1. Population Ecology

2. Population
Group of individuals of a single species that occupy the same general area.
Population density = number of individuals
unit area
The number of oak trees per square kilometer in a forest.
The number of earthworms per cubic meter in forest soil.

3. Dispersion patterns
Way individuals in a population are spaced within an area.
Clumped
Uniform
Random

4. Clumped dispersion individuals are grouped in patches.
Most common dispersion patter.
Result of need for resources.

5. Uniform dispersion individuals are equally spaced in the environment
Result of territorial behavior.

6. Random dispersion
individuals in a population are spaced in an unpredictable way
Least common dispersion pattern.

7. Survivorship curve
A plot of the proportion of individuals alive at each age.
Type I
Type II
Type III

8. Type I Survive to old age. Humans, large mammals
Produce few offspring & provides good care.

9. Type II Likelihood of death constant throughout life.
Lizards, rodents, birds.

10. Type III Low survival rate for the very young.
Oysters, invertebrates, seed plants
Produce large numbers of offspring, & little care.

11. Exponential Growth Model
Gives an idealized picture of unregulated population growth.
Bacteria, humans, rabbits

12. Limiting Factors
Environmental factors that restrict population growth.
Food, competition, space, predation