Community Interaction 14.2

1. Community Interaction14.2

2. 14.2 Community Interactions • when organisms live together in an ecological community they interact constantly. • Three types of interactions • Competition • Predation • Symbiosis

3. Competition- competing for resources • occurs due to a limited number of resources • Resource- any necessity of life. water, nutrients, light, food. • Competitive exclusion principle- no two species can occupy the same niche in the same habitat at the same time

4. Competition

5. Predation • Predation- when an organism captures and feeds on another organism. • Predator- hunter • Prey- hunted

7. Symbiosis • Symbiosis- any relationship where two species live closely together. (3 types) • Mutualism • Commensalism • Parasitism

8. Symbiosis • Mutualism- both species benefit from a relationship. • Lichens (fungus and Algae) One example is the lichens, little non-descript patches of stuff you see growing on rocks and tree bark. This is a symbiosis, consisting of a fungus and an alga. The fungus provides a protective home for the algae, and gathers mineral nutrients from rainwater and from dissolving the rock underneath. The alga gathers energy from the sun. There are thousands of species of lichen in the world; actually thousands of species of fungi with just a few species of algae which can form a partnership with almost any of them.

9. Mutualism example:Cleaner birds and Crocodiles

10. Symbiosis • Commensalism – One member of a symbiotic relationship benefits and the other is neither helped or harmed • Ex. Holes used by bluebirds in a tree were chiseled out by woodpeckers after it has been abandoned

11. Clown fish + anemones

12. Symbiosis • Parasitism- One creature benefits and one creature is harmed • Ex tapeworm. Feeds in a humans intestines absorbing his/her nutrients.

13. Relationships: Symbiosis = Living Together a) commensalism b) mutualism c) parasitism

14. Identify these relationships