Human Population 3

Factors Affecting Human Population Size

Demography Demography is the study of human populations. Information & Data are used to study human: immigration & emigration, population size, density, distribution, age structure, birth rates, and death rates.

Developed vs. Developing Countries In the past demographers have placed countries into two categories: developed and developing. Developed Countries – have a very strong varied industrial economies, stable infrastructure, and stable population size. (low birth rate) Developing Countries – have agrarian economies, little or not infrastructure, and unstable population size (high birth rate)

Developing Countries- China is the largest but has taken drastic population control methods. By 2050, India is predicted to pass it. Pakistan is projected to become 3rd with Iran and Ethiopia following. However, Russia is losing 600,000 people a year, after being the 4th largest country in 1950. This is because of environmental pollution, hyperinflation, crime, corruption, disease and despair.

FACTORS AFFECTING HUMAN POPULATION SIZE Average crude and birth rates for various groupings of countries in 2006. Figure 9-3

Average crude birth rate Average crude death rate 21 World 9 All developed countries 11 10 All developing countries 23 Figure 9.3 Global connections: average crude birth and death rates for various groupings of countries in 2006. (Data from Population Reference Bureau) 8 Developing countries (w/o China) 27 9 Fig. 9-3, p. 174

Africa Latin and Central America Asia Oceania United States North 38 15 Latin and Central America 21 6 Asia 20 7 Oceania 17 7 United States 14 Figure 9.3 Global connections: average crude birth and death rates for various groupings of countries in 2006. (Data from Population Reference Bureau) 8 North America 14 8 Europe 10 11 Fig. 9-3, p. 174

FACTORS AFFECTING HUMAN POPULATION SIZE The world’s 10 most populous countries in 2006 with projections in 2025. Figure 9-4

China 1.3 billion 1.5 billion India 1.1 billion 1.4 billion USA 300 million 349 million Indonesia 225 million 264 million Brazil 187 million 229 million Pakistan 166 million 229 million Bangladesh 147 million 190 million Figure 9.4 Global connections: the world’s 10 most populous countries in 2006, with projections of their population size in 2025. In 2006, more people lived in China than in all of Europe, Russia, North America, Japan, and Australia combined. By 2050, India is expected to have a larger population than China. (Data from World Bank and Population Reference Bureau) Russia 142 million 130 million Nigeria 135 million 199 million Japan 128 million 121 million 2006 2025 Fig. 9-4, p. 174

POPULATION AGE STRUCTURE The number of people in young, middle, and older age groups determines how fast populations grow or decline. The number of people younger than age 15 is the major factor determining a country’s population growth. Changes in the distribution of a country’s age groups have long-lasting economic and social impacts.

POPULATION AGE STRUCTURE Populations with a large proportion of its people in the prereproductive ages 1-14 have a large potential for rapid population growth. Figure 9-9

Expanding Rapidly Expanding Slowly Stable Declining Male Female Male Female Male Female Male Female Expanding Rapidly Guatemala Nigeria Saudi Arabia Expanding Slowly United States Australia Canada Stable Spain Portugal Greece Declining Germany Bulgaria Italy Figure 9.9 Generalized population age structure diagrams for countries with rapid (1.5–3%), slow (0.3–1.4%), zero (0–0.2%), and negative population growth rates (a declining population). Populations with a large proportion of its people in the prereproductive ages of 1–14 (at left) have a large potential for rapid population growth. QUESTION: Which of these diagrams best represents the country where you live? (Data from Population Reference Bureau) Prereproductive ages 0–14 Reproductive ages 15–44 Postreproductive ages 45–85+ Fig. 9-9, p. 179

POPULATION AGE STRUCTURE 32% of the people in developing countries were under 15 years old in 2006 versus only 17% in developed countries. Figure 9-10

Population (millions) Developed Countries Male Female Age Figure 9.10 Global connections: population structure by age and sex in developing countries and developed countries, 2006. (Data from United Nations Population Division and Population Reference Bureau) Population (millions) Fig. 9-10a, p. 179

Population (millions) Developed Countries Male Female Age Figure 9.10 Global connections: population structure by age and sex in developing countries and developed countries, 2006. (Data from United Nations Population Division and Population Reference Bureau) Population (millions) Fig. 9-10b, p. 179

POPULATION AGE STRUCTURE Today, baby boomers make up nearly half of all adult Americans and dominate the populations demand for goods and services. Figure 9-11

Expansive/rapid growth Birth rate exceeds the death rate. Population is getting larger. Pyramid shaped histogram. Ex’s. Kenya, Nigeria and Saudi Arabia.

Stable/Slow Growth (Zero Growth) Birth rate almost equals death rate. The population is not getting any larger or is growing very slowly. Histogram shape is straighter and more box-like until about age 45-85. Ex. US, Australia & Canada has slow Denmark, Austria and Italy has stable

Declining (negative growth) When the birth rate is smaller than the death rate. The pyramid bulges near the top or is inverted. Ex. Germany, Bulgaria & Hungary.

Hans Rosling: Population Growth, Box by Box. https://www.youtube.com/watch?v=fTznEIZRkLg&feature=share&list=PL7WxmjMiAYikNGKPUWeZxBNOhKsd8LxSo

Hans Rosling: Population Growth, Box by Box. https://www.youtube.com/watch?v=fTznEIZRkLg&feature=share&list=PL7WxmjMiAYikNGKPUWeZxBNOhKsd8LxSo

Declining Fertility Rates: Fewer Babies per Women The average number of children that a woman bears has dropped sharply. This decline is not low enough to stabilize the world’s population in the near future. Replacement-level fertility: the number of children a couple must bear to replace themselves. Total fertility rate (TFR): the average number of children a woman has during her reproductive years.

Case Study: Fertility and Birth Rates in the United States Nearly 2.9 million people were added to the U.S. in 2006: 59% occurred because of births outnumbering deaths. 41% came from illegal and legal immigration.

Case Study: Fertility and Birth Rates in the United States In 2006, the total fertility rate in the United States was slightly > 2.0 Figure 9-5

Replacement Level Baby boom (1946–64) Births per woman Replacement Level Baby boom (1946–64) Figure 9.5 Total fertility rates for the United States between 1917 and 2006. Use this figure to trace changes in total fertility rates during your lifetime. QUESTION: How many children do you plan to have? (Data from Population Reference Bureau and U.S. Census Bureau) Year Fig. 9-5, p. 175

Population Explosion Anything that causes the population to grow uncontrollably. Ex. Baby boom. 78 Million person increase between 1946-1964 (Men came home from the war. These people all had children and so this increase will continue to move up through the country’s age structure as members of this group grow older)

Case Study: Fertility and Birth Rates in the United States The baby bust that followed the baby boom was largely due to delayed marriage, contraception, and abortion. Figure 9-6

Births per thousand population Demographic transition End of World War II Demographic transition Depression Baby boom Baby bust Echo baby boom Figure 9.6 Birth rates in the United States, 1910–2006. Use this figure to trace changes in crude birth rates during your lifetime. (Data from U.S. Bureau of Census and U.S. Commerce Department) Year Fig. 9-6, p. 175

Question of the Day A population of 300 deer increases to 400 deer, the percent change in the population is _________. % Change = New Pop. – Old Pop. x100 Old Pop. 3% 33% 300% 50% 25%

Question of the Day Which of the following is the best description of a population that has a stable age distribution? A large population that is growing at a constant rate A large population with a negative growth rate A population that is in the early stages of logistic population growth A growing population in which the proportions of individuals in the different age classes remain constant A small population that has not yet achieved exponential growth