Bell Ringer

Miniature Earth – If the population of the Earth were shrunk to just 100 people, but the proportions were kept the same, what would it look like? This video will show us.

http://www.schooltube.com/video/a6df161afdd345dab931/Miniature-Earth

POPULATION

What is Demography?

study of population

What is a primary tool of demographers?

Census- survey of population, done every 10 years by the federal government

What is Population Density?• The number of people in a unit of space.• Example: “8,500 people per square mile”

What is Population Distribution?

Habitable Lands - 2/3 of population between 20*N and 60*N

Urban-Rural Mix – ½ of population lives in cities, more each year

Migration – people moving, causes change in population

Push Factors – reasons people leave home

Pull Factors – reasons people come to new home

What is over population?number of people exceeds available resources

1)Eastern Asia has the greatest concentration of people on Earth – it is centered in China and has 21% of Earth’s population.

2) Southern Asia is the second largest concentration of

people – it is centered in India and has 16% of the Earth’s pop.

3) Western Europe is the third largest concentration.

In Western Europe people are concentrated near natural resources needed for industry.

4)East Central North America is the fourth largest center concentrated in the NE US and SE Canada.

In the US, the chain of cities start from the city of Boston to south of Washington DC.

- This is called a megalopolis.

Africa has 12% of the Earth’s population.

Largest cluster of people found in the Nile River Valley.

Cairo is the largest city in Africa.

South America is lightly populated compared with other continents.

Patterns of people live along the edges of the continent – SE Buenos Aires in Argentina, Montevideo in Uruguay, and Rio de Janeiro and Recife in Brazil.

Australia has the fewest number of people.

They are concentrated along the eastern and southern coasts.

(17.5 million people total on the entire continent. – as much as the NYC metro area)

North Pole

Population Growth Over Time “The J Curve”

During the Industrial RevolutionLate 1700’s to 1900’sNew technologies improved medicine, sanitation, and food production.

How do demographers determine who is growing?

Birth rates and Death rates

What are Birth Rates?Birth Rate – number of live births per 1000 people

Fertility Rate – average number of children a woman will have in her lifetime

What are Death Rates?Death (Mortality) Rate – number of deaths per 1000 people

Infant Mortality Rate – number of deaths among infants under 1 year old, per 1000 live births

What is Rate of Natural Increase?Rate of Natural Increase- % a population grows in one year

Birth Rate minus Death Rate

=

Rate of Natural Increase

What is Doubling Rate?Doubling rate- number of years it takes for a population to double.To figure the growth rate:

70 / Rate of Natural Increase (RNI)

=

Number of years to double population

Example: Mexico has an RNI of 1.7, so 70/1.7 = 41.17… so Mexico will double in population in about 41 years!

Gapminder

Use your laptop or iPad to go out to http://gapminder.org. Feel free to poke around and orient yourself before you start the Gapminder worksheet.

DEMOGRAPHIC TRANSITION

What is the Demographic Transition Model?

• Researchers identify either four or five stages of development.

• Complex line graph

• Categorizes a country based on birth & death rate

Determines:GrowthStandard of LivingLevel of industrialization

Stages of the Demographic Transition

ModelStage 1 – pre-industrial, slow growth rates

Stage 2 – poor countries, high birth and death rates

Stage 3 – developing countries, rapid growth

Stage 4 – developed countries, stable population

Stage 5 – rich and aging countries, shrinking population

Complex Bar Graph

What is shown?• Males and Females by age

Why?Demographers use age and sex to help predict info. about a country

How do population pyramids work?Wide base = high % of childrenNarrow base = low % of children

What is a Population Pyramid?

Making Predictions

Look at the shape of these charts, and think about them. Then try to answer these questions on a separate paper.

Which has a higher % of children?

Which is most wealthy, most poor?

Which has the most unemployed?

Which probably has best health care?

Which has most not going to school?

Projected U.S. Population Growth 1950-2050

Mexico Population Pyramid 1980- 2005

France Population Pyramid1990-2015