The Population Factor
 

             

      In the last 35 years, the human population has nearly doubled from 3 billionto 5.7 billion. At the current rate of growth – 95 million people each year – our population will triple by year 2010. What does this exploding population mean to all the animals?  Let’s find out!

 

     Look at the information in chart # 1 and chart # 2. What connection do you see between the amount of trash generated, the increase in the amount of urban (city) land, and the rising population?

 

   Next, look at chart # 3. (This is an approximate number of animals that have become extinct because there is no way to know how many species became extinct in our earlier history.) What connection do you see between the population rise and the increasing number of extinct animals?

 

     Now compare charts # 4 and # 5. Your challenge is to combine the information into one graph. Plot a line to indicate the world population growth. On top of this line graph, draw bar graphs, at  50-year intervals, to show the number birds and mammals that became extinct during these periods. What relationship do you see between these numbers? Graph paper to help you get started .

 

 

    Once you have analyzed all this information on these charts, what conclusions have you reached? What effect is the increase in population having on animals??


 

 
 


#1 - Average Amount of Trash Generated in U.S. (in lbs./person/day)

 

1960

1970

1980

1990

1995

2.7

3.3

3.7

4.3

4.5



 
 
 

#2 - Approximate Number of Acres Of Urban Land in U.S. (in Millions)

1960

1970

1980

1990

1995

25.5

34.6

47.3

59.7

60.2

 

#3 - Number of Vertebrates that Became Extinct in U.S. and Canada

Date

Fish

Birds

Herps

Mammals

1700 - 1799

0

0

0

2

1800 - 1899

0

19

2

4

1900 - Present

24

17

2

27


 

#4 - Estimates of World Population (in Millions)

1600

1650

1700

1750

1800

1850

1900

1950

2000

470

550

610

760

950

1210

1630

2520

6200


 
 

#5 - Number of Birds and Mammals that Became Extinct Worldwide

Date 

Birds

Mammals

1600 - 1649

3

2

1650 - 1699

6

3

1700 - 1749

4

3

1750 - 1799

4

8

1800 - 1849

22

5

1850 - 1899

48

22

1900 - 1949

65

59

1950 - 2002

?

?




Information for this page came from "Home Is Where the Habitat Is" published by the National Wildlife Federation as part of the 1995 Wildlife Week activities.

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