Population Models

Population is a complex issue that involves cultural norms, consumption patterns, and constant change.  By visiting the following sites you will model different factors of population growth, by comparing it to other species, analyzing resource use, and calculating your own impact.  Visit each website, and answer the questions that follow. (You may need to search around a bit.)
World Population Balance: http://www.worldpopulationbalance.org/content/earth-clock

1. How many years of oil do they expect we have? (Show your work.)

14216 days/ 365 days a year= 38.94 years of oil left

1. Click on “Understanding Population Growth” on the left.

1. Relate the bacteria in the bottle demonstration to human population growth.

each person having two children will double the population, their children having 2 children will quadruple, and so on

1. Record the formula for calculating doubling time: _70/% growth____________________
2. What is this called?  ___________________the rule of 70_____________

1. India’s Natural Increase Rate is 1.9. How long will it take them to double their population if that rate continues?

70/1.9=36.8years

1. How many years will it take for the global population to double with a NIR of 1.09?

70/1.09=64.2

1. How do the authors see population and consumption related?

The more population, the more people there are to consume, more population equals more consumption

NOT MEETING	Meets (4)	EXCEEDS (5)
SOME PART OF THE MEETS REQUIREMENTS IS MISSING, PLEASE CORRECT AND TURN IN BY NEXT CLASS.	Answers are complete and show understanding of population growth and appropriate vocabulary.	… AND explanations are correct and discussion of limitations is complete and accurate.

---

Global Footprint Network: http://www.footprintnetwork.org/en/index.php/GFN/page/basics_introduction/
Footprints show the area of land or energy resources needed to provide a population with resources and assimilate waste.  It can provide quantitative assessment of a population’s impact.  An approximate formula for footprint is the sum of the two formulas below, multiplied by total population.

1. What limitations do you see with the above formulas?  (What is missing?)

Damage to the environment
Visit the link for the Global Footprint Network

1. How many earths would be needed if the global population led an American lifestyle?

five Earths

1. Define biocapacity?

Capacity of ecosystems to pruduce useful biological materials and to absorb CO2 generated by humans, using current management schemes and extraction technologies

1. Calculate your footprint. How many earths do you require?  _________________

5.2 earths

2. What activities contributed most to your impact (Think beyond the category headings)?

MEAT!!!!!! and electricity usage

1. Compare the national footprints for a MEDC and a LEDC.  Highlight the major reasons and differences behind the figure.

   	MEDC	LEDC
   Country Name	Japan	Uganda
   Graphic	Bottom of Post	Bottom of Post
   Reasons/ differences	The Japanese have enough money per person to drive, buy things and use electrical devices, causing much more emissions	The Ugandans are poorer and can’t afford to drive, use electrical devices, and buy new technology. There is also less technology there causing Ugandans to do things without causing emissions

   1. Conclusion: You have already been introduced to a few population models, including Erlich’s I=PAT, sex/age pyramids from different countries, and the consumption models.
   1. Which model do you find the most helpful in explaining how populations grow?
   
   I find the Demographic Transitions model the most helpful. It shows how country’s populations change over the course of their devolpment
   2. Which model do you find most helpful in explaining the impact of populations?  
   
   Erlich’s model: It shows how each person uses technology and money, multiplying their effects
   3. Pick any model you have studied and summarize its strengths and weaknesses.
   
   Demographic Transitions model: Strength- shows hows medicine and technology affect birth and death rates. Weakness- Doesn’t take cultural practices and beliefs in account, or immigration
   4. Give three reasons why estimating our carrying capacity is difficult.
   
   Humans change their carrying capacity every time we develop new agricultural or efficient technologies. Carrying Capacity can change every day