2. IV. Limiting Factors

3. A. What are they? 1. There are two rules of population ecology a. All populations are capable of exponential growth b. None do 2. Why is rule #2 there, because of limiting factors 3. Any factor, besides carrying capacity, that would cause a decrease of a population is a limiting factor

4. 4. Density dependent limiting factors- depend on the population size 5. Density independent limiting factors- affects same percentage regardless of population size 6. Density dependent show an S shaped curve 7. Density independent show boom and bust curve

7. 8. Examples a. Food limitation b. Predation c. Disease d. Parasites e. Space f. Water g. Climate h. Natural disaster i. Human disturbances

8. 9. How does this affect humans a. Humans are growing exponentially right now b. What limiting factors could cause the most problems for humans

9. B. Biotic Potential 1. Biotic potential is an organisms ability to produce offspring a. Affected by gestation period and litter size

10. 2. K-selected species usually have low biotic potential a. Populations stabilize around carrying capacity (K) b. Lots of competition for survival

11. 3. r-selected species focus on quantity not quality a. Have high biotic potential b. r= rate of population increase without limiting factors c. Usually show great variation in population size