1. Interactions Within Ecosystems

2. Groups of living things interact within ecosystems
The environment can be organized into five levels
Biome : region with similar climate, types of plants, and animals
Ecosystem: The living and non-living things that interact in one environment.
Community: The living organisms of an ecosystem
Population: A group of organisms of the same species that live in the same area.
Organism: A single living thing, made up of one or many cells, that is capable of growing and reproducing.

3. Habitat & Niche
A Habitat is all the biotic and abiotic factors in the area where an organism lives
An Ecological Niche is composed of all the physical, chemical, and biological factors that a species needs to survive, stay healthy and reproduce

4. Resource Availability
Animals in a habitat are located based on food supplies, water, and shelter locations.
Competitive Exclusion when 2 species compete for the same resources,
the one that is better suited to the niche will survive, the other will move to another niche or become extinct
Or…
Niche partitioning
Evolutionary response

5. Ecological equivalents
Species that occupy the same niches but live in different geographical regions - never compete for the same resources

6. Organisms Interact in Different Ways
Organisms may cooperate, compete, or depend on each other for survival

7. Organisms Interact in Different Ways
Competition
Competition is the struggle between individuals or different populations for the same limited resource

8. Predation - one organism captures & feed on another organism (fish in large groups)
Predator/ Prey the location and number of predator populations depends on the numbers of prey (birds feeding on insects migrate to the areas where the insects are plentiful)

9. Survival of One Species Might Depend on Another Species
Symbiosis: two different species who live together in a close relationship
THREE TYPES:
Mutualism
Commensalism
Parasitism

10. Types of Symbiosis
Mutualism: Two species interacting with each other that benefits both species. (bees and flowers)

11. Types of Symbiosis
Commensalism: two species interacting with each other with one species benefiting and the other unaffected. (jellyfish and fish)

12. Types of Symbiosis
Parasitism: two species interacting while one species benefits and the host species is harmed
Examples of human parasites.

13. Population Density
Measurement of the number of individuals living in a defined space
Predator-prey interactions can affect population increase or decrease ( as a wolf population increases the moose population decreases)
Birth rate may decline or increase

14. Four factors affect the size of a population
Immigration: movement of individuals into a population from another population
Births
Emigration: movement of individuals out of a population into another population
Deaths

15. Maintaining a Balance in an Ecosystem
Carrying Capacity: the maximum number of individuals that an ecosystem can support.
Limiting factors affect the carrying capacity

16. Populations Change Over Time
Limiting factors: any factor or condition that limits the growth of a population in an ecosystem
(density dependent: food, water, large group of predators, small group of prey
density independent: light, weather)

17. Ecosystems change over time
Succession: the gradual change in an ecosystem in which one biological community is replaced by another.

18. Primary Succession
Primary succession: The establishment of a new biological community in an area of bare rocks. (plants moving in after a lava flow or glacier retreats)

19. Secondary Succession
Secondary Succession: Occurs after a major disturbance happens and the soil still remains. (forest fire)