1. Community interactions

2. What’s a community? All the living things in an area
Habitat: the place an animal lives
Niche: an animal’s job, or function in the community
What plants and animals live in an oak woodland community?

3. Rolls in a community Producers: The organisms that can make food
blue-green bacteria, plants
Consumers: organisms that must eat other organisms
Animals
Decomposers: Get their energy by breaking down dead matter
bacteria, fungi, worms

4. Relationships in a community
Many different relationships are found between organisms in every community
predator/ prey
Symbiosis
Mutualism
Commensalisms
Parasitism

5. Predation One organism eats another The one being eaten always dies
The predator benefits the prey does not
+/-
Ladybug beetle preying on an aphid. (Source: Photo by Graham Shepard, Rothamsted Research)

6. Symbiosis Any relationship in which two species live closely together
One example is lichen: algae & fungus live as one

7. Mutualism a symbiotic relationship in which both species benefit
cleaner fish & moray eel
+/+

8. Commensalisms
Relationship where one organism benefits & the other is neither harmed nor helped.
epiphytes and their host trees,
+/ 0

9. Parasitism One organism lives at the expense of another
The parasite is helped, the host is harmed
+/-
Tapeworm life cycle

10. Review What kind of relationship is it when both organisms benefit?
What is it called when one organism benefits and the other is not effected?
What is this picture an example of?