1. Population dynamics

2. Exponential Growth
Exponential growth of a population of organisms occurs when the # of organisms rises at an ever-increasing rate.

3. Population Growth of Houseflies
1 million
500,000
100
One year
Population size

4. What are some things that prevent populations from growing exponentially?

5. Carrying Capacity
The number of organisms that a particular environment can support over an indefinite period of time.
Births will exceed deaths until carrying capacity is reached

6. Number of Yeast Cells
Time (hours)
Carrying capacity
Carrying capacity

7. 4 population growth graphs

8. Exponential vs. Logistic growth

9. Limiting factors
Density-dependent
Density-independent
Predation

10. Limiting factors Density-dependent
Have an increasing effect as population increases
Ex. Disease, parasites, competition, crowding & stress
Density-independent
Affects all populations, regardless of their density
Usually abiotic factors: ex. storms, floods, temp, fire
Predation – keeps population size within limits (density-dependent)

11. Practice Intense heat wave
Classify each of the following as either density-dependent or density-independent.
Intense heat wave
Large population of caterpillars infected with wasp larvae parasites
Overpopulation of an organism
Clear cutting of a forest to build a shopping center.

12. Exotics Species living in an area to which they are not native
Can be introduced accidentally or on purpose
Ex. Sika from Asia brought to South TX

13. How do you think introducing Sika into the population would affect the native population of deer?