1. Ecosystems

2. What is an Ecosystem?
Ecosystem – A community of organisms in a given area and the abiotic factors that affect them.

3. Habitat and Niche
Habitat – A place where animals and plants naturally live and grow.
Niche – A habitat that
supplies the factors
necessary for existence.
Also, the ecological
role of an organism
in its community.

4. Abiotic vs. Biotic Factors
Abiotic – All the nonliving factors in an area.
Examples: water availability, amount of sunlight, temperature, precipitation, etc.
Also includes Nitrogen and Carbon Cycles
Biotic – All the living factors in an area.
Examples: plants,
animals, bacteria, etc.

5. Populations in Ecosystems
Population – A group of organisms belonging to the same species that live in a particular area.
What kinds of things influence a Population?
What makes Population Numbers increase?
What makes Population Numbers decrease?

6. Competition
The relationship between living things that depend on the same resources in the same place at the same time.

7. Cooperation
Type of animal behavior in which social animals live and work together for the good of the group.

8. Population Factors Things that effect a population…
Density-Dependent Factors – Factors triggered by overpopulation or overcrowding.
Examples: Competition (food, water, shelter), Predation, Parasitism, and Disease.
Density-Independent Factors – Factors that occur regardless of the population.
Examples: Weather or climate change, Natural disasters, and Human activities (pollution)

9. Population Simulation
Watch the Simulation and observe how the bunny population changes when Biotic and Abiotic Factors are introduced.
Answer the questions on your paper.

10. Symbiotic Relationships
Species may form relationships with other species to increase the chance of survival
Symbiosis - a close relationship between organisms of different species in which at least one organism benefits.

11. Commensalism: a symbiotic relationship in which one species benefits and the other is unaffected.
Ex: Spanish moss and a tree
Mutualism: a symbiotic relationship in which both species benefit.
Ex: Ants and acacia trees
Ex: Teeth cleaner birds

12. Parasitism: a symbiotic relationship in which one species benefits and the other is harmed.
Ex: Ticks,
tapeworms,
tree fungus

13. Food Web Animal Name Clarification
Large Fish
Gulls and Terns
Wading Birds
Bivalves
Small Fish
Benthic Invertebrates
Herbivorous Ducks