Chapter 9The Human PopulationMr. ManskopfNotes also at http://www.manskopf.com

Chapter 9 Big IdeaThe size and growth rate of human population has changed drastically over the last 200 years. Those changes have led to profound changes to almost every place on Earth.

Section 1: Studying Human PopulationsDescribe how the size and growth rate for human population has changed over historyWhat factors lead to population changesAnalyze populations using Age Structure DiagramsTerms: Demography, Age Structure, Survivorship, Fertility, Migration, Life Expectancy

Describe what you see on this graphHow long did it take to get to 1 billion, than 2, 3,4,5,6How many people are living today?

Why do you think it took off around the late 1880s?

Studying Human PopulationsDemography: the study of human populationHow many people live where?How long are you expected to live?How many children are you likely to have.

Exponential GrowthExponential Growth: rapid growth often seen as J-Shaped curve on a graphCan that growth continue?

Forecasting Population SizeWill new schools be needed?Should we be building more housing?Should farming practices be improved?Predictions like this often wrong because human behavior changes

Forecasting Population SizeAge Structure: the distribution of ages in a populationAge Structure Diagrams aka population pyramidsWhat is useful about these diagrams?

What are these age-structure diagrams showing?What are the reproductive years Why is that important in forecasting future population growth?

Which type of countries are going to see most of the population growth?Which type of countries do people live longer lives? Survivorship: percent of population likely to survive a given age

What causes population to rise?Population Changes =(births + immigration) (deaths + emigration) For world population growth we are only concerned about births and deaths.

Fertility RatesFertility Rates: number of babies born each year per 1,000 womenTotal fertility rateReplacement rate fertility

Fertility and WomenTwo main factors impact fertility rates worldwideEducation level of women (knowledge of family planning)Economic level of womenGenerally, on average, more education, more wealth = lower fertility rates

What does this graph show?How has U.S. fertility rates changed?

Migration: movement INTO (immigration) or OUT of (emigration) an areaPopulation Change = (births + immigration) (deaths + emigration) U.S. growth continues because of both births and immigration

Death rates on the decline people living longerWhy?

Population Change = (births + immigration) (deaths + emigration) Better hygiene, sewage disposal, clean water, medicines, education, access to food, nutrition

Life ExpectancyLife Expectancy: average number of years members of a population are expected to liveImprovement in most of worldLower INFANT MORTALITY

Compared to our neighbors

Major changes in U.S. over last 100+ years

Demographic TransitionEvery Country Goes Through ItExplain what you see on this chart

Stage 1 : High Birth AND Death rates = little population change Stage 2 : Death Rates Fall, Birth Rates Still High = Population Growth Stage 3: Death Rates Low, Birth Rates Drop = Population Growth Slows Stage 4: Death Rates Low, Birth Rate Low = Population DeclinesDESCRIBE EACH STAGE: WHAT DO YOU SEE?

CalculationsA town currently has a population of 20 people. If 10 people are born, 8 people die, 3 immigrate and 1 emigrate, what is the population?

CalculationsUSA currently has a population of 320,000,000 people. If 5,000,000 people are born, 2,000,000 people die, 200,000 immigrate and 50,000 emigrate, what is the population?

Rule of 70: Doubling TimeCurrently, a city has a population 10 million. When will it reach 20 million if the population is growing at 10%?

How long will it take a population to go from 200 to 400 if it grows at 5% a year?

Section 1 ReviewDescribe how the size and growth rate for human population has changed over historyWhat factors lead to population changesAnalyze populations using Age Structure DiagramsTerms: Demography, Age Structure, Survivorship, Fertility, Migration, Life Expectancy

Population Age StructureFig. 10-14 p. 184

Section 2 : Population TrendsWhat are problems associated with rapid human population growth?Compare developed and developing (lesser developed) countries.Investigate strategies for reducing population growth.Terms: arable land, urbanization, suburban sprawl, developed and developing countries.

Problems With Rapid GrowthLack of infrastructure to support populationWater suppliesSewersRoadsSchoolsPowerplantsHospitalsHousing

Problems With Rapid GrowthUsing up resources too quicklyWater suppliesFood Supplies, VegetationWood/fuels : wood supplies critical to life in many regions

Problems With Rapid GrowthUnsafe water suppliesSewage mixing with water suppliesCholera, Dysentery, Typhoid 1 Billion lack clean water 3 million/yr die

Clean Water LackingIf the millions of women who haul water long distances had a faucet by their door, whole societies could be transformed.

Problems With Rapid GrowthLand becomes scarceArable land : land that can grow cropsTradeoffs made : agriculture, housing, natural habitats Which do you think typically wins out?

Problems With Rapid GrowthUrbanization: movement of people from rural areas to citiesMuch of world is going throughIncreased demand on infrastructure

Problems With GrowthIn U.S.Suburban sprawl: work in cities live in suburbsDecay of inner citiesIncreased trafficLoss of farmlandDecreased wildlife habitat

Suburban Sprawl

Diverse World PopulationDeveloped CountriesUS, Canada, Japan, Australia, New Zealand and most of Europe. High Per Capita GDP. (1.2 billion people)

Comparing a developed countrytoModerately DevelopedtoDeveloping (lesser developed)

Diverse World PopulationDeveloping (lesser developed) 5.2 billion people living with very little 97% of population growth.

Percent of WorldsDeveloping countriesDeveloped countriesPopulationPopulation growthWealth and incomeResource usePollution and waste19810.11.6851588127525

Most fertility rates are dropping toward replacement levels

Strategies for Controlling GrowthPublic AdvertisementsEconomic IncentivesLegal PunishmentsEmpowering WomenInvestments in Education and Family Planning

Growth Is Slowingbut still growing

Section 2 ReviewWhat are problems associated with rapid human population growth?Compare developed and developing (lesser developed) countries.Investigate strategies for reducing population growth.Terms: arable land, urbanization, suburban sprawl, developed and developing countries.