Population Ecology Student Outline – r and K Selection
r and K Selection
1.
Introduction
dN1 / dt = r1N1
dN1 / dt = r1N1
A.
r -Selected Individuals
•
Environmental Characteristics
•
Rapid Reproduction
•
Density Independent Mortality
•
Many Small Young Favored
•
Energy Allocation
B.
K-Selected Individuals
•
Environmental Characteristics
•
Carrying Capacity
•
Density Dependent Competition
•
Energy Allocation
C.
r and K Selection and the Role of the Environment
i.
Determining Issues
a.
Energy
b.
Reproduction
c.
Other Issues
ii.
r-Selection
a.
Characteristics
•
Note: Figure 6.9 - Positive Feedback System
iii.
K-Selection
a.
Characteristics:
•
Note: Figure 6.10 - Positive Feedback System
Examples of r and K Environments
D.
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Population Ecology Student Outline – r and K Selection
E.
2.
i.
r-Environment
ii.
K- Environment
Examples of r and K Selection
i.
Across Taxa
ii.
Within Species
•
Figure 6.11
a.
Poa annua (meadow grass)
•
Population #1
•
Population #2
iii.
Sarcophagid Fly
Limitations of the r/K Scheme
A.
Litorina sp. study
•
Figure 6.12
i.
The Speices
•
Littorina saxatalis
a.
Littorina rudis
•
Viviparous
b.
Littorina nigrolineata
•
Oviparous
ii.
Habitats
Figure 6.12 and Table 6.6
a.
Crevice Habitat
b.
Boulder Habitat
iii.
Observations
a.
Crevice Habitat
b.
Boulder Habitat
iv.
Conclusion
“A life-history strategy, is, therefore, an organism’s unique
adaptive response to its whole environment; and
simplistic theories must eventually give way to the
detailed study of real organisms in the real world”
- Begon, Mortimer, Thompson
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