1. Principles of Ecology

2. Types of Organisms: REVIEW!
Autotrophs (Producers)
Photoautotrophs
Chemoautotrophs
Heterotrophs (Consumers)
Herbivores
Carnivores
Omnivores
Scavengers
Decomposers

3. Types of Organisms: Autotrophs
Also called Producers
Organisms that produce their own food from the sun or from chemicals

4. Types of Organisms: Autotrophs
Photoautotrophs
Use photosynthesis to make food
Ex. plants, algae, certain bacteria

5. Types of Organisms: Autotrophs
Chemoautotrophs
Make food from chemicals (chemosynthesis)

6. Autotrophs

7. Types of Organisms: Heterotrophs
Also called consumers
Organisms that make energy from the food they eat

8. Herbivores - eat only plants Examples: cow, deer

9. Carnivores – eat only meat Example: Snakes Owls Lions

10. Omnivores – eat both plants and meat Examples: humans, bears

11. Scavengers – eat dead matter Examples: vultures, crabs

12. Decomposers – break down organic matter Examples: bacteria, fungi, earthworms

13. Energy Flow Through Ecosystems
All the energy of life ultimately comes from the SUN!
Energy flows through an ecosystem in one direction: SUN 
Producers  Consumers

14. Energy Flow Through Ecosystems
Producers (autotrophs) capture the sun’s energy to make food
This energy is passed to consumers (heterotrophs) when they eat the producers
Energy flow is represented by food chains and food webs

15. Food chain: a series or steps in which organisms transfer energy by eating and being eaten
Reminder:
Energy moves from autotrophs to heterotrophs to decomposers (eventually)

16. Food Web Food web: shows complex relationships between organisms
Food webs are more realistic than food chains…
Each step in a food chain or food web is called a trophic level

18. TROPHIC LEVELS
Producer
Primary consumer
Secondary consumer
Tertiary consumer
Decomposer

19. Ecological Pyramids and Trophic Levels
Each trophic level depends on the one before it for energy.

21. Therefore, only 10% of the energy is transferred between levels
Organisms use much of the energy they produce/consume for life processes such as reproduction, movement, and respiration
Therefore, only 10% of the energy is transferred between levels

22. The 10% rule… AMOUNT OF ENERGY FROM ONE TROPHIC LEVEL TO THE NEXT…
PRODUCER PRIMARY SECONDARY
CONSUMER CONSUMER

23. The amount of energy available in an ecosystem can be represented by an ecological pyramid
Higher trophic levels are on top of one another in the pyramid

24. Ecological pyramids can illustrate
Energy…..

25. Ecological pyramids can illustrate
Numbers….(how many are there?)

26. Ecological pyramids can illustrate
Biomass (total weight of living matter)