1. Make observations and come up with explanation

2. Results
When grown alone, both species displayed logistic growth and reached carry capacity (64 for P. caudatum; 105 for P. aurelia).
In mixed culture, two important events observed:
1. neither grew to size observed when grown alone (effect of competition).
2. P. caudatum was driven to extinction = competitive exclusion -- after extinction of P. caudatum, P. aurelia grew to its carrying capacity.

3. Competition: a closer look
Interference~ actual fighting over resources
Exploitative~ consumption or use of similar resources
Competitive Exclusion Principle (Lotka / Volterra)~ 2 species with similar needs for the same limiting resources cannot coexist in the same place √Gause experiment with Parameciums.
2 species competiting for the same resource; one will die

4. d= is basically shorthand for "the change in“
N = total number of organisms making up the population
t = time
rmax=the maximal growth rate in the absence of density effects, namely at low population sizes.
K=carrying capacity
The change in number of organisms over…

5. Density growth and equation breakdown

6. Predation defense Cryptic (camouflage) coloration
Aposematic (warning) coloration
Mimicry~ superficial resemblance to another species √ Batesian~ palatable/ harmless species mimics an unpalatable/ harmful model
√ Mullerian~ 2 or more unpalatable, aposematically colored species resemble each other

7. Competition Adaptations
Character displacement~ sympatric species tend to diverge in those characteristics that overlap
Resource partitioning~ sympatric species consume slightly different foods or use other resources in slightly different ways
Ex: Darwin’s finch beak size on the Galapagos Islands. A body part has mutated over time so that species can eat a different size seed
Ex: Anolis lizard sp. perching sites in the Dominican Republic. All species eat insects but they have a different perch site.

8. The Niche
Ecological niche~ the sum total of an organism’s use of biotic and abiotic resources in its environment; its “ecological role” √ fundamental~ the set of resources a population is theoretically capable of using under ideal conditions √ realized~ the resources a population actually uses
Thus, 2 species cannot coexist in a community if their niches are identical
Ex: Barnacle sp. on the coast of Scotland

9. Close notes and teach
Each member teachs 5 main points from today’s lecture

10. Activity: Deer graph

11. Dispatch
How can species use the same resources without ever seeing each other?
Using a book, compare and contrast primary and secondary session
Pick up a succession paper
Retakes available during office hours

12. Succession
Mt. St. Helens BEFORE 1980
Ecological succession~ transition in species composition over ecological time
Primary~ begun in lifeless area; no soil, perhaps volcanic activity or retreating glacier
Secondary~ an existing community has been cleared by some disturbance that leaves the soil intact
Mt. St. Helens AFTER ERUPTION in1980

13. Glacier Succession Animation

14. Ecosystems and Physical Laws
Energy is conserved
But degraded to heat during ecosystem processes
Nutrients are recycled

15. ACTIVITY Why aren’t there 20 links in a food chain?
Demonstrate the flow of energy between links in the food chain

16. Dispatch What is the format of the Ecology test on Friday?
How will you study for the test?
Give 5 things you know about ENERGY.
Interpret diagram below.
If you finish before timer go to the whiteboard and look at the AP plaque

17. Production Efficiency
When a caterpillar feeds on a plant leaf
Only about one-sixth of the energy in the leaf is used for secondary production
Figure 54.10
Plant material
eaten by caterpillar
Cellular
respiration
Growth (new biomass)
Feces
100 J
33 J
200 J
67 J

18. Energy flows through an ecosystem
Entering as light and exiting as heat
Figure 54.2
Microorganisms
and other
detritivores
Detritus
Primary producers
Primary consumers
Secondary
consumers
Tertiary consumers
Heat
Sun
Key
Chemical cycling
Energy flow

19. Pyramids of Production
This loss of energy with each transfer in a food chain
Can be represented by a pyramid of net production
Figure 54.11
Tertiary
consumers
Secondary
Primary
producers
1,000,000 J of sunlight
10 J
100 J
1,000 J
10,000 J

20. Worldwide agriculture could successfully feed many more people
If humans all fed more efficiently, eating only plant material
Trophic level
Secondary
consumers
Primary
producers
Figure 54.14

21. Where will the oxygen be highest? Why?

22. Dissolved Oxygen Lab 22

23. Water Quality: DO2 23

24. Factors that INCREASE O21) 2) 3) 4) 5)

25. Gross and Net Primary Production
Total primary production in an ecosystem
Is known as that ecosystem’s gross primary production (GPP)
Not all of this production
Is stored as organic material in the growing plants
Net primary production (NPP)
Is equal to GPP minus the energy used by the primary producers for respiration
Only NPP
Is available to consumers

26. NPP=GPP-R Equation Write this in words DESIGN A LAB TO MEASURE NPP
Hint: How does cellular respiration affect O2?

27. The Global Energy Budget
The amount of solar radiation reaching the surface of the Earth
Limits the photosynthetic output of ecosystems
Only a small fraction of solar energy
Actually strikes photosynthetic organisms

28. Different ecosystems vary considerably in their net primary production
And in their contribution to the total NPP on Earth
Lake and stream
Open ocean
Continental shelf
Estuary
Algal beds and reefs
Upwelling zones
Extreme desert, rock, sand, ice
Desert and semidesert scrub
Tropical rain forest
Savanna
Cultivated land
Boreal forest (taiga)
Temperate grassland
Tundra
Tropical seasonal forest
Temperate deciduous forest
Temperate evergreen forest
Swamp and marsh
Woodland and shrubland 10 20 30 40 50 60
500
1,000
1,500
2,000
2,500 5 15 25
Percentage of Earth’s net
primary production
Key
Marine
Freshwater (on continents)
Terrestrial
5.2
0.3
0.1
4.7
3.5
3.3
2.9
2.7
2.4
1.8
1.7
1.6
1.5
1.3
1.0
0.4
125
360
3.0 90
2,200
900
600
800
700
140
1,600
1,200
1,300
250
5.6
1.2
0.9
0.04 22
7.9
9.1
9.6
5.4
0.6
7.1
4.9
3.8
2.3
65.0
24.4
Figure 54.4a–c
Percentage of Earth’s
surface area
(a)
Average net primary
production (g/m2/yr)
(b)
(c)

29. Overall, terrestrial ecosystems
Contribute about two-thirds of global NPP and marine ecosystems about one-third
Figure 54.5
180
120W
60W 0
60E
120E
North Pole
60N
30N
Equator
30S
60S
South Pole