Review Questions Chp 47 (community Interactions)key

Review Questions - Chapter 47 “Community Interactions” (Ignore page references)

1. The type of place where you normally find a maple is its ____habitat______. [p.720]

2.      

List five factors that shape the structure of a biological community. Climate and topography Available foods and resources Adaptations of species in community Species interactions Arrival and disappearance of species Physical disturbances

3. An organism’s __niche________ is the sum of activities and relationships in which it engages to secure and use the resources necessary for its survival and reproduction. [p.720] 4. Contrast the terms fundamental niche and realized niche.  Fundamental niche – Theoretical niche occupied in the absence of any competing species  Realized niche – Niche a species actually occupies  Realized niche is some fraction of the fundamental niche

5. The interaction of a bird’s nest and a tree is known as __commensalism________. [p.720] 6. In forms of ___mutualism_______, each of the participating species reaps benefits from the interaction. [p.720] 7. In ___interspecific_______ competition, disadvantages flow both ways between species. [p.720] 8. ____Predation______ and __parasitism________ are interactions that directly benefit one species and directly hurt the other. [p.720] 9. Commensalism, mutualism, and parasitism are all forms of __symbiosis________, which means "living together." [p.720]

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10. Define and cite an example of obligatory mutualism.  Both species benefit  Many examples in nature  Some mutualisms are obligatory; partners depend upon each other  Example of an obligatory mutualism  Each species of yucca is pollinated only by one species of moth  Moth larvae can grow only in that one species of yucca

11. Define intraspecific competition and interspecific competition

  

Interspecific ­ between species Intraspecific ­ between members of the same species Intraspecific competition is most intense

12. Describe a study that demonstrates laboratory evidence supporting the competitive exclusion concept. When two species compete for identical resources, one will be more successful and will eventually eliminate the other P. caudatum and P. aurelia are raised in the same culture; in a few weeks, the P. caudatum levels are very low or at zero; P. aurelia has out-competed P. caudatum (they can survive in separate cultures).

13. Define a keystone species and cite one example.  A species that can dictate community structure  Removal of a keystone species can cause drastic changes in a community; can increase or decrease diversity

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 Example: Sea otter along the pacific coast dictate C.S for the kelp forest (marine algae ecosystem)

14. Cite one example of resource partitioning. River Otters Avoid Each Other Thus Reducing Intraspecific Competition. They partition the river into family territories.

A predator gets food from other living organisms, its _prey_________. [p.724]

15. Explain the three-level interaction found between lynx, snowshoe hare, and plant populations. Plants provide food for hares which are the prey for lynx. In poor growth years, the hare population is reduced and the effects are felt by the lynx who have less to eat. Cycles of population numbers for both species change of time. The lynx may migrate out of the area and disrupt these cycles. 16. __Parasites________ take up residence in or on other living organisms--their hosts--and feed on specific host tissues for part of the life cycle. [p.724] 17. Many of the adaptations of predators (or parasites) and their victims arose through ___coevolution_______. [p.724] 18. What are the general body locations of ectoparasites (external body surface) and endoparasites (inside body)? [p.725] 19. List the types of organisms classified as microparasites and those classified as macroparasites. Cowbirds are classified as __social parasites________ parasites. [p.725] 20. Be able to discuss advantages and disadvantages of using parasites as biological controls .See page 282 21. Be able to completely define and give examples of the following prey defenses: warning coloration, mimicry, moment-of-truth defenses, and camouflage. See page 283, Commentary.

22. Describe two examples of how predators counter prey defenses with their own marvelous adaptations. Lions use stealth; wolves use pack hunting

23. Define ecological succession.

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The community develops from pioneer species through a series of community stages until a stable (self perpetuating) assemblage appears (climax community).

24. A __climax________ community is a stable, self-perpetuating array of species in equilibrium with one another and their habitat. [p.728] 25. Distinguish between primary and secondary succession. [p.728] 26. By the ___climax_______-__pattern________ model, a community is adapted to a total pattern of environmental factors. [p.728] 27. Describe how fire disturbances positively affect a community of giant sequoias. Fire sweeps through the forest periodically and consumes the underbrush releasing nutrients reducing competition. 28. Distinguish between natural and active restoration Natural is secondary succession while active is planned and executed by humans (faster) 29. Community __instability________ is an outcome of forces that have come into uneasy balance. [p.730] 30. Explain how the introduction of exotic species can be disastrous. List five specific examples of species introductions into the United States that have had adverse results. Exotics tend to out compete native species since the exotics often don’t have predators or parasites introduced with them. Kudzu, rats, German cockroaches, cane toads, fire ants, starlings, privet, etc 31. List three factors that underlie the existing patterns of biodiversity. Region size, colonization rate, disturbances, and extinction rates

32. Describe the distance effect and the area effect. The number of species is inversely correlated with distance and the directly correlated with size (area). This refers to islands and their distance from the mainland. 33. Estimate qualitatively the differences in species diversity and abundance of organisms likely to exist on two islands with the following characteristics: Island

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A has an area of 6,000 square miles, and Island B has an area of 60 square miles; both islands lie at 10° N latitude and are equidistant from the same source area of colonizers. 5 to7 times as many species for the 6000 square mile island ( Fig. 42.18 (b)).

Answers:

1. habitat 2. n/a 3. niche 4. n/a 5. commensalism 6. mutualism 7. interspecific 8. Predation (Parasitism), parasitism (predation) 9. symbiosis 10. n/a 11. n/a 12. n/a 13. n/a 14. n/a 15. prey 16. n/a 17. Parasites 18. coevolution 19. n/a 20. n/a 21. social 22. n/a 23. n/a 24. n/a 25. n/a 26. climax 27. n/a 28. climax-pattern 29. n/a 30. n/a 31. stability 32. n/a 33. n/a 34. n/a 35. n/a

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