1. Benthic Communities living along the bottom of the ocean

2. Benthic Communities living along the bottom of the ocean

3. Benthic Communities Rocky Intertidal Zones Coral Reefs

4. Rocky Intertidal Zones

5. Hard places to live Drying out during low tide –Close shells, move to moist areas Wave Shock –Have holdfasts, cement, tube feet Lack of space to hold on –competition Rapid changes in temperature & salinity –Close shells or be able to withstand it

6. Table 15.1

7. Coral Reefs Corals –Are animals (Cnidarians) –Small (ant-sized) polyps live in large colonies –Hermatypic corals secret a calcium carbonate skeleton…the reef

9. Coral Reefs Zooxanthellae –Dinoflagellate that lives within the coral polyp –A mutualism –Algae provide food, speeds up calcium carbonate deposition & get nutrients in return

10. Coral Reefs Hermatypic Coral’s ideal habitat is 5-10 m (16-33 ft) depth & temperatures warmer than 18-21 o C (64-70 o F)

11. Fig. 14-12, p. 294

12. Coral Reefs Reefs support a large diversity of other organisms –Home to 25% of the world’s marine species

13. Symbiosis the co-occurrence of two species in which the life of one is closely tied with the life of another

14. Symbiosis Three types –mutualism (++) Anemone fish, cleaner shrimp or wrasse, zooxanthellae –commensalism (+0) pea crabs, remoras & shark, whale barnacles –parasitism (+-) isopods, roundworms, etc.

15. Figure 14.15b

16. Figure 10 p.221

17. Figure 14.15a

19. Figure 14.15c