Demography - Sociological Imagination - Lecture Notes, Study notes of Sociology

Download Demography - Sociological Imagination - Lecture Notes and more Study notes Sociology in PDF only on Docsity! 1 CHAPTER 16 SUMMARY Changes in population, urbanization, and the physical environment are related. Population growth was one of the most significant changes of the 20th century. Since 1900, the world population has more than tripled in size. By the end of a typical day, in fact, the world increases by almost 219,000 people. Demography is the scientific study of human populations that examines size, composition, distribution, and the changes and causes of these characteristics. A population is a collection of people who share a geographic territory. Global population reached 1 billion in 1804, 5 billion in 1987, 6.5 billion in 2005, and is expected to rise to 9.4 billion by 2050. Fertility is the number of babies born in a particular society. The crude birth rate (CBR), also known as the birth rate, is the number of live births per 1,000 people in a population in a given year. Birth rates vary between and within populations. In the United States, younger women—those between ages 20 and 29— have higher birth rates than those ages 34 to 44, and recent immigrants have higher birth rates than the native born. The second reason for population change is mortality, the number of deaths in a population. Demographers typically measure mortality by the crude death rate (also called the death rate), the number of deaths per 1,000 people in a population in a given year. A better measure of a country’s health is the infant mortality rate, the number of deaths among infants under 1 year of age per 1,000 live births. Generally, as the standard of living improves—such as clean water, adequate sanitation, and access to medical care—infant mortality rates decrease. Infant death varies with 6.5 deaths per 1,000 live births in the U.S. and 163 in Afghanistan. Lower infant mortality greatly raises life expectancy, the average number of years that people who were born at about the same time will live. Worldwide, in 2008, the average life expectancy was 68 years—67 for men, and 70 for women. Life expectancy varies by access to clean water and health in general. Migration is the movement of people into or out of a specific geographic area. Migration is the product of two factors. Push factors encourage or force people to leave a residence because of war, political or religious persecution, natural disasters, unemployment, high crime rates, and a high cost of living. Pull factors attract people to a new location for the opposite reasons such as religious freedom, employment opportunities, better school systems, lower crime rates, and milder climates. International migration involves movement across a national border. Such migration includes emigrants (people who are moving out of a country) and immigrants (people who are moving into a country). Internal migration is the movement within a country. About 40 million Americans move within the United States every year. The proportion of men to women in a group in a nation’s population is a sex ratio. A sex ratio of 100 means that there are equal numbers of men and women, whereas a ratio of 95 means that there are 95 men for every 100 women. A population pyramid is a visual representation of the age and sex structure of a population at a given point in time. Mexico is a young country with many members 19 or younger. The U.S. is a middle country while Italy has a large population over 45. Population growth is occurring in less-developed countries. China and India have one billion people. Malthusian theory holds that the population is growing faster than the food supply needed to sustain it. This will lead to starvation. For Malthus, population grows at a geometric rate (2, 4, 8, 16, 32, 64, etc.) whereas the food supply grows at an arithmetic rate (i.e. 1, 2, 3, 4, 5, 6, etc.). Preventive checks such as war, famine, and disease can slow population growth. Recently neo-Malthusians continue to argue that the Earth is not going to sustain population growth. Another perspective on population argues that population growth is kept in check and stabilizes as countries experience economic development which, in turn, affects birth and death rates. The stages include preindustrial where there is little population growth due to natural checks. Stage two involves docsity.com 2 population expansion where couples have large number of children who live more often due to increased technology and declining disease rates. Much of the world is in stage two with expanding populations. Stage three involves drops in child death and fertility with women working outside the home. Finally stage four is based on low birth and death rates. Malthusian perspectives have been criticized for not predicting declining global fertility. Countries are experiencing zero population growth (ZPG), a stable population when each woman has no more than two children. While countries are trying to reverse declining population neo-Malthusians claim that by adding three billion people to the world in the next 30 years will put the planet at risk. A city is a geographic area where a large number of people live relatively permanently and secure their livelihood primarily through nonagricultural activities. Urbanization is the movement of people from rural areas to cities. In 2008, and for the first time in history, a majority of the world’s population lived in urban areas. By 2030, urban dwellers will make up roughly 60 percent of the world’s population. Early cities were based on protection. More recent urbanization has occurred due to industrialization. Today the pace of urbanization is centered in Asia, Latin American, and Africa. Between 1920 and 2007, the world’s urban population increased from 270 million to 3.3 billion, and is expected to rise to 6.5 billion by 2050. The world’s largest cities are becoming megacities, metropolitan areas with at least 10 million inhabitants. Current trends reveal that megacities are growing in developing countries where the urban poor are often crowded into slums, children are less likely to be enrolled in school, there is inadequate sanitation, and there is a widening economic gap between the haves and the have-nots. In the U.S, despite rapid population growth in parts of the U.S. south and west, 45 percent of all counties have lost population since 2000. Of the 1,346 counties that shrank in population between 2000 and 2007, 85 percent were rural. Rural communities are hard hit by population loss especially in the Midwest. Another major reason for urban growth is suburbanization, population movement from cities to the areas surrounding them. During the 1950s, suburbs mushroomed, attracting two-thirds of urban dwellers. The federal government, fearful of a return to economic depression of the 1930s, underwrote the construction of homes in the suburbs. Suburbanization has generated edge cities, business centers within or close to residential areas surrounded by businesses and services. Many live in bedroom communities and commute to jobs. As edge cities became more congested, people created exurbs, new areas beyond the suburbs that are more rural but at the fringe of metro areas. Urbanization has caused urban sprawl or unplanned growth and when the poor are pushed out gentrification or the process of buying and renovating house and stores by middle-class and affluent people in downtown urban neighborhoods. Explanations of urbanization include functionalism. In the 1920s and 1930s, sociologists at the University of Chicago developed theories of urban ecology, the study of the relationships between people and their urban environment. Models of urban change include concentric zone theory which explains the distribution of social groups within urban areas. According to this model, a city grows outward from a central point in a series of rings. The CBD or central business district is the innermost ring followed by a transition zone, then housing for the middle and working class. Finally the outermost ring is for suburbs and commuters. Another perspective is sector theory which postulates that cities develop in sectors instead of rings. Pie-shaped wedges radiate from the central business district depending on transportation routes (such as rail lines and roads) and various economic and social activities. Multiple-nuclei theory proposed that a city contains more than one center around which activities revolve. For example, a “minicenter” might include an outlying business district with stores and offices that are accessible to middle- and upper-class neighborhoods whereas airports typically attract hotels and warehouses. Thus, heavy industry and high-income housing centers rarely exist in the same part of the city. Peripheral theory argues that urban growth occurs with the development of suburbs around but away from the center of a city. docsity.com