Demographic Data of World Populations:

Demographic Data and Construction and Interpretation of Related Graphs

Part A. Working with Demographic Data

Purpose: The purpose of this assignment is to develop a working vocabulary for population geography, to recognize the relationships and implications of demographic data, and to analyze population pyramids at different scales.

Additional Information on Populations: As Molles (2010) states, “population growth is the change in population over time.” Population growth is often used informally for the more precise phrase ‘population growth rate’, which refers, specifically, to the human population of the world. As Molles (2010) also mentions, “age distribution is the percentage of the total population, or the population of each sex at each age level.” Something interesting that relates to age distribution is the term age-dependency. For example, in some, usually less developed countries, the majority of the human population is either younger than 15 years of age or older than 65, causing the people to have no one to rely on to keep the economy running. This leads to economic depression. Lastly, as Molles discusses, population dynamics are the short and long term changes in the size and age compositions of populations, depending on birth and death rates, as well as immigration and emigration. It is interesting to study these population demographics because they can give the researcher an abundance of information on a specific country. For example, once the birth and death rates of a country are determined, one can calculate the infant mortality rate as well establish how industrialized, developed and economically stable a country is or isn’t.

Table 1- Annual Population Growth:

Country Number of People added annually
China 6,690,000.0005
India 17,820,000.012

Table 2- Populations in Proportion to the World’s Population:

Continent % Living Today % by 2025 % by 2050
Asia 60.3% 60% 57.2%
North America 5% 4.8% 5%
Latin America 8.5% 8.2% 7.7%
Europe 10.7% 9.2% 7.6%
Oceania 0.54% 0.56% 0.61%

Graph 1- Bar Chart of Table 2:

*See Email (I could not seem to copy and paste it here)

Question 1- What trends are reflected in the bar chart?

Calculations: In table 2, the percents were calculated by dividing the population of a specific continent in a given year by the total world population in that same given year. For example, for North America in 2010, we divided 344 (in thousands), the current population of North America, by the current total world population of 6,892 (in thousands). We then changed the number into a percent.

Answer: The bar chart shows that Asia will have the highest increase in population by 2025 and 2050, but has decreased from the current population today.

Table 3- LDC/MDC Populations in Proportion to the World’s Population:

Countries % of World’s Pop. Today % of World’s Pop. 2025 % of World’s Pop. 2050
LCD: Ethiopia 82.1% 84.1% 86.0%
MCD: Sweden 18% 16% 14.1%

Question 2- Discuss the economic and the social implications of the changing proportions of the world’s population in less developed countries and in more developed countries.

Calculations: In table 3, the percents were calculated by dividing the population of a specific country in a given year by the total world population in that same given year. We then changed the number into a percent.

Answer: In more developed countries there is more money and more education available, therefore the people are aware that the population needs to be regulated, so there is significantly less of an increase in population. In less developed countries there is less money and less education, therefore they have a much higher rate of population increase.

Table 4- Calculating Rate of Natural Increase:

Country CBR % CDR % Rate of Natural Increase (%)
US 1.4% 0.8% 0.6%
Greece 1.1% 1.0% 0.1%
Spain 1.1% 0.8% 0.3%

Question 3- Discuss the mathematical relationship between the crude birth rate, the crude death rate, and the rate of natural increase.

Calculations: To calculate the rate of natural increase, we took the difference between the crude death rate and the crude birth rate in. For example, from the US, we subtracted the CDR of 8 from the CBR of 14 to get 6, and then divided by 10 to get 0.6% for the rate of natural increase.

Answer: The rate of natural increase is the difference between the crude death rate (CDR) and the crude birth rate (CBR).

Table 5- Calculating Age-Dependency Ratios:

Country Age-Dependency Ratio
LCD 1: Burundi 78.6%
LCD 2: Ethiopia 88.7%
MDC 1: UK 51.5%
MDC 2: Sweden 53.8%

Question 4- A) What factors do you think contribute to a high age-dependency ratio? B) What are some economic and social consequences of a high age-dependency ratio?

Calculations: To calculate the age-dependency ratio of a specific country, we added the percent of the population of that country with less than 15 years of age to the percent above 65 years of age and then divided that number by the total percent of the population ages 15-64. We then multiplied that final number by 100 and converted the final number into a percent.

Answer A: Factors that contribute to a high age-dependency ratio are less education and less money, therefore less developed countries have higher age-dependency ratios.

Answer B: With a high age-dependency ratio, there are too many people below the age of 15 and too many above the age of 64, therefore there are not enough people to support the economy and there is no one to rely on. This leads to a social economic crisis.

Part B. Interpreting Age-Sex Graphs

Demographic Data: We will investigate the demographic data for the United Kingdom from Column A and Ethiopia from Column B.

Table 6- Demographic Indicators for the United Kingdom:

Demographic Indicators Value
Total Midyear Population 62348447
Crude Birth Rate (per 1,000) 12 %
Crude Death Rate (per 1,000) 9 %
Natural Increase (%) 0.6 %
Infant Mortality Rate (per 1,000 births) 5 %
Total Fertility Rate 1.9 %
Life Expectancy at Birth for Males 77.84
Life Expectancy at Birth for Females 82.11
Population <15 yrs. (%)/ >65 yrs. (%) <15 = 18 % 

>65 = 16 %

GNP/capita (US $) $36,130

Graph 2- Age-Sex Pyramid for the United Kingdom:

*See Email (I could not seem to copy and paste it here)

Table 7- Demographic Indicators for Ethiopia:

Demographic Indicators Value
Total Midyear Population 88,013
Crude Birth Rate (per 1,000) 43 %
Crude Death Rate (per 1,000) 11 %
Natural Increase (%) 3.2 %
Infant Mortality Rate (per 1,000 births) 79 %
Total Fertility Rate 6.1 %
Life Expectancy at Birth for Males 54
Life Expectancy at Birth for Females 57
Population <15 yrs. (%)/ >65 yrs. (%) <15 = 44 % 

>65 = 3 %

GNP/capita (US $) $870

Graph 3- Age-Sex Pyramid for Ethiopia:

*See Email (I could not seem to copy and paste it here)

Question 5- Compare the demographic indicators from the two countries you chose. What generalizations can be made concerning demographic indicators and level of development?

Answer: It is clear by examining the demographic indicators of both the United Kingdom and Ethiopia that the United Kingdom is a much more developed country than Ethiopia. This is clear because, as one can see from the tables and graphs above, the United Kingdom has a crude birth rate of only 12% per 1,000, where as Ethiopia has a much higher crude birth rate of 43% per 1,000. The less developed a country is, the less education there is, therefore, the birth rate (population increase) goes up. One other factor that leads to the conclusion that Ethiopia is much less developed than the United Kingdom is that the infant mortality rate per 1,000 births is only 5% in the UK, but is 79% in Ethiopia. This statistic shows that there are, first off, many more babies being born in Ethiopia because the birth rate is still higher even though a lot of babies are dying, and that there is less education and, therefore, less advanced doctoring and more disease. It is clear that more babies are being born outside of hospitals in Ethiopia.



1.   Molles, M.C. (2010). Ecology. Concepts and Applications. 5th Ed. NY: McGraw-Hill.

2.   World Population Data Sheet for 2010:


4.   U.S. Census Bureau “International Database”:


Human Domination of Earth’s Ecosystem (Water Pollution):

Millenium Assessment Article (Water Pollution):

EPA- Water Pollution Article:

Project Overview: Final Presentation on Water Pollution

Project Overview: Final Presentation on Water Pollution

Purpose: The purpose of this assignment is to consult the ecology textbook, as well as notes taken in class, in order to choose a topic of interest that will be studied over the next five weeks for a final 10-minute presentation in class.

Topic: I am choosing to study and present a project on water pollution in the world’s waters.

Water Pollution in Relation to Topics Discussed in Class: The topic I’m choosing of water pollution in the world’s waters relates to materials covered in class on a number of levels. We have discussed many topics relating to life under the water and how it is being affected by pollution. We have discussed the depletion of populations, as well as sources of pollution, human interaction, species abundance and diversity, coral reefs, the natural history of aquatic environments, water availability, and even run-off and eutrophication. We have even discussed topics relating to pollution on land in the atmosphere and how that affects the water. In the textbook, we have read and studied chapter 3, Life in Water, as well as chapter 6 on Water Relations. In the future we are going to cover chapter 16 on species abundance and diversity.

Reason for Choosing Water Pollution: I believe that we have discussed pollution relatively thoroughly when it comes to land and atmospheric pollution, but I don’t think we have been as thorough when it comes to the devastating issue of water pollution. I believe it would benefit the class and grasp their attention as I teach them about water pollution and how it is affecting biodiversity under the water. Many species, such as turtles, an umbrella species, are endangered and going extinct. With pollution, populations are being depleted rapidly. It is also interesting to hear how it affects humans with the tiny amount of available clean water left in the world. I plan on also teaching the class exactly what ways the water is being polluted, meaning the sources of the pollution, because it will be interesting for them to learn how they can help make a difference or learn how they are currently polluting the water indirectly or directly. I want to discuss what areas of the world are worst and what areas are the cleanest, so the class can put things in perspective and relate the areas being discussed to their homes. I specifically want to use the Pacific Gyre as an example of how bad water pollution really is because I think the visuals will really impact the class. I also plan on teaching them what the Environmental Protection Agency, working with the Clean Water Act, has planned as goals for the near future to express how serious this ecological issue really is. I want to discuss algae blooms because it’s something we have not really covered and would be new and interesting for the class.

Here are two pictures of the North Pacific Gyre, located in the Pacific Ocean:

Summary of Selected Online Source: The online source I chose is the web page on water pollution found on the Environmental Protection Agency’s website. The page begins by explaining how the EPA divides water pollution into two major categories, point and non-point source pollution. The page then continues to explain briefly what each of these sources of pollution are and how the National Pollutant Discharge Elimination System (NPDES), under the Clean Water Act, regulates this pollution. The web page then explains how the EPA works with state governments and other local authorities in towns and counties to monitor pollution levels in the nation’s water systems. The web page then recommends a few other web pages related to water pollution, such as a summary of the Clean Water Act, which would be useful to someone researching this topic of water pollution. Lastly, there is a large section of EPA water pollution subtopics that each have links to articles and other web pages on different subjects related to water pollution with much more detailed overviews. For example, there are links to aquatic ecosystems, drinking water, ground water, storm water, surface water, wastewater, water infrastructures, water pollutions, water pollution control, water pollution effects, water pollution legal aspects, and water quality monitoring.

Credibility of Online Source: This source is one of the most widely known online sources in the Environmental Science world and it is credible because it is a US governmental website, known by the .gov at the end of the web address as stated in the Online Credibility pdf.


1.   Molles, M.C. (2010). Ecology. Concepts and Applications. 5th Ed. NY: McGraw-Hill.

2.   Photos retrieved

3.   Water Pollution retrieved from

What Kind of Consumer Are You?

Part A: What Kind of Consumer Are You?

Part B: The purpose of this assignment is to study the different types of consumers in order to learn how one’s diet, consisting of different amounts of plants and/or animals, impacts the environment.

Part C: EF, meaning ecological footprint, is the measure of a human‘s impact on Earth’s ecosystem in terms of Earth’s ecological capacity to regenerate. Energy and nutrients flow from producers to consumers within an ecosystem and the flow of nutrients equals the flow of energy. More specifically, nutrients and energy flow from producers, plants, to primary consumers, such as mice, to secondary consumers, such as snakes, to tertiary consumers, such as eagles, to decomposers, such as ants and other insects, back to producers. Then, the cycle begins again. This cycle can also be referred to as the Food Chain and it is a sort of natural recycling process.

Part D:

Calories and the Environment

Diet Source of Calories Number of calories Ecologically equivalent calories Total ecologically equivalent calories
100% plant

0% animal







90% plant

10% animal








50% plant

50% animal







0% plant

100% animal









1.   Calculating Calories and Environmental Footprints: For 100% plant, 0% animal, 2,000 calories would be multiplied by 365 days in a year to get 730,000 ecologically equivalent calories if I was a complete vegetarian and consumed only plants. For 90% plant, 10% animal, 3,800 calories would be multiplied by 365 days in a year to get 1,387,000 ecologically equivalent calories. If 50% of my diet was plants and 50% animals, 11,000 calories would be multiplied by 365 days in a year to get 4,014,000 ecologically equivalent calories. Lastly, if I consumed 100% animals and absolutely no plants in my diet, I would multiply 20,000 calories by 365 days of the year to get 7,300,000 ecologically equivalent calories.

2.   Eat Plants, Not Animals: A diet consisting strictly of animal products, so 100% animal, 0% plants, means one is consuming exactly 10 times the amount of ecological equivalent calories than one would if they consumed only plants, so 100% plants, 0% animals. As seen on the chart above, consuming 2,000 calories of plants means one is consuming 2,000 ecologically equivalent calories, where as consuming 2,000 calories of animal’s means one is consuming 20,000 ecologically equivalent calories. If I consumed as little as 10% of my calories from animal sources to make my diet 90% plant, 10% animal, I would consume 1,800 more economically equivalent calories than if I continued to only eat plants.

3.   Where Do You Stand?: I do not eat any meat or eggs, but I do drink milk and eat yogurt, so I think 90% of my diet comes from plants and 10% comes from animal sources, meaning the ecologically equivalent calorie count of my diet is about 1,387,000 ecologically equivalent calories compared to 730,000 ecologically equivalent calories for someone who is a strict vegetarian.

4.   Population Increase=Food Demand Increase: As the world population continues to rise, so does the demand for food supply. There is a lot of pressure being placed on arable land, land that is still able to be farmed, energy, and natural resources, such as water, to provide an adequate supple of food for mankind while preserving earth’s biodiversity end ecosystems. One other big problem the world’s population faces is malnutrition among children who are not getting enough food and nutrients. People in poorer nations are also developing a taste for an American style diet, meaning rich in animal protein and fat, so arable land and fertile soils are disappearing as farmers continue to farm, use pesticides and fertilizers, and house herds of livestock, destroying land over time.

Ursus Maritimus- Thermoregulation in the Arctic World:

Part A

Ursus Maritimus- Thermoregulation in the Arctic World:

Part B

A Glimpse at Polar Bears and Thermoregulation:

1.    Purpose: The purpose of this assignment is to gather information from the textbook, class notes, and online sources about the thermoregulation patterns of a particular species living in extreme temperatures, in this case, polar bears living in the arctic world.

2.    Background Information: Polar Bears, known scientifically as Ursus Maritimus, meaning maritime bear, are the world’s largest land carnivore and most massive bear, although they spend most of their time hunting at sea. Distributed throughout the Arctic Circle and Adjacent landmasses, they can be found in Europe, Asia and North America, more specifically, Denmark, Norway, Russia, Alaska, and Canada. Polar bears are found in the Tundra biome. As Molles (2010) states, “The Arctic Tundra rings the top of the globe…” (p. 36), housing a typically cold and dry climate, where precipitation exceeds evaporation because average annual temperatures are so low. Precipitation in the tundra varies from less than 200 mm to a little over 600 mm annually, so there is very little rainfall or water availability in this region. The polar bear has evolved to occupy a narrow ecological niche, meaning, as Molles (2010) states, “the environmental factors that influence the growth, survival, and reproduction of a species” (p. 203), with many physical characteristics adapted for cold temperatures and for moving and hunting across snow, ice, and open water.

3.    Need for this Animal to Thermoregulate: Organisms have adapted and evolved ways to compensate for changes in environmental temperature by regulating their body temperature, as Molles (2010) mentions, “organisms regulate body temperature by manipulating heat gain and loss” (p. 110). Polar bears are endotherms and homeotherms, organisms that rely on internally derived metabolic heat energy (Hm) to heat their bodies and maintain relatively constant body temperature. Arctic species have impressively broad thermal neutral zones, as Molles (2010) defines, “the range of environmental temperatures over which metabolic rate of a homeothermic animal does not change” (p. 115). In the arctic, temperatures are extremely low, so polar bears must regulate their heat to keep themselves warm. Because polar bears hibernate for several months at a time during the coldest months of the year, they must thermoregulate while sleeping to keep themselves alive and warm enough to survive. They also spend a lot of their time in the freezing water in order to catch seals, the main source of food in their diet, so they must regulate their body temperatures while below the surface of the icy water in order to stay submerged for long periods of time. Polar bears specifically, regulate their body temperatures both physiologically and behaviorally proportional to their level of activity while within the thermo neutral zone.


Part C

Breakdown of Thermoregulation by Polar Bears:

1.    Polar bears, being endotherms, manipulate heat exchange with the environment using the same anatomical and behavior tricks used by other organisms, so K. Schmidt-Nielsen’s equation for balancing heat gain and loss that we discussed in class and read about in the textbook (p. 115) still applies (Hs = Hm +/- Hcd +/- Hcv +/- Hr – He). However, where it differs for polar bears, and endotherms in general, is in the relative importance of the terms. Endotherms rely much more on metabolic heat, Hm, to maintain constant body temperature. For polar bears, when temperatures are within the thermal neutral zone of an inactive endothermic animal, its metabolic rate stays stead at resting metabolism, but if the temperature falls below or rises above the thermal neutral zone, an endotherm’s metabolic rate will rapidly increase to two or three times resting metabolism.

2.    Polar bears, like other mammals, start shivering at low temperatures, which generates heat by muscle contractions in order to stay warm. They also, like humans, release hormones that increase their metabolic rate, the rate at which they metabolize their energy stores, which are mainly fats. By increasing the metabolic rate, the rate at which they generate metabolic heat increases as well. In hot temperatures, in order to stay cool, polar bears’ heart rate and blood flow to the skin increase, which transports heat from the center of the body to the outer layers of skin, where sweating occurs to unload heat to the external environment.

3.    It is highly important for polar bears to keep their body temperatures stable because they are dealing with extremely low temperatures. As arctic endotherms, they can deal with a very broad thermal neutral zones and can tolerate environmental temperatures down to -30 degrees C without showing any increase in metabolic rate, however with global temperatures on the rise and polar ice caps melting, this arctic species is threatened by extreme environmental changes. They are beginning to have to regulate their body temperatures to adjust to warmer temperatures that they are not necessarily used to or comfortable with. Also, since the ice caps are melting, polar bears have to spend much more time in the water under freezing temperatures, so they have to be able to thermoregulate consistently in order to maintain stable body temperatures to hunt and perform successfully to survive.

Part D




3.    Molles, M.C. (2010). Ecology. Concepts and Applications. 5th Ed. NY: McGraw-Hill.



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