Chapter Objectives

1. Define the scope of population ecology
2. Distinguish between population and density
3. Explain how ecologists measure species density
4. Describe conditions which may result in clumped dispersion, random dispersion, and uniform dispersion of populations
5. Explain how age structure, generation time, and sex structure of populations can affect population growth
6. Describe the characteristics of populations which exhibit Type I, Type II, and Type III suvivorship curves
7. Explain how carrying capacity of the environment affects the intrinsic rate of increase of a population
8. Explain how density dependent factors affect population growth
9. Describe how weather and climate can function as density-independent factors in controlling population growth
10. Explain how density-dependent and density-independent factors may work together to control a population's growth
11. List the 3 major characteristics of a life history and explain how each affects the
    1. number of offspring produced by an individual
    2. population's growth
12. Explain how predation can affect life history through natural selection
13. Distinguish between r-selected and K-selected populations
14. Explain how a stressful environment may alter the standard r-selection and K-selection characteristics

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15. Compare and contrast the individualistic hypothesis of H. A. Gleason and the interactive hypothesis of F. E. Clements with respect to communities
16. Explain the relationship among species richness, relative abundance, and diversity
17. List 4 properties of a community and explain the importance of each
18. Explain how interspecific competition may affect community structure
19. Describe the competitive exclusion principle and explain how competitive exclusion may affect community structure
20. Distinguish between an organism's fundamental niche and realized niche
21. Explain how resource partitioning can affect species diversity
22. Describe the defense mechanisms evolved by plants to reduce predation by herbivores
23. Explain how cryptic coloration and aposematic coloration aid an animal in avoiding predators
24. Distinguish between Batesian mimicry and Mullerian mimicry
25. Describe how predators use mimicry to obtain prey
26. Explain the role of predators in community structure
27. Distinguish among parasitism, mutualism, and commensalism
28. Explain why it is difficult to determine what factor is most important in structuring a community
29. Distinguish between primary succession and secondary succession
30. Explain how inhibition and facilitation may be involved in succession
31. Describe how natural and human disturbances can affect equilibrium and species diversity
32. List the factors involved in limiting a species to a particular range
33. Describe the mechanisms which contribute to the global clines in diversity
34. Explain the factors which determine what species eventually inhabit islands

Chapter Terms:

Chapter Outline Framework

1. Characteristics of Populations
   1. Density
   2. Individual spacing
   3. Demography is the study of factors that affect population growth and decline
2. Life History Traits
   1. Life histories are highly diverse by exhibit patterns in their variability
   2. Limited resources mandate trade-offs between investments in reproduction and survival
3. Population Growth Models
   1. Experimental models describe idealized populations in unlimited environments
   2. Logistic growth model considers carrying capacity
4. Regulation of Population Growth
   1. Density-dependent factors regulate population growth by varying with density
   2. Occurrence and severity of density-independent factors are unrelated to population density
   3. Mix of density-dependent and density-independent factors limits growth of most populations
   4. Some populations have regular boom and bust cycles
5. Human Population Growth
   1. Growing exponentially for centuries but will not be able to do so indefinitely
6. Early Hypotheses of Community Structure
   1. Interactive and individualistic hypothesis pose alternative explanations of community structure
7. Interactions Between Populations of Different Species
   1. Intraspecitic interactions can be strong selection factors in evolution
   2. Interspecific interactions may have positive, negative, or neutral effects on population density
   3. Predation and parasitism are +/- interactions
   4. Interspeciffic competitions are -/- interactions
   5. Commensalism is a +/0 interaction
   6. Mutualism is a +/+ interaction
8. Interspecific Interactions and Community Structure
   1. Predators can alter community structure by moderating competition among prey species
   2. Mutualism and parasitism can have community-wide effects
   3. Interspecific competition influences populations of many species and can affect community structure
   4. A complex interplay of interspecific interactions and environmental variability characterizes community structure
9. Disturbance and Nonequilibrium
   1. Nonequilibrium resulting from disturbance is a prominent feature of most communities
   2. Humans are the most widespread agents of disturbance
   3. Succession is a process of change that results from disturbance in a community
   4. The nonequilibrial model views communities as mosaics of patches at different stages of succession
10. Community Ecology and Biogeography
    1. Dispersal and survivability in ecological and evolutionary time account for the geographical ranges of species
    2. Species diversity on islands tends to reach dynamic equilibrium in ecological time

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