Human Population

So what is the “typical” human like?

I. Where in the world do people live and why?

Population density: a country’s total population relative to land size

• Assumes an even distribution of population to the land

​

The World Today: 8 Billion & Counting

• About 50% of the world’s people are urban (living in or near cities).
• 90% of the world’s people live north of the Equator.
• 80% live at less than 500 meters (1,640 feet) elevation.
• ⅔ live within 500 km (310 miles) of an ocean.
• ¾ of the world’s people live on 5% of the Earth’s surface.
• 90% live on 20% of the Earth’s land.
• ECUMENE: the inhabitable part of the planet

The 4 (+1) Major Population Clusters

EAST ASIA

• About 1.7 billion people
• Nearly 25% of humanity
• 15% of humanity in China alone (about 1 in 6 people)
• About ⅔ rural

Seoul, South Korea

The 4 (+1) Major Population Clusters

SOUTH ASIA

• About 2 billion people
• Nearly 25% of humanity
• 15% of humanity in India alone (about 1 in 6 people)
• About ¾ rural

Dhaka, Bangladesh

The 4 (+1) Major Population Clusters

EUROPE

• About 750 million people
• Nearly 10% of humanity
• Mostly urban (75%)

London, United Kingdom

The 4 (+1) Major Population Clusters

SOUTHEAST ASIA

• About 700 million people (150 million on the island of Java alone)
• 9% of humanity
• Mostly rural

Jakarta, Indonesia

The 4 (+1) Major Population Clusters

EASTERN N. AMERICA (just for perspective)

• About 130 million people (major cities of USA & Canada)
• Just 2% of humanity (US & Canada combined are only 5%)
• Mostly urban (90%)

Toronto, Canada

The 4 (+1) Major Population Clusters

The 4 (+1) Major Population Clusters

• MEGALOPOLIS: super-cities, or the melding of nearby cities

How did these areas get this way?

How did these areas get this way?

Demography: the study of population

• Density is the measure of “how many per”

The question is: What are we interested in finding out?

• Different density measures give us different insights, such as:
• Level of development
• Type of economy
• Clues about population growth, health, racial & ethnic groups, treatment of women, etc.

Demography: the study of population

• Arithmetic Population Density: measure of total population relative to land area
• High arithmetic density can mean two things: 1)Many people or 2) Little land
• (Total population) / (Total land area)
• US population = ~340,000,000
• US land area = 9,161,923 km²
• (320,000,000) / (9,161,923) = ~37 inhabitants/km²

ARITHMETIC DENSITY EXAMPLE:

Malawi vs. Ecuador

• Population very close (both 13.9 million)
• Total area different (Malawi 118,480 sq. mi., Ecuador 283,560 sq. mi.)
• Malawi: 13,900,000 / 118,480= 117
• Ecuador: 13,900,000 / 283,560= 49
• Malawi’s density: 117 people per sq. mi. VS. Ecuador’s density: 49 people per sq. mi.)
• What does arithmetic density tell us that crude population cannot?

​

Demography: the study of population

• Physiological Population Density: population per unit area of agriculturally productive land
• The larger the physiological density, the larger the pressure people place on the land to produce food.
• (Total population) / (Total arable land area)
• US population = ~340,000,000
• US arable land area = ~1,650,000 km²
• (340,000,000) / (1,650,000) = ~200 inhabitants/km²

Percent Arable Land per Country

Only 2% of Australia’s population lives in the yellow areas

Half of the USA lives in one of these 146 counties

PHYSIOLOGICAL DENSITY EXAMPLE:

Egypt vs. USA

• What doesn’t arithmetic density tell us about the land a population occupies?
• Egypt: 3503 person per km² of arable land
• United States: 200 persons per km²
• What does this mean?
• Demonstrates that crops grown on an acre of land in Egypt must feed far more people than an acre in the U.S.
• The larger the physiological density, the larger the pressure people place on the land to produce food. (video to minute 5:00)

​

Demography: the study of population

• Agricultural Population Density: farming population per unit area of agriculturally productive land
• (Total farming population) / (Total arable land area)
• US population living on farms = ~4,600,000
• US arable land area = ~1,650,000 km²
• (4,600,000) / (1,650,000) = ~2.78 farmers/km²

Cotton Farms: USA vs. India

AGRICULTURAL DENSITY EXAMPLE:

Egypt vs. USA

• If two countries have similar physiological densities, but produce different amounts of food, what could account for this?
• Ratio of farm dwellers to arable land:
• Egypt: 1401 farmer dwellers per km² of arable land
• United States: 2 farm dwellers per km²
• What can we conclude about technology and/or economic conditions if agricultural density is low? If it’s high?

Arithmetic VS Physiological VS Agricultural Density

DENSITY PRACTICE QUESTIONS

Arithmetic Density

• U.S. (35 per sq. km) vs. Canada (3 per sq. km)
• Which has either more people or less land?

Physiological Density

• India (559 per sq. km) vs. Japan (3,054 per sq. km)
• Which puts more pressure on the land to produce enough food?

Agricultural Density

• Netherlands (64 per sq. km) vs. Bangladesh (883 per sq. km)
• Which country has a more efficient agricultural system?

II. Why Do Populations Rise and Fall in Particular Places?

• Thomas Malthus An Essay on the Principles of Population (1798)
• Population grows EXPONENTIALLY
• Food supplies grow LINEARLY
• Population growth will eventually outpace the food supply. War, disease, famine (through laissez-faire) are needed to control the population.
• The poor must have less children or they will die off as food supplies stabilize.

Overpopulation: Fact or Fiction?

Overpopulation: Fact or Fiction?

So what happened?

• Expansion of food supply sources (globalization)
• Exponential increase in agricultural productivity

(Modern) Neo-Malthusians

• retain concerns about overpopulation
• advocate population control measures

Overpopulation: Fact or Fiction?

• Doubling Time: Number of years for a population to double
• Past century: Human population has experienced decreased doubling time (rapid growth) then increased doubling time (slowed growth)

Overpopulation: Fact or Fiction?

• The Rule of 70: 70 / Rate of Increase = Doubling Time
• Using compound interest, this equation allows you to simply and quickly calculate doubling time

Overpopulation: Fact or Fiction?

• Rate of Natural Increase: Difference between births & deaths (not including immigration and/or emigration)

Overpopulation: Fact or Fiction?

Overpopulation: Fact or Fiction?

• Total Fertility Rate (TFR): average number of children per woman

TFR required to maintain population in developed nations? 2.1

Total Fertility Rate

World Birth Rate (births per 1000 people)

Why is TFR a more accurate measure?

Overpopulation: Fact or Fiction?

• The Demographic Transition: A decline in death rates is often followed by a decline in birth rates, resulting in a low or stable growth rate.

4 Stages of Demographic Transition

1. High Stationary: A high mortality rate accompanies a high birth rate
2. Early Expanding: Mortality rate falls rapidly (science, medicine, etc.) as birth rate remains high (tradition)
3. Late Expanding: Mortality rate continues to slowly fall as it begins to stabilize, while birth rates fall dramatically
4. Low Stationary: A low mortality rate accompanies a low birth rate
5. Declining???: Low mortality rate continues as birth rate falls below population sustaining levels (possible growth again later?)

4 Stages of Demographic Transition

1. High Stationary: Pre-Industrial & Pre-Agricultural Revolution
• High birth/death rate
• Fragile, but stable, population

4 Stages of Demographic Transition

2. Early Expanding: Improved Agriculture & Medicinal Use

• lower death rate & lower infant mortality (population boom)
• ex. Afghanistan, Yemen, Iraq, most of sub-Saharan Africa (except Botswana, South Africa, Gabon, Kenya, & Ghana)

4 Stages of Demographic Transition

3. Late Expanding: Attitudes towards family size begin to change

• indicative of countries becoming more developed/richer
• higher standards of living/education (birth rate falls)

Youth Bulge!

4 Stages of Demographic Transition

4. Low Stationary: Developed nations with high education levels

• mainly urbanized population
• most have luxuries/amenities and disposable income
• A possible shift to Stage 5 in the next generation or so

5 Stages of Demographic Transition

5??? Declining???: Highly educated and developed economy

• Too much family planning?? Too career/education oriented? Ex?? South Korea, Japan, Germany, most of Europe??

Future change in social norms? Increased fertility? Forced fertility?

​

Japanese Population

III. Why Does Population Composition Matter?

• Population Pyramid A graphic depiction of population by divisions in:
• AGE GROUP
• Divided by DISTRIBUTION OF SEX

Population Pyramids

Population Pyramids (Developing Countries)

• High infant mortality & Short life expectancy
• Rapid Population growth leads to a “Pyramid” shape

Population Pyramids (Youth Bulge)

• Countries in Stage 3 typically experience a Youth Bulge

Population Pyramids (Global Youth Bulge?)

Population Pyramids (Wealthy Countries)

• Low infant mortality & Long life expectancy (especially for females)
• Little or no growth (possibly negative) leads to a “Rectangle” shape

Higher stages of Demographic Transition typically reflect more opportunities for women, but not necessarily gender equality

IV. How Does the Geography of Health Influence Population Dynamics?

The Geography of Health

CHRONIC/DEGENERATIVE DISEASES represent longer life expectancies

COMMUNICABLE DISEASES represent shorter life expectancies

Infectious Diseases

VECTORED spread by a “vector” (mosquito, tick, snail, fleas, etc.)

NONVECTORED (HIV/AIDS, Covid-19, etc.).

Effects of USA’s withdrawal from WHO and USAID?

Infant Mortality Rate

(deaths per 1000 children under the age of one)

Maternal Mortality Rate

(maternal deaths per 100,000 pregnancies)

V. How Do Governments Impact Population Change?

• Expansive population policies: Encourage large families and raise the rate of natural increase
• Eugenic population policies: Designed to favor one racial or cultural sector of the population over others

What About Religion’s Impact?

• Irony?? The closer you get to the Vatican (opposes birth control), the lower the birth rate
• Irony?? Muslim countries, some of the most religious in the world, have experienced the fastest decrease in birth rate

​

The UNIQUE CASE OF CHINA

• One Child Policy: instituted in 1979 at the end of Mao’s rule
• Increased abortion, infanticide, orphans, adoption
• 1979-2015: Demographers estimate a loss of 400 million population
• Social Engineering has resulted in age and gender imbalances

​

The UNIQUE CASE OF CHINA