1.  What is a community?

2.  How do we describe communities?

3.  How is species diversity different from species composition?

4.  The Simpson’s Diversity Index measure the ________________ of a habitat. Higher SDI values mean the community is _____________ diverse.

5.  Competition can occur _______________  or   _______________  species

6.  Interactions between organisms can be _______________,  ______________  or ____________

7.  Describe two examples of positive interactions between species.

8.  Describe two examples of negative interactions between species.

9.  Describe one example of a neutral interaction between species.

10.  Why is the interaction between shelf fungi and trees considered negative?   What positive effects on the community could it have?

11.  How are increases in prey and predator populations related?

12.  What is a trophic cascade?

13.  What is niche partitioning?

14.  STOP the video at 13:10. Which stream types had a statistically lower macroscopic invertebrate species diversity than the seasonal streams?

1.  More diverse ecosystems are ______________ adaptable to changes in the environment.

2.  Diversity of species in ecosystems may influence the _____________ of the ecosystem

3.  Ecosystems can be stabilized with more ________________

4.  Abiotic factors help maintain ____________. Give two examples.

5.  Give two examples of how biotic factors help maintain diversity.

6.  Dominant predators help keep populations __________  ________________

7.  What is a keystone species? Give an example.

8.  Overpopulation of prey species can ______________ resources.

9.  How is the African elephant a keystone species? (Give at least three examples)

10.  STOP the video at 8:08 Predict the change in ground flora of canopy trees if they were artificially planted immediately after the field was abandoned.

1.  Evolution is _____________ in a population over time.

2.  What is an adaptation? What causes adaptations to arise?

3.  List three possible results of increases in the frequency of adaptions.

4.  What is an invasive species? Why do they often outcompete other native organisms?

5.  Human activity ________________ change on local and global levels.

6.  List at least four examples of human impacts on ecosystems.

7.  What are some geological or meteorological events that can change ecosystems?

8.  How do these events accelerate evolution?

9. STOP the video at 12:15. What (if any) was the effect of the introduction of species C on the ecosystem?