Population © Robert J. Atkins, Ph.D. 1

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What are six basic demographic (population) terms? Demography  The study of human population Fertility  Amount of childbearing in a population  Several measurements of this 3

Demographic terms (cont.) Crude birth rate  Live births per 1,000 people each year  High income nations e.g. U.S. = lower than average crude birth rate  The lower the average income, the higher the population increase 4

Demographic terms (Cont.) Fecundity rate  Maximum possible childbearing Sex Ratio  Males for every 100 females Zero Population growth (ZPG)  Two people produce two people  Maintains population at a steady state 5

Do you remember? What are the six basic demographic terms? What do they measure? 6

What is the world population? Currently  7 Billion Most of human history the population of the entire earth was 500 Million (1/2 billion) 7

Why do developing nations contribute so much more to the world population? Something to think about: 8

Why do people have so many children? Through most of human history:  Birth control was not reliable  Children were needed for the farm  High death rates = many children did not reach adulthood 9

What is the Malthusian theory? Food increasing arithmetically Pop. Increasing geometrically Result : People reproducing beyond what the planet can support  Out-stripping resources  Poisoning the planet 10

What is the Malthusian theory? Population Food Population increases geometrically Food increases arithmetically Population could increase beyond what the planet could support 11

What is the Demographic Transition Theory? Population patterns reflect a society’s level of technological development From preindustrial (high births & deaths) = slow population growth To postindustrial (low births & deaths) = slow or stable population growth Between these two, high birth rate & low death rate = rapidly expanding population 12

Do you remember? What is the current world population? Why did people have so many children? What is the Malthusian theory? What is the Demographic Transition theory? 13

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