1. Ecology # 2
Populations

2. What causes populations to
change over time?

3. Population density is the number of individuals per unit area
How crowded a population is
Varies depending on the species & ecosystem

4. How does body mass affect population density?

5. How do individuals of a population arrange themselves in the space?
Depends of the type of species & environment
3 types: uniform, random, clumped

6. What causes population growth?
Three factors:
Birth rates
Death rates
Immigration/migration
Which result in population growth?
Which result in population decline?

7. Exponential growth

8. Logistic growth
Death rates = Birth rates
Immigration = Emigration

9. Carrying capacity
Number of individuals an environment
can support

10. How are human populations changing over time?
Exponential growth? Logistic growth?
Have we reached carrying capacity?