Download ECOLOGICAL NICHE

CHAPTER 7: Community Ecology Concepts
Directions: You are to answer all of these questions, as you are responsible for the information these
questions address. Most of this information is straight-forward and has already been discussed in your
biology course. I strongly urge you to read the section first and then answer the questions.
We will go over any questions you have as a class. Otherwise, it is expected that you understand the
information for the next unit test.
1. COMMUNITY STRUCTURE & SPECIES DIVERSITY
1. Remind yourself what a community is. 
2. Distinguish between conditions and resources.
3. What is a niche?
4. What is the difference between a fundamental niche and a realized niche? (page 89)
5. What role do niches play in environmental science?
6. What are the implications of being a generalist species? (Think of impacts on ecosystem, ways
in which ecosystem supports that organism) (pages 89 – 90)
7. What are the implications of being a specialist species? (Think of impacts on ecosystem,
ways in which ecosystem supports that organism) (pages 89 – 90)
8. Are endangered species usually generalist or specialist species? Provide examples of
endangered species in the United States. (pages 89 – 90)
2. TYPES OF SPECIES
9. What is a native species and what is its role in an ecosystem? Provide examples (you will need
to include the habitat. You should know a few native species our region of the country/state.)
10. What is an introduced species and what is its role in an ecosystem?
a. Which conditions in an ecosystem support these species?
b. Provide examples (you will need to include the habitat. You should know a few
examples in our region of the country/state.)
11. How are introduced species different from invasive species?
a. Which conditions in an ecosystem support these species?
b. Provide examples of invasive species (and include the habitat they are impacting),
especially in Mass.
12. What is an indicator species and what is its role in an ecosystem?
a. Which conditions in an ecosystem support these species?
b. Provide examples (you will need to include the habitat. You should know a few
examples in our region of the country/state.)
c. Why are amphibian populations declining?
13. What is a keystone species and what is its role in an ecosystem?
a. Which conditions in an ecosystem support these species?
b. Provide examples (you will need to include the habitat. You should know a few
examples in our region of the country/state.)
14. What are foundation species and what is its role in an ecosystem?
a. Which conditions in an ecosystem support these species?
b. Provide examples (you will need to include the habitat. You should know a few
examples in our region of the country/state.)
3. SPECIES INTERACTIONS
15. What are the five basic types of interactions among species?
16. What is the difference between interspecific competition and intraspecific competition?
17. Why do species compete with other species?
18. What are the two types of competition?
a. Provide examples.
b. Draw graphical representations of both types.
19. What role does competitive exclusion play in competition?
20. What are ways species have reduced competition? Provide examples.
21. What are ways species have avoided competition? Provide examples.
22. What are examples of predators? (They should be varied!) What are the adaptations these
organisms have to be (successful) predators?
23. Explain the role of feedback, using specific examples, in predation.
24. What are benefits of predation for the predator population?
25. What are benefits of predation for the prey population? What are adaptations some prey have
in order to survive predators?
4. SPECIES INTERACTIONS – SYMBIOTIC RELATIONSHIPS
26. What is symbiosis? Distinguish between symbiosis and parasitism, mutualism and
commensalism.
27. What are examples of parasites and which organism(s) are directly affected?
28. What are roles (be specific to the examples you provided) of parasites in an ecosystem?
29. What are examples of mutualism?
30. Explain how your examples of mutualism play a role in an ecosystem. (Think about how both
organism in the relationship are affected and who their relationship indirectly impacts the
ecosystem.)
31. Explain and provide examples of commensalism.
5. ECOSYSTEM STRUCTURE AND ECOLOGOCIAL SUCCESSION
32. How are primary (ecological) succession and secondary (ecological) succession different?
33. What conditions cause primary succession?
34. Which organisms play an integral role in succession?
a. Discuss the categories of organisms, from pioneer organisms to those in a climax
community.
b. Provide examples of organisms in each category.
35. Which factors determine the components of a climax community?
36. Which conditions cause secondary succession?
37. What are the roles of facilitation, inhibition and tolerance in ecological succession?
38. What role does fire play in succession? (Make strong connections to biomes that rely and do
not rely on fire.)
39. How do monocultures relate to ecological succession?
40. For each of the following unfavorable changes, explain why they are either catastrophic,
gradual or both.
a. Soil erosion
b. Urbanization or urban sprawl
c. Climatic changes
d. Introduction of exotic species
6. ECOLOGICAL STABILITY & SUSTAINABILITY
41. What are the differing viewpoints on the definition of “stability?”
42. What are the roles of persistence (inertia), constancy and resilience in ecosystems?
43. What are the benefits of high levels of biodiversity?
44. What is the role of NPP in ecosystem sustainability?
45. What is the theory of island biogeography? (refer to page 146) Which factors affect the species
equilibrium?
46. How does the American Alligator illustrate the main points of this chapter?
7. CONNECTING IDEAS
For each section, consider and then explain how previously discussed ecological principles (from Ch 3
& 5) relate. Some ideas: energy flow, law of tolerance, energy efficiency, NPP, food webs, nutrient
cycling, K-strategists, carrying capacity. You do NOT need to discuss everything, but this is a great
opportunity to bounce your ideas off of classmates.