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2010-06-08 19:00:37

Ecology notes
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  1. What are the four characteristics of a community?
    • 1. Species richness and relative abundance of different species.
    • 2. Dominant species
    • 3. Response to disturbances
    • 2. Trophic structure-the feeding relationships among the various species
  2. What are the four types of interactions in communities?
    • Competition
    • Predation
    • Symbiosis
    • Herbivory
  3. What is interspecific competition?
    between species
  4. What is intraspecific?
    within a species
  5. What is the Competitive Exclusion Principal?
    This is the concept that two species competing for the same limiting resources cannot coexist in the same community. One will use resources more efficiently, thus reproduce more rapidly and eliminate the inferior competitor.
  6. What is resource partitioning?
    Or one species may evolve to use a different set of resources
  7. What is Batesian Mimicry?
    When a nonpoisonous species mimics a poisonous species
  8. What is Mullerian Mimicry?
    When two poisonous species mimic each other
  9. What is a keystone species?
    A keystone species is a species that plays a critical role in maintaining the structure of an ecological community and whose impact on the community is greater than would be expected based on its relative abundance or total biomass.
  10. What is parasitism?
    One organism harmed and the other helped.
  11. What is commensalism?
    One organism is helped and the other is neither harmed nor helped.
  12. What is mutualism?
    Both organisms benefit
  13. What is ecological succession?
    A predictable and orderly changes in the composition or structure of an ecological community.
  14. What is primary succession?
    • begins in a virtually lifeless area with no soil. New volcanic islands rubble left by a retreating
    • glacier.
  15. What is secondary succession?
    When a disturbance destroys an existing community.
  16. Explain the water cycle.
  17. Explain the carbon cycle.
  18. Explain the nitrogen cycle.
  19. Explain the phosphorus cycle.
  20. How many directions does energy flow?
  21. What is the population density?
    # of individuals of a species per unit area or volume
  22. What is the dispersion pattern?
    the way individuals are spaced within their area.
  23. What is the most common dispersion pattern?
    Clumped pattern.
  24. What is a survivorship curve?
    Plot the proportion of individuals alive at any given at each age
    • •I – fewer offspring but live longer
    • •II – mortality is more constant over the life span.
    • •III – high death rates for very young and then a period when death rates are lower for those who survive.
  25. What is the exponential growth model?
    Growth idealized. J curve
  26. What is the logistic growth model?
    S curve
  27. What are "Boom & Bust" cycles?
    • Occur with some regularity
    • –ex: lynx & hare cycles every 10 years
    • –food shortages, predator-prey interactions, or combinations of both
  28. What are the key life history traits?
    • Age at which reproduction first occurs
    • The frequency of reproduction
    • The number of offspring
    • Amount of parental care given.
  29. What is R selection?
    Smaller organisms. They reproduce quickly
  30. What is the K selection?
    Bigger organisms. In stable and predictable environments. Longer life expectancy.