How Many People Can Earth Support

How Many People Can Earth Support - How Many People Can...

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How Many People Can Earth Support? Introduction o Talk about planet, how it has limitations and humans are pushing the boundaries of those limitations o Introduce topic of exactly how many people can earth support? This relies on what people are willing to accept as their quality of life. Americans have a very high quality of life, higher than any other nation. o Probably take the stance that we need to keep the human population under control, make a thesis statement on this Growing population o Statistics on how many people there are, were, are expected to be Historians estimate that total 50 billion humans have lived on earth at one time or another. Today, each second, three people are added to earth. (6) Four stages of human population growth (p57) First stage included first humans to the beginning of agriculture, sort of the end of the hunter gatherer era. Population density was 130-162 km2. Total pop less than a few million. Average growth rate 0.00011% Second stage includes from around 6000BC to the 1500AD. Pop density 1-2 persons per km2. Human pop up to 500 mill. Average growth rate about 0.03%. Third stage includes “machine age” 1500-1960. Total human pop now up to 3 billion. Average growth rate 0.1%. Fourth stage is currently where the total pop is about 6 billion and the average rate of growth is 1.4% o Reasons for the increase in population over the years In the beginning of humans, hunting and gathering kept the populations fairly low, had to move around a lot. Then agriculture started which gave a more reliable food source, and settled villages started to emerge around the world. This increased the population even more. Then over time, societies became more advanced, advances in medicine and sanitation cut down on deaths. The last major things to push the pop higher was the discovery of the cause of diseases, vaccines to prevent diseases, even better sanitation and medicine and the more efficient production of food through the use of machines and technology. (p57) o Growth rates of different countries and the discrepancies between them Growth rate is difference between the birth rate and death rate Growth rate of human race peaked in the late 1960’s at 2.1% and is currently 1.4%. Although it is declining, the worlds population is still growing at an exponential rate adding millions of people to the earth each year (p56)
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In developing countires the population growth rate is 1.6 but in developed nations it is more than often less than 1%, sometimes even a neg growth rate (p57) It seems the poorer a country the higher the birth rate which is bad because they cant support as many people. Also, “the more people, the greater the growth rate; the greater the growth rate, the more people.” (p60) o Population densities on land of planet earth (described above) o “Advocates of "sustainability" argue that increasing population and consumption are already causing damage to the planet, and that
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This note was uploaded on 03/08/2009 for the course BISC 102Lxg taught by Professor Kiefer,bakus during the Spring '06 term at USC.

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How Many People Can Earth Support - How Many People Can...

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