1. Population dynamics Births Deaths Births and immigration
add individuals to
a population.
Deaths and emigration
remove individuals
from a population.
Figure 53.3
Immigration
Emigration

2. Patterns of dispersion within a population’s geographic range
(a) Clumped
(b) Uniform
Figure 53.4 Patterns of dispersion within a population’s geographic range
(c) Random

3. Survivorship curves for squirrels shows relatively constant death rate
1,000
100
Number of survivors (log scale)
Females 10
Males
Figure 53.5 Survivorship curves for male and female Belding’s ground squirrels 1 2 4 6 8 10
Age (years)

4. Survivorship Curves Number of survivors (log scale) 1,000 I 100 II 10
Figure 53.6 Idealized survivorship curves: Types I, II, and III
III 1 50
100
Percentage of maximum life span

5. Variation in the size of seed crops in plants
(a) Dandelion
Figure 53.9
(b) Coconut palm

6. 2,000 = 1.0N 1,500 = 0.5N Population size (N) 1,000 500 5 10 15
Exponential Growth Model
2,000 dN =
1.0N dt
1,500 dN =
0.5N dt
Population size (N)
1,000
500
Figure Population growth predicted by the exponential model 5 10 15
Number of generations

7. The J-shaped curve of exponential growth characterizes some rebounding populations
8,000
6,000
Elephant population
4,000
2,000
Figure Exponential growth in the African elephant population of Kruger National Park, South Africa
1900
1920
1940
1960
1980
Year

8. Logistic Growth model Exponential growth 2,000 = 1.0N 1,500 K = 1,500dN =
1.0N dt
1,500
K = 1,500
Population size (N)
Logistic growth
1,000 dN
1,500 – N =
1.0N dt
1,500
Figure Population growth predicted by the logistic model
500 5 10 15
Number of generations

9. The growth of laboratory populations fits an S-shaped curve which hovers around the Carrying Capacity of the area.
1,000
180
150
800
120
Number of Paramecium/mL
600
Number of Daphnia/50 mL 90
400 60
200 30
Figure How well do these populations fit the logistic growth model? 5 10 15 20 40 60 80
100
120
140
160
Time (days)
Time (days)
(a) A Paramecium population in the lab
(b) A Daphnia population in the lab

10. Percentage of juveniles producing lambs
Decreased reproduction at high population densities
100 80 60
Percentage of juveniles producing lambs 40
Figure 53.16 20
200
300
400
500
600
Population size

11. Territoriality (a) Cheetah marking its territory (b) Gannets
Figure 53.17
(b) Gannets

12. 50 2,500 Wolves Moose 40 2,000 30 1,500 Number of wolves
Changes in predation pressure can drive population fluctuations 50
2,500
Wolves
Moose 40
2,000 30
1,500
Number of wolves
Number of moose 20
1,000 10
500
Figure Fluctuations in moose and wolf populations on Isle Royale, 1959–2006
1955
1965
1975
1985
1995
2005
Year

13. Number of hares (thousands) Number of lynx (thousands)
Snowshoe hare
160
120 9
Figure Population cycles in the snowshoe hare and lynx
Lynx
Number of hares
(thousands)
Number of lynx
(thousands) 80 6 40 3
1850
1875
1900
1925
Year

14. Human population growth7 6 5 4
Human population (billions) 3 2
The Plague
Figure Human population growth (data as of 2006) 1
8000
B.C.E.
4000
B.C.E.
3000
B.C.E.
2000
B.C.E.
1000
B.C.E.
1000
C.E.
2000
C.E.

15. Age-structure pyramids for the human population of three countries
Rapid growth
Slow growth
No growth
Afghanistan
United States
Italy
Male
Female
Age
Male
Female
Age
Male
Female
85+
85+
80–84
80–84
75–79
75–79
70–74
70–74
65–69
65–69
60–64
60–64
55–59
55–59
50–54
50–54
45–49
45–49
40–44
40–44
35–39
35–39
30–34
30–34
25–29
25–29
20–24
20–24
Figure Age-structure pyramids for the human population of three countries (data as of 2005)
15–19
15–19
10–14
10–14
5–9
5–9
0–4
0–4
10  8 6 4 2 2 4 6 8
10  8 6 4 2 2 4 6 8 8 6 4 2 2 4 6 8
Percent of population
Percent of population
Percent of population

16. K = carrying capacity Population size (N) dN K – N = rmax N dt K
Review: Population Growth Curve
K = carrying capacity
Population size (N) dN
K – N =
rmax N dt K
Number of generations

17. You should now be able to:
Define and distinguish between the following sets of terms: density and dispersion; clumped dispersion, uniform dispersion, and random dispersion; life table and reproductive table; Type I, Type II, and Type III survivorship curves; semelparity and iteroparity; r-selected populations and K-selected populations.
Explain how ecologists may estimate the density of a species.

18. Explain how limited resources and trade-offs may affect life histories.
Compare the exponential and logistic models of population growth.
Explain how density-dependent and density-independent factors may affect population growth.
Explain how biotic and abiotic factors may work together to control a population’s growth.