Community Ecology Study Guide for the Final Exam

Transcription

1 Bioe 147/247 Community Ecology Study Guide for the Final Exam Note: Examples are arranged by topic, and include lectures and all reading assignments. I have focused on those examples emphasized in lectures or readings. The exam will focus on the second half of the course (beginning with herbivory). But because we emphasize synthesis, it will have general concepts (and examples that we repeated) for the entire course. It will probably be a bit longer than the mid-term, with one more short answer question. So you will hopefully be done after 1.5 hours. Note: if you do not find an example in my lectures/supplements, then it is from the reading!! REMEMBER: READ THE INSTRUCTIONS. if we say do 6 of 10 and you answer more than 6, we will only grade the first six that we read. Facilitation Bull s horn Acacia/ants Corals/zooxanthellae Grasses/Fungal endophytes (=endophytic fungi) Mycorrhizae (= mycorrhizal fungi) Orchids/wasps Yucca/moths Also from herbivory lecture: buttercups/grasses seaweeds/fish Community genetics Cottonwoods (Populus) & interactions Marine snails (Nucella)/Mussels (Mytilus) Piñon Pine & interactions White-tailed deer/meningeal worms/moose, etc. Flour beetles Alewives/zooplankton Top-down/bottom-up Coastal CA upwelling Open ocean Cougar Light/algae/grazers/predators Sea otters/orca/urchins/kelp Wolves Bass/minnows/algae Piper/herbivores/predators Missing age-classes (cottonwoods) Mesopredators predators (fox, coyote) Atlantic cod system Interaction strengths Intertidal birds/invertebrates Ythan estuary (Wading birds, flounder, eiders) Pisaster/intertidal effects Diversity/Stability/Disturbance Coral reefs Lobsters/whelks Prairies/grasslands (3 diff examples) Tropical rain forests Ugandan Ironwood rainforest Seeds/spores/diapausing eggs Plankton Reef fish Intertidal algae (greens/reds) (+ examples in other topics that fit here, too) Succession Glacier Bay (Epilobium/Dryas/Alder/spruce) Intertidal algae (greens, reds, Ulva, Gigartina/Mastocarpus) Tropical rain forests (general) Old fields (+ ex from other topics) Climate change Pacifical decadal oscillation (PDO) Eastern deciduous forests Oak/Chestnut Pine/Spruce Amazon rain forest sardines/anchovies Scales of climate change (in Pleistocene & Holocene) Butterflies El Niño

2 Islands Gulf of California Post glacial Little Ice Age Glacial cycles Paleocommunities Trends of families, genera w time Geological periods (esp. Permian, Cretaceous, Pleistocene, Holocene, Quaternary) Dinosaurs (+ others) Plant/insect interactions Megafauna Gastropods Crushing predators Drilling predators 3 major extinctions details as given in lecture & community consequences Landscapes Caribbean birds Gall wasps MPAs Islands Gulf of CA Forests (Harvard Forest/Wisconsin) Hedgerows Lobsters/sea urchins/kelp Fish/dragonflies/pollinators/plants Urchins/lobsters Ecosystems Deforestation experiments Bush lupine/exotic plants Ceanothus Grasslands Salmon Productivity in different habitats (know rough global patterns) in Carpenter s chapter, focus on N and pages 129, 131 (fig.), , Human Impacts/ecosystems N-deposition Mississippi River/Gulf of Mexico Grasslands Invasive Species Tussock vegetation San Francisco Bay Grasslands Human impacts/interactions Anthropogenic biosphere Yellowstone fires Acorns/ticks/etc Caribbean reefs Short-Answers: Thought questions for the exam (most are 10 pts each). Notes: These pages cover only the short essay (or short answer) questions and the major graphs. Some of them cover topics that we may not get to in lecture, but those should be obvious. For all, give specific examples, graphs or diagrams as needed. Most of these questions go beyond repeating what was in lectures or readings, and hopefully will help you think about the class in a broad context. We have covered an enormous amount of material in this course even in just the second half. Below are the main questions that you should be able to answer (with some help from earlier concepts). NOTE: you should be able to answer ALL of these questions from class material. To help you focus and get give better answers on the exam, I have flagged () 12 of these. About 6 of them will definitely be on the exam.(none of those without an ) 1. Using one example from this course, explain in depth how and why mutualistic interactions are often examples of reciprocal exploitation rather than true cooperation? 2. Explain community-level consequences of extended phenotypes in these systems: a) deer and moose; b) Piñon pines and moths; c) cottonwoods and beavers; d) flour beetles; e) alewives and plankton 3.Why may plant or algal production in two communities (of the same type and in the same environment) be very different even though resource inputs are equal?

3 4. Why might communities dominated by mesopredators differ from those dominated by an apex predator? Give an example. 5. Explain how top-down and bottom-up processes can both affect the same system. Give examples. 6. Explain why Interaction Strengths or Effect Sizes are not predicted by the amount of energy/carbon flow? 7. It was long assumed that communities with higher S (species richness) are also more stable. a) Name 2 other ways of categorizing species that may also be important. b) Which of these (from your list plus S) are consistent with recent data? c) How does the community-wide distribution of Interaction Strengths affect community stability? d) How does the Intermediate Disturbance Hypothesis fit into this notion of S of stability? 8. As a resource manager, you must plan the intensity and spatial patterning of a disturbance. This can be either a) clear cuts in a forest, or b) zones that permit bottom trawling (= dragging traps) on the sea floor. Choose one of these habitats and indicate how the following processes affect your plan: biotic interactions, succession, island biogeography, community stability (define how you use it), keystone species, trophic cascade, and community genetics. 9. The contexts and complexities of interactions is a major theme of this course using one graph, illustrate how the importance (or intensity) of competition, predation, facilitation and physical stresses may be related to each other. 10. Discuss how contexts become very important for interactions of even the same species. Include in your discussion at least one example of a) keystone species; b) effect size; c) kelp abundance; and d) endophytic fungi. 11. What are the predicted outcomes of a disturbance event at an MSS for the a) classical, b) tolerance, and c) inhibition mechanisms of succession. Explain key points of each mechanism. How would you set up an experiment to test for the mechanisms in your system? Explain how all 3 mechanisms can apply to the same system, using the Glacier Bay example. 12. Why are the lottery and intermediate disturbance models considered non-equilibrium explanations of S? 13. What basic assumptions do equilibrium and non-equilibrium explanations of S make? Contrast/discuss these mechanisms to maintain S. Briefly, name and explain two different mechanisms of each. 14. Relate regional vs. local processes to the concepts of open vs closed communities and how they might affect a) management, b) community stability, c) resource limitation within a community, d) evolution and community genetics, e) succession, or f) survival and growth of young Pacific salmon. 15. Explain how subsidies from one system to another (of the same or different type) affect communities. Give 2 examples. 16. How do past climates affect the structure of current communities and coevolution of species within them? Why do time lags of responses to climate change differ among species and how do time lags affect ecological communities? For time lags explain two examples, at least one of which is from the Davis paper and not covered in lecture. 17. Briefly, compare how communities have changed over geological time to now in terms of number of families, guilds and interactions. How have major extinction events affected these trends? 18. How and why have ecological communities changed since the last glacial retreat? Consider at least three distinct ecological events/situations and their rough timing. 19. a. List 3 of the leading hypotheses that may explain why species can become invasive. b. How are these 3 hypotheses unified by the concept of Niche Opportunities? c. What role does diversity (of the native community) play in invasions under the Niche Opportunities hypothesis?

4 20. Graphically, and then in words, explain the relationship between S of native species and the number of exotic species that can become established. Include large-scale effects and small-scale effects. Give one example at large- and one at small spatial scales. 21. Community-level and ecosystem-level approaches to understanding ecological systems have major differences. Explain why these different approaches may give different explanations for the same pattern and how each might be used to 1) study an ecological question and 2) suggest management options. 22. Give examples of how changes in our understanding of how ecological communities really work can lead to differences in management practices. 23. As a community ecologist, you are being asked to make recommendations about wolf densities near Yellowstone and Isle Royale. Use your knowledge of top-down controls and diversity-stability relationships to discuss types of changes (if any) in community structure/ecosystem functioning if wolf hunting is markedly increased near Yellowstone? Are these effects similar or different to what you might expect if wolves were eliminated from Isle Royale NP? Explain your reasoning. 24. Concepts of spatial and temporal scales are central to understanding patterns and processes in ecology. Give/explain 2 examples from this course where examining the system at different scales led to altered perspectives and predicted outcomes. 25.Distinguish between these pairs of concepts using one or two critical observations or experiments: competition v facilitation (beneficial); facilitation (in succession) v inhibition; closed v open systems; TD v BU; weak v strong IS; alternate state v alternate stable state; resistance v resilience; etc.. Do NOT define the concepts. 26. How might contemporary climate warming affect phenotypes? How might those trait changes affect communities? 27. Describe the cascading evolutionary and ecological consequences of damming streams in Connecticut. How were fishes (multiple species) affected? How was plankton affected? 28. Some people are worried that anthropogenic effects on biotic and abiotic components of environments will lead to novel communities. Should they be? Evaluate this concern given what you know about ecological communities over time and space. In detail, explain one example related to natural systems and one example showing anthropogenic effects. SAMPLE TEST: ESSENTIALLY SAME LENGTH AND FORMAT AS THE MID-TERM: I. (6 or 8 5 pts each (3: definition, 2: example) Define the following (1 short sentence/phrase (NOTE examples from this class ONLY) each) Reciprocal exploitation Extended phenotype Ecosystems Niche opportunities Etc. II. Examples note: we are NOT asking which ONE process is common to some of the examples. Simply one of the processes shown by each of the examples that you select (10 total). (from the first 2 pgs of this handout) Flour beetles Ythan estuary.

5 .. III. KNOW THE IMPORTANT GRAPHS: Short-answer (10 pts each) On the graph below indicate which line shows: 1 a. Local stability 2 b. Global stability c. Describe in words what each line/arrow tells you. #1: #2: d. label the axes

6 MAJOR GRAPHS Know the graphical patterns of the main examples concepts. The graphs below show only the major concepts. Interaction Strengths Alternative States Alternative Stable States comm. 1 comm 1 comm. 2 comm 2

7 Predators (resistant spp)

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9 Landscape Ecology: Ecosystems-level Ecology Human Impacts: Biological invasions N-deposition S N-depositions

10 People and nature (Anthropocene)