1. Ecology
AP Biology

2. Ecology
Scientific study of the interactions between organisms and their environment

3. Levels of Study
Organism
Individual
1 turtle

4. Levels of Study Population
Individuals of the same species living in the same area
All the turtles of the same species

5. Levels of Study Community All the organisms living in an area
All the turtles, plants, insects, algae, bacteria

6. Levels of Study Ecosystem
All the organisms and all the abiotic factors
All the organisms & the soil, water, gases, minerals

7. Levels of Study Biosphere
All the organisms & all the abiotic factors on Earth
Earth

8. Complete Question 1
Biosphere
Community
Ecosystem
Organism
Population

9. Abiotic Factors Nonliving Temperature Climate Soil type Rainfall Gases
Minerals

10. Biotic Factors Living Predators Parasites Herbivores Carnivores
Decomposers

11. Complete Question 2
A = abiotic
B = biotic

12. Biomes
Tropical rainforest
Tall trees
High temperature
Heavy rainfall

13. Biomes Savannas Tropical Grasslands Scattered trees High temperature
Less rainfall than tropical rain forest

14. Biomes Temperate grasslands Grasses Seasonal droughts Occasional fires
Lower temperature & less rainfall than savannas

15. Biomes Deciduous forests Deciduous trees Oak, maple Warm summers
Cold winters
Moderate rainfall

16. Biomes Taiga Coniferous forests Pines & firs Cold winters
Heavy snowfall

17. Biomes Tundra Grasses & sedges Very cold winters Permafrost High winds
Little rain

18. Answer Qs 3, 4 and 5

19. Population Ecology
Refer to written notes as you go through the slides

20. Population Definition: Group of individuals: Of same species
Living in same area
Using the same resources
Responding to same stimuli

21. Population Characteristics
Density
Number of individuals per unit area or volume

22. Population Characteristics
Dispersal Patterns
Spacing between individuals
Clumped
Uniform
Random

23. Population Characteristics
Dispersal Patterns
Clumped

24. Population Characteristics
Dispersal Patterns
Uniform

25. Population Characteristics
Dispersal Patterns
Random (ferns)

26. Population Characteristics
Demographics
Study of vital statistics
Age structure
Groupings by age
Graphed
Sex ratio
% of females compared to males

27. Analyze the following graphs
Determine what is causing the various demographic trends in each country

28. Population Characteristics

29. Survivorship Curves
Graph of # of survivors vs. relative age

30. Survivorship Curves
Type I
Most survive to middle age
Humans

31. Survivorship Curves Type II Likelihood of death same at any age
Squirrel

32. Survivorship Curves
Type III
Most die young
Oyster

33. Limiting Factors – add to notes at bottom of page 2
Prevent population from reaching biotic potential
Types
Density dependent
Density independent

34. Limiting Factors Density dependent
Effect becomes more intense with increased density
Examples
Parasites & diseases
Competition for resources
Toxic effect of waste products
Predation

35. Limiting Factors Density independent Occur independently of density
Examples:
Natural disasters
Climate extremes

36. Population Growth Models
Exponential Growth
Change in # of individuals (N) over time (t) is equal to the growth rate (r) times the number of individuals (N)

37. Population Growth Models
Exponential Growth
J-shaped curve

38. Population Growth Models
Logistic Growth
When limiting factors restrict size of population to carrying capacity
Carrying capacity (K) = max. # of individuals of a population that can be sustained by the habitat

39. Population Growth Models
Logistic Growth
Sigmoid (S) shaped curve

40. Add the following 2 slides to notes then complete population ecology questions

41. Life-History Strategies
r-selected species
Exhibit rapid growth (J-curve)
Examples – grasses, insects
Characterized by opportunistic species
Quickly invade habitat
Quickly reproduce
Then die
Produce many offspring that are small, mature quickly, require little parental care

42. Life-History Strategies
k-selected species
Population size remains relatively constant
Example - humans
Produce small number of relatively large offspring that require extensive parental care
Reproduction occurs repeatedly during lifetime

43. Do the population questions!

44. Community Ecology Defintion
An assemblage of populations interacting with one another within the same environment
Use the following slides as reference for question 2

45. Community Interactions
Interspecific Competition
Competition between different species
When 2 species compete for same resources one will be more successful
To survive, the less successful species
Must use slightly different resources
Must use resources during different time of day

46. Community Interactions
Predation
Any animal that totally or partly consumes a plant or animal
True predator kills and eats another animal
Parasite lives in and off a host
Herbivore is an animal that eats plants

47. Community Interactions
Symbiosis
Two species that live together in close contact
Types
Mutualism
Commensalism
Parasitism

48. Community Interactions
Mutualism
Both species benefit from relationship
Examples
Bacteria in root nodules
Lichens – algae & fungus living together

49. Community Interactions
Commensalism
One species benefits while the other is neither harmed nor helped
Examples
Birds building nests in trees
Egrets that eat insects around cattle

50. Community Interactions
Parasitism
One species benefits while the other is harmed
Examples
Tapeworm inside animal
Ticks on dog

51. Ecological Succession
Def- species replacements in a community following a disturbance
Primary – occurs in areas where there is no soil formation (volcanic eruption, glacial retreat)
Secondary – area where soil is present (after a fire, farmland)

52. Detroit

53. Climax Community
F.E. Clements – succession in a particular area will always yield the same type of community – this community is called the Climax Community

54. Pioneer species – the first species to begin secondary succession (plants)

55. Complete questions 3,4 and 5
Gift- here are the answers for 6
1-6 are C
7-8 are D
9 is E
10-11 D
12 E
13 B
14 E
15-18 are B

56. Complete questions 7,8
Gift: Answers for Q 9 B F A D E

57. Ecosystems
Use the summary notes and the following slides to complete the questions on ecosystems

58. Ecosystems – Trophic Levels
Primary producers
Plants
Photosynthetic bacteria
Algae

59. Ecosystems – Trophic Levels
Primary consumers
Herbivores
Eat producers

60. Ecosystems – Trophic Levels
Secondary consumers
Carnivores
Eat primary consumers (herbivores)

61. Ecosystems – Trophic Levels
Tertiary consumers
Secondary carnivores
Eat secondary consumers

62. Ecosystems – Pyramids Pyramid of numbers Most = producers
Least = top level consumers

63. Ecosystems – Pyramids Pyramid of energy Most = producers
Least = top level consumers

64. Ecosystems – Pyramids 10% rule
Only 10% of energy available at each trophic level is converted into new biomass at the next level

65. Ecosystems – Food Chain

66. Ecosystems – Food Web

67. Nitrogen Cycle

68. Water Cycle

69. Carbon Cycle

70. Human Impact Greenhouse effect Ozone depletion Acid rain Deforestation
Pollution
Species extinction

71. ECOLOGY MATH
Population density
= # of members/unit of area

72. ECOLOGY MATH 2) Growth rate (per capita)
= change in number of members/time
r = dN/dt

73. ECOLOGY MATH 3) ZPG = Zero Population Growth birth rate = death rate

74. ECOLOGY MATH 4) Change in population at any one instant dN/dt = rN
Ex 1. A population of 500 experiences 55 births and 5 deaths during a one year period. What was the reproductive rate during this year?

75. ECOLOGY MATH
Ex. 1 A population of 500 experiences 55 births and 5 deaths during a one year period. What was the reproductive rate during this year?
Ans. dN/dt =rN
50/1 = r(500) = .1 or 10%

76. ECOLOGY MATH 5) Intrinsic Rate of Increase (rmax)
-Fastest rate of growth possible
-Pop. Reproducing w/out limits
-Resources abundant
dN/dt= rmaxN

77. ECOLOGY MATH dN/dt= rmaxN
Ex. 2 A population of bacteria with a rmax= .7 per day has a current population of 15,000 cells. How many bacteria will exist in 15 days if resources remain readily available?

78. ECOLOGY MATH
dN/dt= rmaxN
dN/15 = .7(15,000)
N = 157,500 cells

79. ECOLOGY MATH Logistical growth model
- availability of resources limits growth
- carry capacity (K) – max # of individuals of a pop. Supported
dN/dt = rmaxN (K-N/K)

80. ECOLOGY MATH Logistical growth model dN/dt = rmaxN (K-N/K)
Note: As N = K then r = zero
Ex 3. K is estimated at 500, the population size is currently 400 and r is What is the per capita growth rate?

81. ECOLOGY MATH Logistical growth model dN/dt = rmaxN (K-N/K
What does this actually mean?
.8 births per year

82. ECOLOGY MATH Logistical growth model dN/dt = rmaxN (K-N/K
What does this actually mean?
.8 births per year