1. Limits to Population Growth

2. What slows the growth of populations?
Limiting Factors
Density-dependent limiting factors: limiting factors that are dependent on population size
Density-independent limiting factors: limiting factors that affect the same percentage of a population regardless of its size.

3. Density-dependent limiting factors
Food supply
Predation
Disease
Related to competition and interactions between organisms.
Greater effect in larger populations.

4. Density-dependent limiting factors
Populations controlled by density-dependent factors show an S-shaped curve on a graph.
Exponential growth at first, then growth slows and stops at the carrying capacity. p.81

5. Density-independent factors
Natural disasters
Hurricane
Fire
Tsunami
Limit growth of population by destroying habitat.

6. Density-independent limiting factors
Populations controlled by density-dependent factors show a boom and bust on a graph
Exponential growth when conditions are favorable, then many die when conditions change.
Thrips, aphids, and other
Insects (pg 127)