Natural Change
and Migration shown as a comparison in the
Exponential Population Growth is shown on this Wikipedia page and is elaborated. The page gives many examples on how exponential growth occurs. Exponential models are also shown, and these are examples except in these models variables are taken into consideration giving a more realistic solution.
Population Concentration can be seen on this United Nations website. This interactive site allows you to choose the variable you want to view, the country or continent of your choosing, and the years that you set. The output comes in the form of a chart giving you the data you wish to see with the corresponding years.
Ten Largest Countries by population are on this page. Also on this page are the rest of the top 23 in population. All these countries have a population of over 50 million. However, these figures are estimates from mid-2006.
2. Population
Growth and Checks on Growth
Survivorship, also known as life expectancy, can be seen on this Wikipedia page. On the top of the page is a colorful world map showing the average life expectancy per country. Further down the page exists a line graph showing various life expectancies for certain regions. There is also a table showing the average lifespan for humans over the course of history. Finally, a formula is given to help calculate life expectancy.
Population Pyramids by country appear on this page. To view the population pyramids, select the country of your choice, then the type of output you want (summary of years, specific years, or a dynamic graph), and the size and hit ‘Submit Query’. The page will then let you view the pyramid for the specific country according to your input.
Demographic Transition is described on this page by many different graphs and charts. The demographic transition model is shown at the top of the page showing the four stages of the system. Other population trends that are shown on this site are population growth, survivorship, mortality and fertility rates, and various population pyramids. Overall, this page gives a great overview of population trends.
Malthusian Theory was conceived by Thomas Malthus and is the idea that the world can return to the subsistence-level agriculture way of life. Wikipedia sponsors this page and gives a more in-depth overview of this idea. The Neo-Malthusian Theory is also touched on and what that is. The last heading on the page gives an interesting perspective questioning if the theory is in effect today.
Logistic Population Curve is a mathematical equation that helps predict population growth. Several graphs appear on this page to give a visual rendition of the equations and show a general trend. A logistic trend, however, takes into consideration other factors that could disrupt population growth and provides a more real prediction.
Zero Population Growth (ZPG) occurs when the birth rate and the death rate in a country equal each other. The Wiki-site also makes the point that ZPG is hard to achieve because several economic factors have an effect on the rates and ZPG rarely occurs. This site also provides a link to the demographic transition page Mr. Peterson provides on his website.
Overpopulation is described on this National Geographic website. Using the sub-headings under the overpopulation header, you can navigate through different topics explaining various parts of overpopulation. These sub-headings are an Introduction, The Effect, The Phenomena, and The Science. On the Effect page, on the right sidebar is a link to see a series of satellite images showing some aspects of overpopulation. On the same side bar on the other pages are different fast facts as well as some audio from NASA or various video.
World Population at the current time is shown on this page. You can also compare the populations from year to year, and see what the population was on a given day. All in all, the population basically grows at three people per second.
U.S. Population
can be seen here from the U.S. Census Bureau. In big red numbers at the top of
the page is the current population in the
Submitted by Frank Hebert, Mike Golka, Camren LeFlore, Andrew Trent, and Charles Quigley on January 28, 2007.