The document discusses key facts and trends related to human population dynamics: - Current world population is 6.8 billion people and growing at a rate of 1.15% annually. - Population growth has been exponential in recent centuries, doubling approximately every 61 years at the current growth rate. - More developed countries consume far more resources per capita than less developed countries, though less developed countries account for most population growth. - Factors like education, affluence, and women's empowerment impact birth and growth rates in different regions.

1. HUMAN POPULATION
DYNAMICS

2. See World Population Video
• What do you think? Video
Did you Know?

3. 06_12.JPG

4. How many people are on Earth?
• 6,788,977,211 (6.8 billion)
• How many people are in the U.S.?
– 308 million
• How much is 6.8 billion?
– See next slide for an exercise
Pop Census

5. How long would it take you to put
6.8 billion dots on a piece of paper?
• Take out a piece of paper and pen or pencil.
• Count the number of dots you can put on a piece
of paper in 5 seconds (have a partner time 5 sec).
• Calculate Dots/minute (x12), dots/hour (x60),
dots/day (x24), dots/year (x365).
– 6.8 billion dots divided by dots/year
POP 6800000000
DOTS/5s 26
YEARS 41.47
Note: 77 million
more people
added per year
you were
putting dots

6. How many people are on Earth?
• How much is one billion?
– How long is 7.8 billion seconds?
• 1 billion seconds is 31 years, 8.5
months!
• 6.8 billion = 215 years, 7.5 months!

7. History of Human Pop Growth
• 1804: 1 billion (took a looong time)
• 1927: 2 billion (took 123 years more)
• 1960: 3 billion (33 years)
• 1974: 4 billion (14 years)
• 1987: 5 billion (13 years)
• 1999: 6 billion (12 years)
• ????: 7 billion (? Years)

8. History of Human Pop Growth

9. Population Growth Rates

10. Future of Human Pop Growth?

11. 06_06.JPG

12. Future
of
Human
Pop
Growth
?

13. Population Density

14. Average Annual Rate of Change

15. Current Pop Growth Rate
• 10
• 9
• 8
• 7
• 6
• 5
• 4
• 3
• 2
• 1
• 0
41 people were born
• 18 people died
• = 23 people added to Earth
During this class… 39,244 born;
17,187 died; 22,058 people added
In these 10 seconds…
World Clock

16. Current Pop Growth Rate
• 1.15% annual growth
– What does this mean?
– Use Rule of 70 to determine
Doubling Time

17. Type of Pop Growth
• Exponential Growth: J Curve
– Occurs when pop is growing at a
percent annual growth (versus some
fixed amount).

18. Power of exponential growth:
paper folding example
# Folds Thickness
20
30
40
50
332 feet
64 miles
65,943 miles
67.5 million miles
Using 0.0038” for paper thickness (20 lb test) =
263 sheets/inch.
10 3.9 inches

19. Rule of 70 to determine
Doubling Time
• 70 divided by % Annual Growth =
Doubling Time (i.e., how long it takes
for the population to double)

20. Rule of 70: Example 1
• Example: 10% annual growth rate
• Current population is 1 million
• How long will it take to reach:
– 2 million?
• 70/10 = 7 years
– 8 million?
• 7 X 3 doubles = 21 years

21. Rule of 70: Example 2
• Example: 1.15% annual growth rate
• Answer: 70/1.2 = 61 years for
population to double in size
• So… in 61 years, at this rate, we will
have twice as many people on Earth!

22. Exponential Growth
http://dieoff.org/page80.htm
What
should be
done?

23. Exponential Growth
http://dieoff.org/page80.htm
What
should be
done?

24. Exponential Growth
http://dieoff.org/page80.htm
What
should have
been done?

25. Exponential Growth
What should wildlife
managers do?
Hunt them
Add predators
Move them
Do nothing (let them
starve)

26. Here’s another population
0
1
2
3
4
5
6
7
1800 1850 1900 1950 2000
Year
Population(inbillions)
What did you
say we should
do?

27. Biotic Potential vs.
Environmental
Resistance
• One pair of cats adds up
to (assumes no deaths):
• First yr: 12
• Second yr: 66
• Third yr: 382
• Fourth yr: 2201
• Tenth yr: 80,399,780

28. Carrying Capacity
• MAXIMUM number of individuals an
area can support FOREVER.
• Law: Thou shalt not exceed the
carrying capacity, for long.
– As the caribou found out

29. Carrying Capacity
• What is the carrying capacity for
people on Earth?

30. Cultural Carrying Capacity
• Maximum number of individuals an
area can support forever AT A
GIVEN STANDARD OF LIVING.

31. What determines whether a
population size changes?
• Rate of Increase = (Birth Rate
+Immigration) – (Death Rate + Emigration)
• Age Structure = age and sex proportions in
a population
• Total Fertility Rate = average # of children
a woman has in her lifetime.
• Replacement Level Fertility Rate = average
# of children a couple must have to replace
themselves.
– 2.1 in MDCs and 2.5 in LDCs

33. Fig. 4.8
AGE STRUCTURE

34. TOTAL FERTILITY RATE

35. Factors affecting birth rates
• Education
• Affluence
• Religious/cultural norms
• Role of women in society
• Infant mortality rates
• Availability of birth control

36. • Life Expectancy = how long an individual
is expected to live once they are born.
What determines whether a
population size changes?

37. Table 4.3

38. • Life Expectancy = how long an individual
is expected to live once they are born.
WHAT FACTORS DO YOU THINK
INFLUENCE LIFE EXPECTANCY?
What determines whether a
population size changes?

39. Fig. 4.7

40. Human Population Growth and
the Environment
• Who has a greater impact on the
environment?
– Lesser Developed Countries??
– More Developed Countries??

41. Two Types of Overpopulation
• People Overpopulation
• Consumption Overpopulation
• Who has greater impact on the
environment – Lesser Developed
Countries with 80% of the people or
More Developed Countries using high
percentage of the resources?

44. Fig. 4.4

45. Population Growth Rates

46. 06_04.JPG

47. 06_16.JPG

48. Questions
• How does population growth affect
our world today?
• What will happen in the future if we
do not control population?
• What are the options for controlling
population? Pros and Cons:
– Volunteer vs Forced
• How should we control population?

49. If we could shrink the earth's population to a village
of precisely 100 people,
with all the existing human ratio's remaining the
same, there would be:
• 57 Asians
• 21 Europeans
• 14 from the Western Hemisphere, both N and S
• 8 Africans
• 52 would be female
• 48 would be male
• 70 would be nonwhite
• 30 would be white

50. If we could shrink the earth's population to a village
of precisely 100 people,
with all the existing human ratio's remaining the
same, there would be:
• 70 would be non-Christian
• 30 would be Christian
• 6 people would possess 59% of the entire world's
wealth and
• all 6 would be from the United States

51. If we could shrink the earth's population to a village
of precisely 100 people,
with all the existing human ratio's remaining the
same, there would be:
• 80 would live in substandard housing
• 70 would be unable to read
• 50 would suffer from malnutrition
• 1 would be near death; 1 would be near birth
• 1 (yes only one) would have a college education
• 1 would own a computer

52. • If you woke up this morning
with more health than
illness, you are more
fortunate than the million
who will not survive this
week.

53. If you have never experienced
the danger of battle,
the loneliness of imprisonment,
the agony of torture,
or the pangs of starvation,
you are ahead of 500 million
people in the world.

54. If you have food in the refrigerator,
clothes on your back,
a roof overhead
and a place to sleep,
you are richer than 70% of this world.

55. If you have money in the bank,
in your wallet, and spare
change in a dish someplace,
you are among the top 8% of
the world's wealthy.

56. If you can read this message,
you are more fortunate
than over two billion people in the world
that cannot read at all.
Did you Know?

57. THE FACTS ON CONSUMPTION
• Which world region consumes the most
energy per person?
•Average energy use per person is 9
times greater in more developed than
less developed regions.
•North Americans consume far more
energy than any other region.

58. THE FACTS ON CONSUMPTION
• Which world region consumes the most energy
per person?
In 2005, per capita energy use among
Americans was
•2x that of Europeans
•8x that of Developing Countries