1. Marine Biology Study of living organisms in the ocean LIFE = ? –Ability to capture, store, and transmit energy –Ability to reproduce –Ability to adapt to their environment –NASA: A self-sustained chemical system capable of Darwinian evolution

2. Evolution Explains the unity and diversity of life Charles Darwin and Alfred Wallace Definition? –Change Mechanism = natural selection –reproduction, mutation/variation, selection

3. Diversity of Life

4. Likely between 6- 12 million species total Likely about 1 million marine species 2000 new marine species discovered each year

5. Land is more variable- leads to more species Oceans more stable Ex: temperature

6. Classifying marine organisms Pelagic (in water) –Plankton (drifters) –Nekton (swimmers) Benthic (along the bottom)

7. Life Cycle of a Squid

8. Divisions of the Marine Environment

9. Living in the Ocean: Advantage= Water everywhere makes up large % of living organisms supportive

10. Living in the Ocean: Disadvantage= Hard to move Streamlining in larger organisms

11. Living in the Ocean: Advantage= Hard to move Appendages to slow sinking in plankton

12. Common Problem: Surface Area to Volume Ratios

13. Primary Producers aka autotrophs Organisms that can capture solar energy and convert it to chemical energy by building organic compounds Photosynthesis

14. Fig. 12-2, p. 238

15. Primary Producers Others use chemosynthesis –Much less common –Use the oxidation of inorganic compounds as energy source, –ex: bacteria use hydrogen sulfide at hydrothermal vents

16. Cellular Respiration Opposite of photosynthesis Breakdown of food All organisms

17. Figure 13.1

18. Consumers aka heterotrophs Must consume (eat) other organisms

20. Consumers Primary consumers –Eat producers Secondary Consumers –Eat primary consumers These all are Trophic Levels

21. Food webs Complex representation of who eats who

22. Primary Productivity Refers to how active the producers are grams of Carbon bound into organic material per square meter per year (gC/m 2 /y)

26. Figure 13.18

27. Only 10% of “food” gets transferred to the next trophic level

28. Figure 13.19

29. Ocean’s Primary Producers Algae – in Kingdom Protista –Have chlorophyll but no vessels to conduct fluids –Unicellular = phytoplankton – pelagic –Multicellular = seaweed – benthic Plants –Angiosperms = flowering plants

30. The Pelagic Zone Pelagic organisms are suspended in the water –Plankton = drifters Phytoplankton= unicellular photosynthetic algae Zooplankton = “animal” plankton –Nekton = swimmers

32. Phytoplankton 95% of ocean’s primary productivity Mostly Single-celled organisms Diatoms & Dinoflagellates

33. Diatoms Dominant (>5600 species) Silica shell – two valves Produce large portion of O 2 in ocean and atmosphere

35. Dinoflagellates Mostly autotrophs Most are free living (except zooxanthellae) Two whip-like flagella “Red tides” or HABs (Harmful Algal Blooms)

37. Phytoplankton Distribution Depends on: –light availability –nutrient concentration Varies with: –Depth, Proximity to land, Location on the earth

39. Phytoplankton Distribution Compensation Depth –Where rate of photosynthesis = rate of respiration –Below this phytoplankton will die

40. Phytoplankton Distribution Higher near coast –Runoff –upwelling

41. Figure 13.6

42. Phytoplankton Distribution Varies across the globe – How?

43. Phytoplankton Distribution Tropics –Low –Nutrients trapped below thermocline

44. Phytoplankton Distribution Poles –Mostly Low (except for summer peak) –Insufficient light

45. Phytoplankton Distribution Temperate Regions –Highest overall –sufficient light & nutrients –Spring Peak Increasing sunlight –Fall Peak Increasing mixing of nutrients

47. Zooplankton Animal plankton – many different types Heterotrophic – primary consumers Based on the phytoplankon abundance graph…how would you expect zooplankton abundance to vary?

48. Figure 13.11a: Arctic Ecosystem

49. Figure 13.13a: Temperate Ecosystem

51. Zooplankton Major types – –Radiolarians –Foraminifers –Copepods –Krill

52. Zooplankton Holoplankton –Spend their entire life in plankton Major types – –Radiolarians –Foraminifers –Copepods –Krill –Jellyfish (cnidarians) and comb jellies (ctenophores)

53. Figure 14.3: Radiolarians Single- celled; Hard shell made of silica

54. Figure 14.4: Foraminifers Single-celled; shell made from calcium carbonate

55. Copepods Small crustaceans (<1 mm) Very abundant

56. Figure 14.5: Copepod diversity

57. Fig. 13-9, p. 265 Krill – Important in Antarctic Ecosystem

59. Fig. 13-10c, p. 266

60. Zooplankton Meroplankton –Only found in plankton for part of their life cycle –Larvae of benthic adults & fish

61. Meroplankton