CHAPTER 52 POPULATION ECOLOGY

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CHAPTER 52POPULATION ECOLOGY

• I. Population - a group of individuals of the
  same species that live in the same area 2
  important characteristics
• A. density - number of individuals per unit
  area
• B. dispersion - pattern of spacing among
  individuals
• 1. clumped
• 2. uniform
• 3. random

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Population Ecology (cont.)

• II. Populations change in 2 ways
• A. change in population size the study of
  vital statistics (birth death rates and
  emigration immigration rates) that affect
  population size - demography
• B. evolution - Chapter 22-24

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A. demography

• 1. age structure sex ratio
• 2. life tables survivorship curves
• a. type I survivorship curve
• b. type II survivorship curve
• c. type III survivorship curve

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demography (cont.)

• 3. population growth models
• a. exponential growth - population grows at
  its maximum rate intrinsic rate of
  increase (rmax)
• b. logistic growth - incorporates effect of
  population density on r r0 at carrying
  capacity (K)

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demography (cont.)

• 4. population limiting factors
• a. density-dependent factors
• b. density-independent factors

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B. evolution - life history

• 1. patterns in life history traits
• 2. trade-offs constraints
• 3. life history traits
• a. number of reproductive events per
  lifetime semelparity vs. iteroparity
• b. number of offspring per reproductive
  event
• c. age at first reproduction

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life history (cont.)

• 4. two extreme life history strategies
• a. K-selected populations - maximize
  competitive ability efficiency of resource
  utilization
• b. r-selected populations - maximize
  fecundity rate of maturation