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Today’s Agenda. Bellwork Chapter 3, Key Issues 1 -3 Reading Quiz Categorilla – pick up in the back of the room. What do you predict for the future of human population on Earth. Chapter 3, k 1-3 Reading Quiz. Pencil Pen 15 minutes. Bellwork : 09.24.2019.
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Today’s Agenda Bellwork Chapter 3, Key Issues 1 -3 Reading Quiz Categorilla – pick up in the back of the room
What do you predict for the future of human population on Earth
Chapter 3, k 1-3 Reading Quiz Pencil Pen 15 minutes
Bellwork: 09.24.2019 • Watch the National Geographic Video and take note of 3 to 5 major changes that have developed since the 1900s to now.
Population Key Issue 3
The Demographic Transition • Demographic Transition – process of change in society’s population form … • High CBR, High CDR, low NIR to • Low CBR, low CDR, low NIR, and higher total population • This occurs in four stages
Stage 1 • Very high birth and death rate produce virtually no long-term natural increase. • Most of human history is stage 1 • No country is currently in stage 1 because they have moved on to stage two and experienced significant population growth • Mostly hunters and gathers
Stage 2 • Characterized by rapidly declining death rates and very high birth rates creating a very high NIR • Europe and North America entered Stage 2 after 1750 because of • 1. The Industrial Revolution • Stage 2 Diffused to Africa, Asia, Latin America around 1950 because of the • Medical Revolution
Stage 3 • Birth rates rapidly decline, death rates continue to decline, natural increase rate begins to level off • Countries move to stage 3 when CBR begins to drop sharply, people have fewer kids because people live longer • Population still grows because CBR is higher than CDR but NIR is modest • People are more likely to lie in cities so they have less children so they don’t need as man children (like farmers do) • Europe and North America moved to stage 3 in 1st half of the 20th century • Latin America and Chile move to stage 3 during the 2nd half of the 20th century
Stage 4: Low Growth • Very low birth and death rates with no long-term NIR, maybe even a decrease • Zero population Growth (ZPR) • CBR = CDR, NIR less than or equal to 0 • CBR may be slightly higher but some females die before childbearing years • TFR doesn’t change total population • TFR at 2.1 produces ZPG • Women enter the labor force • Access to wide range of birth control
Declining Birth Rates • 1. lowering birth rates through education and health • 2. Lowering birth rates through contraception
Malthus on Overpopulation • Thomas Malthus (1798) – stated population growth would overrun food supply. Claimed population increases geometrically, food supply increases arithmetically. • Contemporary Neo-Malthusians • Agree with Malthus but think situation is worse because of recent population growth. • Now all countries have been in stage 2, lots of growth not a lot of production • Malthus’s Critics • Consider resources expanding • Larger population stimulates ability to grow more food and jobs • Just need to share resources
Malthus’s Theory and Reality • Population has grown but overall food production has also increased more rapidly • India – increased rice and wheat production faster
Population Future • Demographic Transition Possible Stage 5: decline • Because of continued low CBR the older population begins to crease CDR • NIR actually becomes negative (CDR)
China and India • The world’s two most populous countries, 1/3 of total population • India • 1947 rapid growth after independence from England • 1952 begins national family program (birth control abortions, sterilizations) • China • 1980 one child policy – prohibits marriage till in 20s, need permit to have children and hand out contraceptives, abortions, sterilizations • Law now is relaxed but still must pay to have more the one child