The Demographic Transition Blowin Up yo THE DEMOGRAPHIC
The Demographic Transition Blowin’ Up, yo.
THE DEMOGRAPHIC TRANSITION In Human Geography, a “model” is a theory that a geographer (or geographers) have developed to predict some form of human behavior. Reality will never look exactly like the model, but models reflect what reality “looks like. ” The Demographic Transition (DT) is a model that predicts patterns of population growth and trends in countries as they develop. The DT tracks three demographic variables that are tied to and result in population change: crude birth rate (CBR)… births / 1000 people crude death rate (CDR)… deaths / 1000 people Natural Increase Rate (NIR)… % pop growth/yr The DT is divided into four stages that address what is happening to a country’s population in each: --STAGE 1: Low Growth --STAGE 2: High Growth --STAGE 3: Decreasing Growth --STAGE 4: Low Growth
STAGE 1: LOW GROWTH STAGE 1 is called “low growth” because a country’s population is relatively stable or growing only very slowly. All countries were in STAGE 1 at some point before they gained industrial or medical technology that helped people live longer. In terms of the model and its predictions… CDR CBR NIR HIGH AND FLUCTUATING (upper 30 s to lower 40 s) LOW AND FLUCTUATING (Around 0%) …because food supplies were unstable, even after the agricultural revolution …because many children died early and families needed many children to help with hunting/gathering or FARMING …because the CBR and CDR were roughly equal. …because of lack of basic sanitation and hygiene …because of a lack of contraception THEREFORE, population was relatively stable. …because of a lack of medical technology The entire planet was in STAGE 1 for most of human history, and the global human population was relatively low at about 50 million humans, all told. TODAY, there are NO countries in STAGE 1 because one of two technologies has arrived in all countries…
STAGE 2: HIGH GROWTH STAGE 2 is called “high growth” because a country’s population grows drastically in this phase. There are TWO reasons that a country will enter STAGE 2, it enters either: THE INDUSTRIAL REVOLUTION or THE MEDICAL REVOLUTION. In either case, the death rate drops steeply. When a country’s CDR drops (never to reach high levels again), it is said to have entered STAGE 2. CDR DROPS STEEPLY (FROM upper 30 s & lower 40 s TO mid teens) CBR HIGH AND FLUCTUATING (upper 30 s to lower 40 s) NIR INCREASES DRASTICALLY (FROM around 0% TO around 3% annually) INDUSTRIAL REVOLUTION: It began in England bringing major advances in machine technology, much of which centered on farming. …because the CBR greatly exceeds the CDR. The IR generated massive wealth and put many farmers out of jobs. Those farmers moved to cities (“urban centers”) to work in factories making machines. THEREFORE, POP grows rapidly because way more people are born than die each year. Those urban centers developed water and sewer systems and people were able to have better hygiene. Better hygiene = less death. Less death = population increase (if the birth rate remains unchanged). The countries of Europe and North America entered STAGE 2 early, industrialized and are now “MDCs. ” THE MEDICAL REVOLUTION: It began in 1950 as MDCs developed medical technology to fight most major diseases. Countries that had not industrialized (LDCs) obtained the medical technology for their citizens. While birth rates remained high (because the countries were not industrializing and farming families need many children to work the land) death rates dropped. Less death= population increase. ALL countries that have industrialized (MDCs) have moved out of STAGE 2. Countries that have not industrialized or or only beginning to (LDCs) are STUCK IN STAGE 2.
THE EMPHASIS CDR fell in North American and European countries because of industrialization: A. Farms got machines, excess farmers moved to cities to work in factories B. Wealth began to spread… better living conditions, better nutrition from farms, better sanitation systems, better hygiene and medicine… LESS DEATH CDR fell in African, Latin American and Asian countries FOR A DIFFERENT REASON. The MEDICAL REVOLUTION from wealthy countries (not industries) diffused: A. better hygiene and medicine… LESS DEATH The GAP between high CBR and low CDR means MORE PEOPLE
STAGE 3: DECREASING GROWTH STAGE 3 is called “decreasing growth” because a country’s NIR is still well above zero (therefore population growth), but the NIR is also dropping (less and less positive) so the growth rate is slowing down (decreasing). For example: dropping from 3% (NIR of 3) to 2% (NIR of 2). The NIR decreases for only one reason: the crude birth rate begins falling drastically. CDR CBR CONTINUES DROP (slight) (FROM mid teens TO mid single digits) DROPS STEEPLY (FROM upper 30 s & lower 40 s TO mid teens) In STAGE 2, the CDR dropped because of a change in technology (Industrial or medical). In STAGE 3, the CBR drops because of a change in society: NIR STEEP DROP BUT STILL POSITIVE (FROM around 3% TO around 1% annually) …because the CBR is rapidly approaching the CDR THEREFORE, POP growth Large families had moved to cities with cramped apartments. remains positive but is On a farm, children are an financial asset, but in the city, they much less rapid. are a financial burden (cost money but cannot bring in money). Also, in the countryside, a family needed to have 10 children to keep six (high death rates) but in the city, almost all of the children born will live. THEREFORE, families automatically decide to start having fewer children. European and North American countries entered STAGE 3 in early 1900 s. Many Asian and Latin American countries entered recently. Most African countries remain in STAGE 2.
THE EMPHASIS This isn’t what I meant when I asked for a room with a view. In Stage 2, CDR dropped because of change in TECHNOLOGY: • Industrial technology in MDCs • Medical technology in LDCs In Stage 3, CBR drops for a different reason, a change in SOCIETY: • People choose to have fewer children • Since more babies live from stage 2’s CDR drop, couples have fewer children • Since fewer people work on farms and more in factories, fewer children is better • Since urban homes are smaller, fewer children can fit. Many people are trading rural life for a smaller-scale urban life. I should have used birth control.
STAGE 4: LOW GROWTH STAGE 4 is called “low growth” because a country’s Birth Rate finally catches back up to is Death Rate and is roughly equal to it. Therefore, the NIR approaches 0% (NIR of 0). An NIR of zero is called zero population growth (ZPG) because the population is roughly constant (or only very slightly positive). To achieve ZPG, a country’s Total Fertility Rate (TFR… the average number of children that a female will have in her reproductive years) will equal 2. 1 The NIR continues to decrease for only one reason: the crude birth rate continues to fall. CDR SLIGHT INCREASE (FROM mid single digits TO HIGH SINGLES) CBR SLIGHT DROP (FROM mid teens TO upper single digits) The CDR sees a slight uptick because people are living just about as long as a body can. And since a large number of people are reaching old age, the CDR increases slightly. NIR DROPS TO ZERO …because the CBR is roughly equal to CDR THEREFORE, POP growth flattens The CBR continues to drop because of a further social change. As a country continues to develop, women gain access to education. They stay in school longer, therefore get married later, therefore have fewer children. Educated women also pursue careers and earn their own money. Because they pursue careers, they get married later, therefore have fewer children. Also, better birth control, the high cost of child care and many couples enjoy the “DINK” lifestyle.
Okay, hots… Quiz time. Which countries are in stage 4 of the Demographic Transition? Don’t Be Fooled: Not all countries with a TFR of 2. 1 or below are stage 4 countries. • Some have high CDRs • Others have strict anti-natal policies
THE EMPHASIS Countries enter stage 3 because of a change in SOCIETY. Countries also enter stage 4 because of a change in society: • • • More women are educated and educated longer (delayed childbirth) More women pursue careers (delayed childbirth) Daycare is expensive (fewer children) Better access to birth control (fewer and delayed children) Increased wealth and leisure = recreation (delayed children) …Think of all those poor schmucks with kids! …heh, Morons.
STAGE 5: POPULATION DECLINE STAGE 5 is a POSSIBLE, EVENTUAL stage of the Demographic Transition. STAGE 5 is called “population decline” because a country’s Birth Rate continues to drop and its Death Rate continues to increase. Eventually, the CBR is lowed than the CDR. Therefore, the NIR goes negative (population loss). This combination of events happens for a few reasons. CDR CBR NIR SLIGHT INCREASE (FROM high singles TO low teens) SLIGHT DROP (FROM upper single digits TO mid singles) GOES TO NEGATIVE …because the CBR is below CDR THEREFORE, POP starts to DROP The CDR continues to rise because an increasingly larger percentage of the population is elderly (and death rates are higher among the elderly). It is also possible that new, “super pandemics” emerge… think bird flu, swine flu, MERS, etc. The CDR stays low or gets slightly lower because many couples decide to have only one or to have no kids “The Child-Free Life. ” JAPAN is currently facing a bit of a population crisis and a possible STAGE 5.
DTM based on historical patterns in Western Europe
When IMR declines, fertility rates drop soon after
Rapidly increasing urbanization in world LDCs today Population Classified as Urban
Strong inverse relationship between female literacy and fertility rates, observed globally Increasing availability and use of modern contraception in most LDCs since 1970 s
Differences in DTM experience: MDCs & LDCs ● Faster decline in death rates — Tech improvements diffused from MDCs & applied rapidly in LDCs post-WW 2 ● Longer lag between decline in deaths and decline in births — Stage 3 slower start in LDCs where econ growth is delayed ● Higher max rates of growth in LDCs — Over 3. 5% peak NIR in Mauritius and Mexico; only 1. 3% peak in Sweden
Age structures today in LDCs are much younger than MDCs experienced – leading to prolonged “Demographic Momentum” – expected growth of pop. long after fertility declines Percentage of Population Under Age 15
Country China BR DR Stage France 13 9 4 Afghanistan 43 16 Late 2 Kenya 35 8 Late 2 / Early 3 India 22 7 Middle 3 Germany 8 10 4 or 5 China 12 7 4
Hidden Momentum • Kuby example
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