1. Energy Flow in Ecosystems Cycles in Ecosystems

2. Energy for living things starts with the sun * *Except for chemotrophic bacteria

3. Food chains show how the energy is passed from one organism to another in an ecosystem

4. Plants use sunlight to make glucose (main food energy molecule in living things)

5. ► Arrows point from the source of food/energy to the organism getting the energy:  Pizza Human  (just like the “point” of a pizza slice points to you) ► A complete food chain must start with a producer (plant) and end with a decomposer (bacteria, fungus, etc). ► Consumers are animals that eat plants or other animals

6. Herbivores eat plants Ex: rabbits, deer, tortoises Carnivores eat other animals Ex: lions, seals, snakes, salmon Omnivores eat both plants and animals Ex: bears, humans (“vore” suffix = what an animal eats) Scavengers eat the remains of dead animals Types of Consumers:

7. Decomposers & Detritivores convert dead plants and animals into simple substances (humus). Mainly bacteria & fungi.

8. A food web consists of several inter-connected food chains

14. Everglades Food Chain

15. Energy does NOT cycle through ecosystems One-way flow: starts with the sun, ends as heat radiating into space

16. Energy transfer in ecosystems is very inefficient

17. ► As energy moves from one organism to another, most of it is lost as heat  Some energy is stored in the organism ► Plants store energy as starch ► Animals store energy as fat ► Only about 10% is passed to the next consumer

18. The “higher” an organism is in a food chain, the less energy is available ► Energy Pyramid

20. Producers (plants) are always at the base. “Apex” predators are at the top.

21. Usually there are many more prey animals in an ecosystem than predators

23. Keystone Species ► A species that plays a critical role in maintaining the biodiversity of an ecosystem, relative to their abundance in the ecosystem Often a predator that keeps many other species under control Ex: sea stars control numbers of mussels

24. National Geographic: Keystone Species

25. Example: Wolves of Yellowstone ► Reduced elk population ► Resulted in increased growth of stream side vegetation ► Stream habitat improved Wolves Impact on Yellowstone

26. Sea otters are considered a keystone species because: Sea Otters Kelp Forests