1. Population Ecology
5.01 Investigate and analyze the interrelationships among organisms, populations, communities, and ecosystems

2. What is a population?

3. What causes changes in population size?
  Three factors can affect population size: the number of births, the number of deaths, and the number of individuals that enter or leave the population. Simply put, a population will increase or decrease in size depending on how many individuals are added to it or removed from it.

4. Collecting data about population size
More often than not, the size of a population has to be estimated

5. Techniques of field ecology
Random sampling and quadrant analysis are used to estimate the changes occurring in populations over time.

6. Population density

7. Carrying capacity
The maximum number of individuals in a population that the environment can support (has resources for)
This is determined by both biotic and abiotic factors

8. Abiotic and Biotic factors
Abiotic: weather, natural disasters, available O2, pH, temperature, minerals, moisture
Biotic: food, predators, mates, parasites

9. Population growth graphs
J- curves show exponential growth (explosive)
101 = 10; 102 = 100; 103 = 1000

10. Population growth graphs
An s-shaped curve shows a stable population

11. Limiting factors
Density independent and Density dependent limiting factors control carrying capacity

12. Human Populations Humans are still in the exponential growth phase
The big question is when will our species meet it’s carrying capacity.

13. Why are we interested in the rate of population growth?

14. Resources
Does a population exist independently?

15. If the population of rabbits declined, what might happen to the others?