigration.immigration.

Decrease in population occurs by death Decrease in population occurs by death and emigration.and emigration.

Rapidly growing populations have four Rapidly growing populations have four characteristics:characteristics:

1.1. Individuals in the population reproduce early in Individuals in the population reproduce early in life.life.

2.2. Individuals have short periods between Individuals have short periods between generations.generations.

3.3. Individuals have long reproductive lives.Individuals have long reproductive lives.4.4. Individuals produce multiple offspring each time Individuals produce multiple offspring each time

they reproduce.they reproduce.

Population Size

The biotic potential max (rmax) is the population's capacity for growth. The intrinsic rate of increase (r) is the rate of population growth with unlimited resources.

limiting FactorsNo population can grow indefinitely due to limited resources such as light, water, and nutrients and also due to competitors and/or predators.

Biotic Potential vs. Biotic Potential vs. Environmental ResistanceEnvironmental Resistance

environmental resistance consists of factors that limit population growth.

Limiting Factors Examples:Limiting Factors Examples:

ExtrinsicExtrinsic

Biotic – Density Dependent

Abiotic – Density Independent

IntrinsicIntrinsicSocial HierarchyGender changing

Density-independent population Density-independent population controlscontrols affect a population's size affect a population's size regardless of its density. These are regardless of its density. These are abiotic factors in the community.abiotic factors in the community.

Density-dependent factors or Density-dependent factors or population controlspopulation controls have a greater have a greater affect on the population as its affect on the population as its density increases. Infectious density increases. Infectious disease is an example of density-disease is an example of density-dependent population control.dependent population control.

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Carrying capacity (K)

Environmentalresistance

Bioticpotential

Exponentialgrowth

Carrying capacity (K)Carrying capacity (K)is determined by biotic is determined by biotic potential and environmental potential and environmental resistance. resistance.

(K) is is the number of a (K) is is the number of a species individuals that can species individuals that can be sustained indefinitely in a be sustained indefinitely in a specific space.specific space.

As a population reaches itsAs a population reaches itscarrying capacity, itscarrying capacity, itsgrowth rate will decreasegrowth rate will decreasebecause resourcesbecause resourcesbecome more scarce.become more scarce.

Biotic Potential v. Environmental Resistance Biotic Potential v. Environmental Resistance (Logistic Population Growth)(Logistic Population Growth)

Natural Population CurvesNatural Population Curves

Fig. 9-7 p. 168

Population sizes may stay Population sizes may stay about the same, suddenly about the same, suddenly increase and then decrease, increase and then decrease, vary in regular cycles, or vary in regular cycles, or change erratically.change erratically.

Four general types of Four general types of population fluctuations in population fluctuations in nature are (1) nature are (1) stablestable, (2) , (2) irruptiveirruptive, (3) , (3) cycliccyclic, and (4), and (4) irregularirregular..

A A stablestable population fluctuates population fluctuates slightly above and below slightly above and below carrying capacity and is carrying capacity and is characteristic of many characteristic of many species Living under fairly species Living under fairly constant environmental constant environmental conditions.conditions.

Some species have a fairly stable population sizeSome species have a fairly stable population sizeThat may occasionally That may occasionally irruptirrupt to a high peak and then to a high peak and thencrash to below carrying capacity. This iscrash to below carrying capacity. This ischaracteristic of short-lived, rapidly reproducingcharacteristic of short-lived, rapidly reproducingspecies.species.

CyclicCyclic fluctuations occur over a regular time period, fluctuations occur over a regular time period,generally a multiple year cycle.generally a multiple year cycle.

IrregularIrregular behavior is poorly understood. Some behavior is poorly understood. Somescientists attribute irregular behavior to chaos in thescientists attribute irregular behavior to chaos in thesystem; others disagree.system; others disagree.

Exponential and Logistic GrowthExponential and Logistic Growth

The Role of Predation in Controlling Population SizeThe Role of Predation in Controlling Population Size

Fig. 9-8 p. 168

Interactions between Interactions between predators and their prey predators and their prey change in cycles and appear change in cycles and appear to be caused by species to be caused by species interactions, but other factors interactions, but other factors may be involved.may be involved.

The hypothesis of The hypothesis of top-down top-down controlcontrol of prey by predators of prey by predators may not be the only may not be the only explanation for the boom-and-explanation for the boom-and-bust cycles seen in these bust cycles seen in these populations. This may also be populations. This may also be related to the food supply of related to the food supply of prey.prey.

The The bottom-up controlbottom-up control hypothesis states that plants hypothesis states that plants are consumed too rapidly by are consumed too rapidly by prey for replacement to keep prey for replacement to keep up. This may lead to a crash of up. This may lead to a crash of herbivores, and that may lead herbivores, and that may lead to a crash of higher predators.to a crash of higher predators.

These are not mutually exclusive hypotheses; more probably have interaction between predation and food supplies.

Population dispersionPopulation dispersion Fig. 9-2 p. 164Fig. 9-2 p. 164

Most species live in clumps or groups; reasons may Most species live in clumps or groups; reasons may include: include:

Availability of resources varies from place to place.Availability of resources varies from place to place.

Living in groups offers better protection from Living in groups offers better protection from predators.predators.

Some predator species live in packs to better have a Some predator species live in packs to better have a chance to get a meal.chance to get a meal.

Temporary groups may form for mating and caring Temporary groups may form for mating and caring for young.for young.

Uniform pattern distribution may occur where a Uniform pattern distribution may occur where a resource, such as water, is scarce.resource, such as water, is scarce.

clumping dispersionclumping dispersion the the most common dispersion most common dispersion pattern for populations. In pattern for populations. In this type of dispersion, this type of dispersion, individuals "flock together.“individuals "flock together.“

uniform dispersionuniform dispersion a type of a type of population dispersion in population dispersion in which the members of the which the members of the population are uniformly population are uniformly spaced throughout their spaced throughout their geographic region. geographic region.

random dispersionrandom dispersion a type of a type of population dispersion in population dispersion in which the position of each which the position of each individual is not determined individual is not determined or influenced by the other or influenced by the other members of the population.members of the population.

Reproductive Patterns and Survival Reproductive Patterns and SurvivalSome species reproduce without having sex, and others reproduce by having

sex.

Asexual reproduction does not utilize sex; each cell can divide and produce two identical cells that are replicas of the original cell.

Sexual reproduction occurs when gametes from each parent combine toproduce offspring with a combination of genetic traits from each parent.

Three disadvantages to sexual reproduction:Males do not give birth; females have to produce twice the

offspring tomaintain the same number of young as an asexual organism.

Chance of genetic errors/defects increase during splitting and recombination.

Courtship/mating consume energy and time, transmit disease, and inflict injury on males in some cases

Two important advantages are genetic diversity for survival of species in the face of changes in environment and males may help with food gathering and/or rearing of young.

Reproductive Patterns and SurvivalReproductive Patterns and Survival

Fig. 9-10 p. 170

Reproductive patterns can be classified into Reproductive patterns can be classified into twotwo fundamental reproductive fundamental reproductive patterns: patterns: r-selected r-selected and and K-selected speciesK-selected species..

Availability of a suitable habitat for individuals of a population ultimately Availability of a suitable habitat for individuals of a population ultimately determines the population size.determines the population size.

Reproductive StrategiesReproductive Strategies

r-Selected species are opportunists and reproduce when conditions are favorable or when disturbance opens a niche for invasion. Most species of this type go through irregular and unstable boom-and-bust cycles in population size.

K-selected species generally follow a logistic growth curve. Many of the larger species with long generation times and a low reproductive rate are prone to extinction.

Survivorship CurvesSurvivorship Curves

Fig. 9-11 p. 171

Populations of different Populations of different species vary in how long species vary in how long individual members typically individual members typically live.live.

A survivorship curve is one A survivorship curve is one way to represent age way to represent age structure of a population.structure of a population.

Three generalized types of Three generalized types of survivorship curves are: survivorship curves are: late late lossloss, , early lossearly loss, and , and constant constant lossloss..

A life table shows the A life table shows the numbers of individuals at numbers of individuals at each age on a survivorship each age on a survivorship curve.curve.

Insurance companies use life Insurance companies use life tables to determine the cost tables to determine the cost of insurance policies.of insurance policies.

Effects of Genetic Variations on Population SizeEffects of Genetic Variations on Population Size

Variations in genetic diversity can affect the survival of small, isolatedVariations in genetic diversity can affect the survival of small, isolatedpopulations. Several factors can play a role in loss of genetic diversitypopulations. Several factors can play a role in loss of genetic diversityand survival of a small population.and survival of a small population.

The The founder effectfounder effect is when a few individuals move to a new location is when a few individuals move to a new locationthat is isolated from the original population. There is limited geneticthat is isolated from the original population. There is limited geneticdiversity in such a population.diversity in such a population.

A A demographic bottleneckdemographic bottleneck occurs when only a few individuals occurs when only a few individualssurvive a catastrophe.survive a catastrophe.

Genetic driftGenetic drift is a third factor and involves random changes in gene is a third factor and involves random changes in genefrequencies in a population. This may help or hurt the survival of thefrequencies in a population. This may help or hurt the survival of thepopulation.population.

InbreedingInbreeding occurs when members of a small population mate one occurs when members of a small population mate oneanother; this may increase the numbers of defective genes in a population.another; this may increase the numbers of defective genes in a population.

MetapopulationsMetapopulations occur where some mobile populations occasionally exchangeoccur where some mobile populations occasionally exchangegenes when some members get together. Conservation biologists use thisgenes when some members get together. Conservation biologists use thisinformation to establish migration routes that will enhance population size,information to establish migration routes that will enhance population size,genetic diversity, and survival of related local populations.genetic diversity, and survival of related local populations.

Human Impacts on EcosystemsHuman Impacts on Ecosystems

Habitat degradation and fragmentation Habitat degradation and fragmentation

Ecosystem simplification Ecosystem simplification

Genetic resistance Genetic resistance

Predator elimination Predator elimination

Introduction of non-native species Introduction of non-native species

Overharvesting renewable resources Overharvesting renewable resources

Interference with ecological systems Interference with ecological systems

Humans have altered Humans have altered nature in ways that nature in ways that threaten the survival threaten the survival of many species, of many species, including our own including our own species.species.

Humans have directly Humans have directly affected changes on affected changes on about 83% of the about 83% of the earth's land surface.earth's land surface.

Human Impacts on EcosystemsHuman Impacts on Ecosystems

Humans have altered nature to meet needs and wants in Humans have altered nature to meet needs and wants in ninenine major major ways.ways.

1. 1. Destruction, fragmentationDestruction, fragmentation, and degrading of wildlife habitats have reduced , and degrading of wildlife habitats have reduced biodiversity.biodiversity.

2. The 2. The simplification and homogenizationsimplification and homogenization of natural ecosystems by clearing of natural ecosystems by clearing land and planting land and planting a a single species (monoculture) reduces numbers of single species (monoculture) reduces numbers of species and interactions. Opportunistic species and pest organisms are species and interactions. Opportunistic species and pest organisms are costing time, energy, and money to control. Invasion of pathogenic costing time, energy, and money to control. Invasion of pathogenic organisms is another threat. organisms is another threat.

3. 3. Destruction of the earth's net primary productivityDestruction of the earth's net primary productivity is a third type of is a third type of alteration.alteration.

4. Certain types of 4. Certain types of intervention have unintentionally strengthened pest species intervention have unintentionally strengthened pest species and disease-causing bacteria.and disease-causing bacteria.

5. Some 5. Some predator speciespredator species have been deliberately eliminated from ranching have been deliberately eliminated from ranching areas.areas.

6. Alterations have occurred due to the introduction of 6. Alterations have occurred due to the introduction of nonnative (invasive)nonnative (invasive) or or new species into an ecosystem.new species into an ecosystem.

Human Impacts on EcosystemsHuman Impacts on Ecosystems7. A number of renewable resources have been 7. A number of renewable resources have been over-harvestedover-harvested, such as , such as

overgrazing of grasslands, over-hunting of wildlife, and pumping out overgrazing of grasslands, over-hunting of wildlife, and pumping out aquifers for freshwater faster than they can recharge.aquifers for freshwater faster than they can recharge.

8. Some human activities also 8. Some human activities also interfere with normal chemical cyclinginterfere with normal chemical cycling and and energy flows in ecosystemsenergy flows in ecosystems

9. Human-dominated ecosystems are increasingly dependent on nonrenewable 9. Human-dominated ecosystems are increasingly dependent on nonrenewable energy from fossil fuels that produce pollution and add energy from fossil fuels that produce pollution and add greenhouse gases greenhouse gases to the atmosphere. to the atmosphere.

Alteration of natural ecosystems needs to be slowed down, and we need to Alteration of natural ecosystems needs to be slowed down, and we need to maintain a balance between simplified, human-altered ecosystems and maintain a balance between simplified, human-altered ecosystems and more complex, natural ecosystems more complex, natural ecosystems

Learning from NatureLearning from Nature

Interdependence Interdependence

Unpredictability Unpredictability

Recycle wastes Recycle wastes

See Connections p. 173See Connections p. 173

Dependence on Nature Dependence on Nature

Limited resources Limited resources

Learning from NatureLearning from NatureBy mimicking four major waysthat nature has adapted andsustained itself, we can developmore sustainable economies.

We are totally dependent on thesun and Earth for life. We are anexpendable species.

Everything is interconnected andinterdependent. What connectionsare strongest, most important,and most vulnerable are thosethat we must discover.

Any intrusion into nature hasunexpected and unintended

sideeffects. We must not deplete anddegrade the earth's natural

capital.

Figure 9-15Figure 9-15Page 174Page 174Figure 9-15Figure 9-15Page 174Page 174

Principles of Sustainability

How Nature Works Lessons for Us

Runs on renewable solar energy.

Recycles nutrients and wastes. There is little waste in nature.

Uses biodiversity to maintain itself and adapt to new environmental conditions.

Controls a species population size and resource use by interactions with its environment and other species.

Rely mostly on renewable solar energy.

Prevent and reduce pollution and recycle and reuse resources.

Preserve biodiversity by protecting ecosystem services and preventing premature extinctionof species.

Reduce births and wasteful resource use to prevent environmental overload and depletion anddegradation of resources.

Solutions

Applying Population Ecology: The Human Population Chapter 10Applying Population Ecology: The Human Population Chapter 10

Key ConceptsKey Concepts

Factors affecting human population size Factors affecting human population size

Managing population growth Managing population growth

Human population problems Human population problems

Factors Affecting Human Population SizeFactors Affecting Human Population Size

Population change equationPopulation change equation

Crude birth rate (BR) The crude birth rate is the number of live births per 1,000 people in a population in a specific year.|

Crude birth rate (BR) The crude birth rate is the number of live births per 1,000 people in a population in a specific year.|

Crude death rate (DR) The crude death rate is the number of deaths per 1,000 people in a population in a specific year

Crude death rate (DR) The crude death rate is the number of deaths per 1,000 people in a population in a specific year

PopulationChange

PopulationChange == (Births + Immigration) – (Deaths + Emigration)(Births + Immigration) – (Deaths + Emigration)

Demography is the study of the size, composition, and distribution of human populations and the causes and consequences of changes in these characteristics.

Describing Population ChangesDescribing Population Changes

Doubling Times “Rule of 70”:Doubling Times “Rule of 70”: Doubling time is one measure of Doubling time is one measure of population growth. population growth.

FertilityFertility-is the number of births that occur to an individual woman in a -is the number of births that occur to an individual woman in a population.population.

Replacement-level FertilityReplacement-level Fertility —the number of children a couple must —the number of children a couple must have in order to replace themselves in a population.have in order to replace themselves in a population.

Total Fertility Rate (TFR)Total Fertility Rate (TFR) — —the number of children a woman will bear the number of children a woman will bear during her lifetime; this information is based on an analysis of data during her lifetime; this information is based on an analysis of data from preceding years in the population in question.from preceding years in the population in question.

Who is Over Populated?

Factors Affecting Human Population Size (2005 Data)Factors Affecting Human Population Size (2005 Data)There are currently more births than deaths throughout the world.There are currently more births than deaths throughout the world.

1. The annual rate of natural population change (%) equals birth rate 1. The annual rate of natural population change (%) equals birth rate minus death rate divided by 1,000 persons multiplied by 100.minus death rate divided by 1,000 persons multiplied by 100.

2.2. The rate of the world's population growth has decreased.The rate of the world's population growth has decreased.

3.3. The annual population growth dropped by almost half between 1963 The annual population growth dropped by almost half between 1963 and 2004, from 2.2% to 1.2%. But during this same period, the and 2004, from 2.2% to 1.2%. But during this same period, the population base doubled from 3.2 to 6.4 billion.population base doubled from 3.2 to 6.4 billion.

4.4. There is a big difference in the exponential population growth rates There is a big difference in the exponential population growth rates of developed and developing countries, with developed countries of developed and developing countries, with developed countries growing at 0.25% and developing countries growing at 1.46%— growing at 0.25% and developing countries growing at 1.46%— almost six times faster.almost six times faster.

5.5. The six fastest growing countries in terms of population are: India, The six fastest growing countries in terms of population are: India, China, Pakistan, Nigeria, Bangladesh, and Indonesia.China, Pakistan, Nigeria, Bangladesh, and Indonesia.

The populations of China and India comprise 38% of the world's The populations of China and India comprise 38% of the world's population. The next most populated country is the United Stated population. The next most populated country is the United Stated with 4.6% of the world's population.with 4.6% of the world's population.

Factors Affecting Birth Rates and Total Fertility RatesFactors Affecting Birth Rates and Total Fertility RatesMany factors influence birth and fertility rates.Many factors influence birth and fertility rates.

1.1. More children work in developing countries; they are important to the More children work in developing countries; they are important to the labor force.labor force.

2.2. The economic cost of raising and educating children determines their The economic cost of raising and educating children determines their numbers. The more children cost, the less children people tend to numbers. The more children cost, the less children people tend to have.have.

3.3. If there are available private/public pension systems, adults have If there are available private/public pension systems, adults have fewer children because they don't need children to take care of them fewer children because they don't need children to take care of them in old age.in old age.

4.4. People in urban areas usually have better access to family planning, People in urban areas usually have better access to family planning, so they have fewer children.so they have fewer children.

5.5. If women have educational If women have educational and economic choices, and economic choices, they tend to have fewer they tend to have fewer children.children.

6.6. When the infant mortality When the infant mortality rate is low, people have rate is low, people have fewer children because fewer children because children are not being lost children are not being lost to death.to death.

7.7. The older the age at which The older the age at which women marry, the fewer women marry, the fewer children they bear.children they bear.

8.8. If abortions are available If abortions are available and legal, women have and legal, women have fewer children.fewer children.

9.9. The availability of reliable The availability of reliable birth control allows women birth control allows women to space children and to space children and determine the number of determine the number of children they bear.children they bear.

U.S. Birth Rates: 1910-2004U.S. Birth Rates: 1910-2004Fig. 10-8, p. 180Fig. 10-8, p. 180

32

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1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Year

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Depression

End of World War II

Baby boom Baby bust Echo baby boom

From 1946-1964, the United States had a sharp rise in birth rate, called From 1946-1964, the United States had a sharp rise in birth rate, called the the baby-boom period. At its peak, the TFR reached 3.7 children per . At its peak, the TFR reached 3.7 children per woman. There has been a gradual decline since then. The population woman. There has been a gradual decline since then. The population growth of the United States is still greater than any other developed growth of the United States is still greater than any other developed country and is not close to leveling off.country and is not close to leveling off.

Factors Affecting Human Population SizeFactors Affecting Human Population SizeAbout 2.7 million people were About 2.7 million people were

added to the U.S. added to the U.S. population in 2004. Fifty-population in 2004. Fifty-five percent of this five percent of this population growth came population growth came from more births than from more births than deaths, and forty-five deaths, and forty-five percent came from percent came from immigration.immigration.

Other major developed Other major developed countries have slower countries have slower population growth, and population growth, and most are expected to most are expected to have declining have declining populations after 2010populations after 2010

The high U.S. per capita The high U.S. per capita resource rate use resource rate use produces enormous produces enormous environmental impact.environmental impact.

Immigration PolicyImmigration Policy

Arguments to limit immigration Arguments to limit immigration into the U.S.into the U.S.

• Limitations would aid in Limitations would aid in stabilizing the population stabilizing the population sooner.sooner.

• Limitations would help Limitations would help reduce the enormous reduce the enormous environmental impact of the environmental impact of the U.S.U.S.

Arguments for generous Arguments for generous immigration policies in the immigration policies in the U.S.U.S.

• Historically, the U.S. has been Historically, the U.S. has been the land of opportunity for the the land of opportunity for the world's poor.world's poor.

• Immigrants do work that Immigrants do work that Americans won't do or handle Americans won't do or handle jobs for which there are not jobs for which there are not enough trained natives.enough trained natives.

• Immigrants contribute to the Immigrants contribute to the economy and pay taxes.economy and pay taxes.

Factors Affecting Human Population SizeFactors Affecting Human Population Size

Factors, which have caused a decline in death rates, are the following:Factors, which have caused a decline in death rates, are the following:

1.1. Better food supplies and nutrition and safer water supplies Better food supplies and nutrition and safer water supplies contribute to people living longer.contribute to people living longer.

2.2. Advances in medicine and public health and improved sanitation Advances in medicine and public health and improved sanitation and personal hygiene also contribute to people living longer.and personal hygiene also contribute to people living longer.

Life expectancyLife expectancy is the average number of years a newborn can expect is the average number of years a newborn can expect to live.to live.

Infant mortality rate (IMR)Infant mortality rate (IMR) is the number of babies out of every 1,000 is the number of babies out of every 1,000 born who die before their first birthday.born who die before their first birthday.a. This rate reflects a country's level of nutrition and health care.a. This rate reflects a country's level of nutrition and health care.b. It is the single best measure of a society's quality of life.b. It is the single best measure of a society's quality of life.

U.S. infant mortality rate is higher than 35 other countries due to:U.S. infant mortality rate is higher than 35 other countries due to:a. inadequate health care for poor women and for their babies,a. inadequate health care for poor women and for their babies,b. drug addiction among pregnant women, andb. drug addiction among pregnant women, andc. a high birth rate among teenagers.c. a high birth rate among teenagers.

Ages 0-14Ages 0-14 Ages 15-44Ages 15-44 Ages 45-85+Ages 45-85+

Rapid GrowthGuatemala

NigeriaSaudi Arabia

Rapid GrowthGuatemala

NigeriaSaudi Arabia

Slow GrowthUnited States

AustraliaCanada

Slow GrowthUnited States

AustraliaCanada

MaleMale FemaleFemale

Zero GrowthSpainAustriaGreece

Zero GrowthSpainAustriaGreece

Negative GrowthGermanyBulgariaSweden

Negative GrowthGermanyBulgariaSweden

Fig. 10-14 p. 184Fig. 10-14 p. 184

Population Age Structure

Global Aging

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Stage 1Preindustrial

Stage 1Preindustrial

Stage 2Transindustrial

Stage 2Transindustrial

Stage 3IndustrialStage 3

IndustrialStage 4

PostindustrialStage 4

Postindustrial

Lowgrowth rate

Lowgrowth rate

Increasing Growthgrowth rate

Increasing Growthgrowth rate

Very highgrowth rateVery high

growth rateDecreasinggrowth rateDecreasinggrowth rate

Lowgrowth rate

Lowgrowth rate

Zerogrowth rate

Zerogrowth rate

Negativegrowth rate

Negativegrowth rate

Birth rate

Total population

Death rate

TimeTime

Fig. 10-20 p. 189

The Demographic Transition

Solutions: Influencing Population SizeSolutions: Influencing Population Size

MigrationMigration

Environmental refugeesEnvironmental refugees

Reducing birthsReducing births

Family planningFamily planning

Empowerment of womenEmpowerment of women

Economic rewards and penaltiesEconomic rewards and penalties

Case Study: Slowing Population Growth in IndiaCase Study: Slowing Population Growth in India

Generally disappointing results:

Poor planning

Bureaucratic inefficiency

Low status of women

Extreme poverty

Lack of support

Generally disappointing results:

Poor planning

Bureaucratic inefficiency

Low status of women

Extreme poverty

Lack of support

World in the Balance - India

Case Study: Slowing Population Growth in ChinaCase Study: Slowing Population Growth in China

Economic incentivesEconomic incentives

Free medical careFree medical care

Preferential treatmentPreferential treatment

Locally administeredLocally administered

Very intrusive and Very intrusive and coercivecoercive

Economic incentivesEconomic incentives

Free medical careFree medical care

Preferential treatmentPreferential treatment

Locally administeredLocally administered

Very intrusive and Very intrusive and coercivecoercive

World in the Balance - China

Population Growth in Sub-Saharan AfricaPopulation Growth in Sub-Saharan Africa

How do different populations compare?

Sub-Saharan Africa

Cutting Global Population GrowthCutting Global Population Growth

Family planning Family planning

Reduce poverty Reduce poverty

Elevate the status of women Elevate the status of women

Improve health care Improve health care

Increase education Increase education

Involve men in parenting Involve men in parenting

Sustainability Sustainability