1. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Human Population

2. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings I. Intro to Human population growth: A. The current human population of earth is over 7 billion people. The population is rising by roughly 80 million people annually – which is 2.5 people per second. B. Populations continue to rise in most countries – the world growth rate is 1.2% -Particularly in poverty-stricken developing nations C. Although the rate of growth is slowing (it was 2.1% in the 1960’s), we are still increasing in absolute numbers D. The population of the United Sates is 314 million people (rounded to 300 million).

3. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

4. I. Intro to Human population growth E. The population is expected to reach 9 billion by 2050 F. The population is projected to level off at about 10 billion by 2,100 Due to exponential growth, even if the growth rate remains steady, population will continue to grow

5. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Falling growth rates do not mean fewer people G. Falling rates of growth do not mean a decreasing population, but only that rates of increase are slowing

6. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings II. Human Population Growth Over Time A.The history of human population growth can be viewed as consisting of four major periods: 1)In the early period of hunter/gathers, the world’s total human population was probably less than a few million. 2)A second period, beginning with the rise of agriculture, allowed a much greater density of people and the first major increase in the human population.

7. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings II. Human Population Growth Over Time 3) The Industrial Revolution, (1750’s – 1900) with improvements in health care, sanitation, and the supply of food, led to a rapid increase in population. Birth rates were high, but so were death rates as infectious diseases led to high infant and childhood mortality (measles, small pox, tuberculosis)

8. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings II. Human Population Growth Over Time 4) In the last 100 years, human population has expanded significantly. Vaccinations were developed in the late 1800’s, but came into wide-spread use in the 1900’s. Penicillin, the first antibiotic, was discovered in the 1930’s. Vaccinations and antibiotics greatly reduced the infant and childhood mortality rate. Since birth rates still remained high, populations began growing exponentially.

9. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings III. Demography A. Demography = the application of population ecology to the study of humans 1) Demographers study population size, 2) Density and distribution, 3) Age structure, sex ratio, 4) And birth, death, immigration, and emigration rates

10. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings III. Demography B. Environmental factors limit population growth C. Humans can raise the environment’s carrying capacity through technology -How many humans can the world sustain? 1 – 33 billion Ultimate sustainable human population size is unknown.

11. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings III. Demography D. Population Distribution - Increased density impacts the environment, but relieves pressure in less-populated areas E. Humans are unevenly distributed around the globe

12. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings F.Countries can be classified based on demographic factors: 1.Industrialized/urbanized/Developed/More economically advanced/High-Income - All terms used to describe countries that are generally urban, wealthy, and able to provide some social safety net services such as universal education, health care, and social security/pensions to the elderly. 2.Non-industrialized/more rural/developing/less economically advanced/ Low-Income – All terms used to describe countries that are generally less urban, more subsistence farming, poor, and usually unable to provide social services such as universal education, health care, and social security/pensions to the elderly.

13. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings III. Demography G. Total fertility rate (TFR) = the average number of children born per female H. Replacement fertility = TFR that keeps the size of a population stable – replacing the man and woman of the child 1)2.1 children per woman in developed countries is replacement fertility, higher value in developing countries, to account for infant/childhood mortality.

14. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 2) Infant mortality – number of children under 1 that die per 1,000 children under 1 in the population. 3) Childhood mortality - number of children under 5 that die per 1,000 children under 5 in the population. Country2014 Infant Mortality Rate (Per 1,000) Afghanistan117 India43 Brazil19 China15 United States6 Ireland4 Japan2

15. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings I. Increasing urbanization decreases Total Fertility Rate – Why? 1) Children go to school, and each child costs more 2) With social security, elderly parents need fewer children to support them 3) Children aren’t needed as farm/agricultural workers 4) Greater education allows women to enter the labor force, with less emphasis on child rearing

16. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings III. Demography J. Life expectancy = average number of years that an individual is likely to continue to live K. Life expectancy has increased as countries/the world has industrialized. -Increased due to reduced rates of infant/childhood mortality -Urbanization = better food/water/health care

17. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings L. Worldwide average life expectancy is 70 years (WHO, 2012), in the US it is 78. 1)Women have slightly higher life expectancies than men. 2)Between high-income and low-income countries, there is a life-expectancy gap of 16 yrs for men and 19 years for women. 3)Highest life expectancy in the world– men in Iceland – 81.2 years, women in Japan 87 years.

18. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings IV. Population Histograms A.Population Histograms are also called age structure diagrams, or population pyramids. B.These graphics show the number of males (left side of histogram) and females (right side of histogram) in each age cohort. Usually age cohorts are broken up into five year groups. Age pyramid of the U.S. in 2005

19. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings C. Population histograms show three big groups as well, which are sometimes color-coded 1.Pre-reproductive cohort – individuals in the population age 0-15 (red below) 2.Reproductive cohort – individuals in the population age 15-45 (orange below) 3.Post-reproductive cohort – individuals in the population over 45 (red below) Age pyramid of the U.S. in 2005

20. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings D. A lot can be determined about a country just by looking at it’s population histogram. There are three main types of population profiles. E. The first profile is of a country with a rapidly increasing population. If a country has more individuals in the pre- reproductive cohort than any other, it’s population will rapidly increase.

21. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings IV. Population Histograms F. This profile also indicates a high rate of infant/childhood mortality. There are many more individuals in the pre- reproductive cohort than the reproductive cohort, indicating that many individuals don’t make it to adulthood. G. Additionally, histograms like this also indicate a developing, or low-income country, with perhaps lower rates of health care and education for the population. Population growth is correlated with poverty, not wealth

22. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings IV. Population Histograms H. Benefits to this population profile would be greater population of workers/farmers for a country. I. Challenges to this population profile would be providing education, health care, and housing for all of the country’s population. Examples include: Many African countries, Afghanistan

23. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings IV. Population Histograms J. The second type of population profile is for a country with a stable population. There is almost no change in number of individuals between the pre-reproductive and reproductive cohort.

24. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings K. This is considered somewhat ideal for a country – enough resources for education and health care for the current population, but no shortages of workers for the future.

25. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Example countries include the United States, France, the UK, and Iceland.

26. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings IV. Population Histograms L. The third type of population profile is for a country with a decreasing population. There are fewer individuals in the pre-reproductive cohort than in the reproductive cohort.

27. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings M. Benefits for this population structure include less cost for the country for education, and lower crime rates. N. Challenges include fewer workers, and perhaps lower GDP. Additionally the elderly tend to have higher health care costs and draw from Social Security, also increasing tax burdens for these services. O. Countries with this type of population structure have started to offer incentives to women/families to have more children.

28. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Examples include Japan, South Korea, and many western European countries like Italy and Spain.

29. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings V. The demographic transition A. Demographic transition = a model of economic and cultural change to explain the declining death and birth rates in industrializing nations B. Stable preindustrial state of high birth and death rates change to a stable post-industrial state of low birth and death rates

30. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The demographic transition’s four stages

31. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings V. The demographic transition C. Four main phases to the demographic transition: 1) Phase I (Pre-Industrial): A high crude birth rate and a high crude death rate means the population does not grow 2) Phase II (Transitional): A declining crude death rate due to medical advance along with continued high crude birth rate means the population explodes 3) Phase III (Industrial): Although the fertility rate declines as the country becomes industrialized, the population growth is still significant 4) Phase IV: In the post-industrial phase, both birth and death rates are low.

32. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings V. The demographic transition D. The demographic transition is a population transition that most industrialized nations have gone through. Most European nations passed through Phase II during the 18 th and 19 th centuries (Industrial Revolution).

33. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings E. Is the demographic transition universal? 1) It has occurred in Europe, U.S., Canada, Japan, and other nations over the past 200-300 years 2) But, it may or may not apply to all developing nations 3) The transition could fail in cultures -That place greater value on childbirth or -Grant women fewer freedoms

34. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings VI. Calculating Population Change A.Three main things you need to be able to calculate for populations are population change (which we learned last time),the growth rate, and doubling time. B.The growth rate of a population (g) is (B-D)/N Where B = total number of births D = total number of deaths And N = the total number in the population. C. Growth rate is usually expressed as a percentage, so multiply your value by 100 to get a percent

35. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings D. You can also calculate growth rate for a country if you are given the crude birth (CBR) and crude death (CDR) rates. Crude rates are rates per 1,000 people in the population. So crude birth rates are the number of births per thousand people in the country’s population. Annual growth rate = (CBR – CDR) / 10 *The answer is already in percent, so whatever number you get is the annual growth rate percent!

36. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings V. Calculating Population Change E. The doubling time is the amount of time it will take for the population to double in size. A rough formula (the one you will use on your AP test instead of the log formula) is the rule of 70, where T = 70/annual growth rate Where T = doubling time (in years) And Annual growth rate is expressed in as a percentage.