1. Ecology of Populations (1) Limiting factors that affect populations in an ecosystem Hickox: Baker High School Biology

2. Ecology of Populations (2)__________- Study of the interactions of organisms with other organisms and the physical environment (3)__________ - Place where an organism lives. (4) _______________ All the organisms within an area belonging to the same species. (5) ______________ All various populations interacting at same locale. (6) ______________Community of populations including biotic and abiotic factors. Hickox: Baker High School Biology

3. Ecological Levels Hickox: Baker High School Biology3

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5. Factors that affect population growth and depend on (9)_________ Human (10)____________ such as tuberculosis often become epidemics in crowded cities. Locust plagues Hickox: Baker High School Biology 5

6. Weather Events Temperature 6

7. Regulation of Population Size Density - Dependent Factors – Number of organisms present (13)influences the effect of the factor. (14) Competition (15) Predation (predators) (16) Disease Density - Independent Factors – Number of organisms present does (17) not influence the effect of the factor. (18) Natural Disasters Hickox: Baker High School Biology7

8. Question 1: Which situation is caused by a density-independent limiting factor? A.The influenza outbreak of 1918-1919 killed over 20 million people. (number of organisms was influenced by factor) B.The cones of the jack pine need heat from a fire to help release seeds. (number of organisms was not influenced by factor) C.A parasite alters reproduction in a woodpecker population causing fewer births.(number of organisms was influenced by factor) D.A queen bee regulates the number of eggs she lays according to the amount of food available.. (number of organisms was influenced by factor) Hickox: Baker High School Biology 8 Density - Independent Factors Number of organisms present does not influence the effect of the factor. Natural Disasters and Temperature

9. Question 2 Which limiting factor is density-Independent for rainbow trout? A.Size of the stream (number of organisms was not influenced by factor) B.Spread of parasites (number of organisms was influenced by factor) C.Competition for food (number of organisms was influenced by factor) D.Supply of dissolved oxygen (number of organisms was influenced by factor) Hickox: Baker High School Biology9 Density - Independent Factors Number of organisms present does not influence the effect of the factor. Natural Disasters and Temperature

10. Question 3: Which statement BEST describes the relationship between natural disasters or human-caused disasters and population size? A.Natural and human-causing disasters are density-dependent factors. (Not Natural Disaster) B.Natural and human-causing disasters are density-independent factors. (Natural Disasters are density-independent) C.Human-causing disasters are density-independent whereas natural disasters are density-dependent. (Not Natural Disaster) D.Human-causing disasters are density-dependent whereas natural disasters are density-independent. (Not Natural Disaster) Hickox: Baker High School Biology10 Density - Independent Factors Number of organisms present does not influence the effect of the factor. Natural Disasters

11. Density - Dependent Factors – Number of organisms present influences the effect of the factor. Competition Predation Disease Hickox: Baker High School Biology11 Question 4: Which relationship BEST identifies a density-dependent limiting factor? A.A bobcat population declines due to disease. (number of organisms influence the effect of the factor; competition, predation, disease) B.A fish population declines due to a severe drought.(not competition or predation but natural disaster) C.A bird population declines due to pollution. (not competition or predation but disaster) D. A wolf population declines due to a cold winter. ( Number of organisms present does not influence the effect of the factor.- Independent)

12. Density - Dependent Factors – Number of organisms present influences the effect of the factor. Competition and Predation and Disease Hickox: Baker High School Biology 12 Question 5: Study the table below. Caterpillars can destroy trees by eating too many leaves and making them susceptible to disease or drought. Which student has correctly identified the density-dependent and density-independent limiting factors associated with an invasion of Gypsy Moth Caterpillars? Student Populations of Caterpillars DiseaseDrought 1Density-independentDensity-dependent 2 Density-independent 3 4Density-dependent Density-independent Density - Independent Factors Number of organisms present does not influence the effect of the factor. Natural Disasters

13. Question 6: Study the table below. Which student identified only density-independent limiting factors? Student’s Identification of Density-Independent Limiting Factors Hickox: Baker High School Biology13 Density - Independent Factors Number of organisms present does not influence the effect of the factor. Natural Disasters Density - Dependent Factors – Number of organisms present influences the effect of the factor.  Competition and Predation and Disease

14. Question 7: Which statement BEST explains why a disease my affect one population more than another population? A.Because disease is a density-dependent limiting factor, a larger population makes it easier for the virus to spread from person to person B.Because disease is a density-independent limiting factor, a large population makes it easier for the virus to spread from person to person C.Because disease is a density-dependent limiting factor, climate can influence the disease, making it more or less affective. D.Because disease is a density-independent limiting factor, climate can influence the disease, making it more or less affective. Hickox: Baker High School Biology 14 Density - Independent Factors Number of organisms present does not influence the effect of the factor. Natural Disasters Density - Dependent Factors – Number of organisms present influences the effect of the factor.  Competition and Predation and Disease

15. Uniform Distribution Hickox: Baker High School Biology

16. Random Distribution Hickox: Baker High School Biology

17. Clumped Distribution Hickox: Baker High School Biology