2. Mutualism - both benefit Commensalism - one benefits Parasitism- viruses, bacteria, flatworms, leeches, Symbiotic Relationships

3. Mutualistic relationships Zooxanthellae- in coral, anemones, snails, & giant clams Corals- crabs, shrimp, fish Sponges- nitrogen fixing cyanobacteria Anemone fish- anemone Obligate symbionts- committed, can’t live without

4. Relationships between anemone/fishes Anemone fish Anemone provide provide 1.Protection- drive 1. Safe place away other fish 2. Nest/eggs 2. Sometimes will brooded under feed host anemone

8. Pearl fish typically, they live inside clams, starfish or sea squirts, and are simply commensal, not harming their hosts. However, some species are known to be parasitic on sea cucumbers, living in their gut and eating their sex organs. Commensal relationships

10. Parrot fish Are known for their parrot like beaks which they scrape algae from coral. This distributes coral sand, and prevents algae from choking coral. Can produce 90 Kg of sand a year. To keep up teeth grow continuously. Maneuver with pectoral fins. Excrete mucus cocoon at night to hide scent. Parrot fish must be protected to protect the reef

11. Parrotfish

12. Damsel fish Brightly colored, territorial fish which include anemone fish some defend an area that grows a mat of algae, which they feed on. (garden of algae)

13. Hawaiian Domino Damselfish

14. Damselfish

15. Types of reef 1. Fringing Reefs 2. Barrier Reef 3. Atoll

16. Types of Reefs: 1. Fringing Reefs: Simplest kind Grow in narrow band/ fringe along shore Most vulnerable to pollution runoff

21. 2. Barrier Reef: Farther from shore (up to 60 miles) Separated from shore by lagoon

24. Sand islands form (sand cays)

25. Spur and groove (buttresses) coral with sand channels - form in windward side.

27. Great Barrier Reef/ Belize

28. 3. Atolls: Ring of reef (or cays) surrounding lagoon

29. 3. Atolls: Can be far from land and 1,000 meters deep Darwin solved the puzzle on how it formed fringing reef growth on a subsiding island (volcano).