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November 28 - Mortality rates go up as population goes up...

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Human Regulation of Size How many Americans are dying of tobacco? 450,000 Cause of death has shift (because of anti-biotic) from disease to cancer/obesity Cardiovascular disease War: resources, religion, 3% of whole population killed off in war WW2—Russia 15million, 8% killed 30 (or 10) million people in Russia killed for political reason by Joseph Stalin Early agricultural societies: Intercourse avoidance Abortion Infanticide Abandon the elderly Fission—split large group in order to preserve resources and reduce competition Population growth World population size is 7 billion 10tya population was 100/200 million Agriculture started being practiced 6,000ya and populations grew (more food) Bubonic plague knocked out 1/3 of human population Then population grew exponentially There is no K yet, perhaps at 9 billion (perhaps this century) US: 300 million populations What determines if a population is growing? Mainly birth and death will dictate that Birth rate = density (size) dependent Birth rates go down as density goes up, per 1000 (not for the whole population)
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Unformatted text preview: Mortality rates go up as population goes up If the birth rate is bigger than the death rate, population will grow Birth rate decrease + mortality rate increase = population goes down When population size is small, there are more comings than goings When population increase, births go down and deaths go up When birth rate and death rate are equal, you reach the carrying capacity, K Birth rate and death rate Developed countries are growing slower Developing countries are growing faster; Africa is the fastest The greater the difference between birth rate and death rate, the greater is the rate of annual growth Annual rate of growth (Birth rate — death rate)/10 .7% — US How long does it take for populations to double? Rule of 70: 70/annual percentage of population growth Zimbabwe 70/3.5= 20 years This rule is assuming that it is a closed system—people aren’t coming or going...
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