APHG Unit Two Review Population

Intro to Population The world’s population is currently greater than 6.5 billion people Population has been increasing for as long as humans have been on the planet During the last 100 years, the world’s population has exploded Population Explosion: a crisis in some LDC’s where the country’s resources cannot support the growing population

Demography The study of population characteristics is called demography Demographic statistics include:  Crude Birth Rate: the number of live births per 1,000 people in the population  Crude Death Rate: the number of deaths per 1,000 people in the population

Overpopulation Overpopulation is defined as the lack of necessary resources to meet the needs of the population of a defined area  Includes food, water, and shelter Carrying capacity: the ability of the land to sustain a certain number of organisms  Overpopulation occurs when the population exceeds the carrying capacity  Habitable land is called ecumene

The Five Too’s…again People tend not to live in areas where it is too hot, too cold, too hilly (two), too wet, or too dry Because of this, humans occupy a small part of the planet

Underpopulation Some parts of the world are underpopulated Underpopulation occurs when an area is sparsely populated and dominated by agriculture  Example: Midwest

Population Density Arithmetic Density: divides the population by land area; also called population density Physiological Density: divides the total population by the land used by humans Agricultural Density: the number of farmers divided by the amount of arable land

Malthus Thomas Malthus was a British economist who wrote in the late 1700’s He claimed that the rate of population was growing at a faster rate than food productivity  Malthus was first to use the term overpopulation His concern was that population was growing at exponential rate, and agricultural production was growing at linear rate

Types of Growth Linear Growth: growth that occurs evenly across each unit of time Exponential Growth: growth as a percentage of the total population Example: Imagine a village with 100 people with a 10 percent growth rate  Linear Growth: the population increases by ten every year  Exponential growth: the population increases by 10 the first year, 11 the second year, and so on After ten years, the first village would have 200. The second village would have 234.

Criticisms of Malthus Malthus was correct about the population growth, but not the agricultural production New inventions and technology increased productivity The world currently can produce enough food to feed itself neo-Malthusians: the theory that if there are multiple minority groups and no majority groups in a population, the growth rate will eventually resemble the growth rate of the fastest-growing group within the country  US will have exponential growth due to immigration

Demographic Transition Model Indicator of what will happen to a society or country’s population Based on three factors: the birth rate, the death rate, and the total population Has four or five stages Every country goes through each stage, and does not regress, unless disaster occurs

Stage 1: Hunting and Gathering Society has a low population High Birth Rate High Death Rate Population growth determined by food supply  When food abundant, people have more children  When food scarce, people abstain Examples: Aborigines of Australia

Stage 2: Agricultural Society Rapid population growth occurs Birth rates stay high Death rates decline sharply due to food sources and better medical care The majority of the population is involved in farming; mainly subsistence  Basic technology  Children seen as security Example: Liberia

Stage 3: Industrial Society Population growth still grows, but not as rapidly as in stage 2 Birth rates decline Death rates decline Industrial Revolution: began in the mid- 1700’s in Europe that allowed many countries to adopt mechanized system of farming  Children become liability instead of asset Example: Bolivia

Stage 4: Tertiary Societies Characterized by zero-population growth Birth rates equal death rates Society moves from industry to service based society  Natural Increase Rate is at or below 2  Some countries are experiencing negative population growth Example: Germany and Japan

More population statistics: Infant Mortality Rate: the number of babies per 1,000 that die before their first birthday Total Fertility Rate: the number of babies the average woman delivers during her childbearing years

Population Distributions Demography is not only about the population numbers, but about the characteristics of the population itself Sex ratio: the number of males compared to females in a population Population Pyramid: a visual representation of a country’s population

High, Slow & Negative Growth

Population Structure Population projections: make predictions of future populations Dependency Ratio: the number of people aged 0-14 or over 65 that rely on other people to take care of them Demographic momentum: a continued population increase as a result of a large segment of the population being young

More stats… Demographic Equation: the global births minus the global deaths and determines population growth for the world Doubling Time: the amount of time it will take the population to double in size Sustainability: saving resources for future generations so that they can live at the same or higher standard than people living today

Curves: J-Curve: developed by Ian Bremmer; places countries on a scale determined by their openness and stability; graphically illustrates the population explosion S-Curve: looks at population growth along the Demographic Transition Model

Population J-Curve

Population Increase: Medical Advances: New medicines and inoculations; disease diffusion does not occur as frequently as it used to Quantity and Quality of Food: increases in Agricultural technology have increased food supply Ethnic and Religious Issues: Birth control is forbidden in some religions Economic Issues: Population increases in agricultural society, and decreases in tertiary societies

Population Decreases Natural Disasters: Earthquakes, famines, and plagues can wipe out a large percentage of the population War or Political Turmoil: death by war and refugees Economic Issues: main reason people migrate is for economic opportunities