1. Population Dynamics

2. Population change in : Change due to stress Size Density Dispersion
Age distribution
Change due to stress

3. Population change Growth sources: Depends on resource availability
Birth, death, emigration (out), immigration (in)
Depends on resource availability
Density independent controls – anything that reduces size despite population size (natural disasters)
Density dependent controls – reduces size of population but size can influence (disease, predation)

4. Carrying Capacity
Carrying capacity – max population that a habitat can sustain

6. Population Growth Exponential – has few resource limitations
Logistic – slow and steady over time; carrying capacity maintained

8. Population curves: Stable – fluctuates right above and below K
Cyclic – rises and falls in regular intervals
Irruptive – increase drastically and quickly (more rare)

10. Predation and Population Control
Top-down control – Trophic cascade
Bottom-up control –Primary productivity

12. Opportunist or r-selected species
Reproduce early in life
Short generation times
Have many offspring
Short life span
Reproduce rapidly when conditions are favorable

13. Competitor or K-selected species
Reproduce late in life
Have few offspring that are nurtured them to maturity
Do well in competitive conditions

14. Survivorship Curves

15. Influences
List at least one thing that comes to mind with the following words?
Religion
Culture
Industrialized Nation
Developing Nation
How would these factors influence the population size of a country?

16. Survivorship Curves
Shows the number of survivors of each age for a particular species
Three types:
Early loss: typical of r-selected; many die out early in their life (Type III curve)
Constant loss: have fairly constant rate of mortality in all age ranges (Type II curve)
Late loss: typical of K-selected species; lots of energy to assure offspring reach reproductive age (Type I curve)

18. The human population is about 7. 35 billion people
The human population is about 7.35 billion people. In the 1800’s, it finally reached 1 billion. What factors have contributed to this surge in the human population size?

19. Human Population

22. CBR and CDR
CBR (crude birth rate) – number of live births per 1000 people
CDR (crude death rate) – number of deaths per 1000 people
Demographers use CBR and CDR to make predictions about potential population size

23. Fertility Rates
Replacement level fertility – # of children a couple must bear to replace themselves
Total fertility rate – average number of children a woman will have during childbearing years
USA – Italy – 1.4
India – Japan – 1.3
China – 1.55

24. Quality of Life Measure…
Infant mortality rate
Indicates health care capabilities of country

25. Factors Affecting Birth Rates
Are children important to the labor force?
Cost of raising and educating children
Educational and employment opportunities for women
Infant mortality rate
Availability of reliable methods of birth control
If it is available, will people use it?
Religious beliefs, traditions, and cultural norms

26. Factors that Affect Death Rate
Reasons for decline:
Increased food supplies
Better nutrition
Improvements in medicine and public health
As these things increase, so does the life expectancy of a society (average # of years a newborn can be expected to live)

27. Population Age Structure
Histograms show the proportion of the population at each age level
Divided by age and gender
Males – left; females - right
3 categories:
Prereproductive (0-14)
Reproductive (15-44)
Postreproductive (45+)

28. What A Histogram Can Show You
Industialization
Growth rate
War or Disease
Baby boom

29. Type of population growth
Rapid – large section of population is 15-under
Means lots of young people will move into reproductive age
More common in developing countries

30. Rapid Growth

31. Slow – Zero Growth
Population pretty evenly distributed

32. Slow-Zero Growth

33. Negative Growth
Majority of population is in late reproductive to post reproductive age

34. Negative Growth

35. Compare the two histograms
Compare the two histograms. Identify the growth rate and predict the population size in 50 years

36. Demographic Transitions – Moving towards Industry
4 Stages:
Preindustrial :
Little population growth due to harsh conditions
High birth rates and high death rates (close to ZPG)
ZPG – Population size remains steady, no growing
Transitional:
Industrialization begins, health rises, food rises
High birth rates b/c children aren’t dying out, but death rate drops

38. Industrial :
Industrialization is widespread and birth rates begin to drop
Postindustrial:
Reaches ZPG

40. New 5th Stage?
Declining – the population will decline due to death rate being higher than birth rate

42. No Calculator – Calculate the following
/12
2. 60/2.5
3. 48/3.2

43. Calculating % Growth Rate
Formula = CBR-CDR/1000 x 100% OR CBR-CDR/10
In 2000, the world birth rate was 10 births per 1000 people. The world death rate was 12 deaths per 1000 people. Calculate the world % growth rate

44. You Do It
In 1900, the world birth rate was 42 births per 1000 people. The world death rate was 36 deaths per 1000 people. Calculate the world growth rate %.

45. Doubling Time
Amount of time it will take a population to double in size (assuming a constant rate)
Can calculate by growth rate or years
To find years using a rate = 70 / Rate
To find rate using years = 70 / # of years

46. Time Example – A population doubles in 10 years
Time Example – A population doubles in 10 years. What is the growth rate of this population?

47. You Do It
It takes a population 140 years to double in size. What is the growth rate of this population?

48. Growth Rate Example – A population has a growth rate of 2. 0 in 2000
Growth Rate Example – A population has a growth rate of 2.0 in In what year would the population be double its current value?

49. You Do It
A population had a growth rate of 3.5% in In what year would the population be double its current value?

50. Calculating Population Growth Over 1 Year
How a population changes over the course of a year including migration
Formula:
PN = PI + [(B-D)(# of thousands)] + [(I – E) (thousands)]
PN = Population expected for next year
PI = Initial population of area
B = birth rate
D = death rate
I = immigration
E = emigration

51. A suburb of Charlotte has a population of 5,000 people in 2000
A suburb of Charlotte has a population of 5,000 people in The birth rate was measured at 25 per 1000 population while the death rate was measured at 18 per 1000 population per year. Immigration was measured at 10 people per 1000 and emigration was measured at 7 people per Calculate the population size in 2001.

52. A suburb of Charlotte has a population of 10,000 people in 2002
A suburb of Charlotte has a population of 10,000 people in The birth rate was measured at 10 per 1000 population while the death rate was measured at 15 per 1000 population per year. Immigration was measured at 10 people per 1000 and emigration was measured at 15 people per Calculate the population size in 2003.

53. Population Control in China and India
Considered successful because it is made available to everyone and there are economic incentives
India
Birth control is not equally accessible
Growth rate is declining
High infant mortality and early childhood mortality

54. Cutting Growth Population Growth
1994 –Conference on Population and Development - Cairo, Egypt
Goals:
Stabilize 7.8 billion people
Provide universal family planning
Improve health care
Increase access to education
Take steps to eradicate poverty

55. Population Momentum
The natural rate of a country’s population increase

56. Find the growth rate, the population density, which country will double the fastest, and the population size after one year using the growth rate
Top 10 Most Populous Countries in the World:
China - Pakistan
India - Nigeria
USA - Bangladesh
Indonesia - Russia
Brazil - Japan -

57. After you have calculated all countries…
Pick a country from the list. Summarize the information you found about population size, density, etc. Then, explain why you think this country’s population is the size that it is. Also, discuss at least 2 potential issues that the country should be on the lookout for at the current rate of growth…