Key Concepts

2. Key Concepts • Marine and terrestrial environments are interrelated, interactive, and interdependent. • The ocean is an important source of food and other resources for humans. • Marine biology is the study of the sea’s diverse inhabitants and their relationships to each other and their environment.

3. Key Concepts • The history of marine biology is one of changing perspectives that have shaped the modern science and its applications. • Marine laboratories play an important role in education, conservation, and biological research.

4. Key Concepts • It is important to study marine biology in order to make informed decisions about how the oceans and their resources should be used and managed. • Scientists use an organized approach called the scientific method to investigate natural phenomena.

5. Importance of the Oceans and Marine Organisms • World ocean covers nearly 71% of earth’s surface • Oceans interacting with the atmosphere affect weather patterns on a global scale

6. Importance of the Oceans and Marine Organisms • Marine Organisms Provide: • Food • Research • Medicine • Jobs

7. Study of the Sea and Its Inhabitants • Oceanography • study of the oceans and their phenomena, such as waves, currents and tides

8. Study of the Sea and Its Inhabitants • Marine biology • study of the living organisms that inhabit the seas and their interactions with each other and their environment • Knowledge of these disciplines will promote marine conservation.

9. Marine Biology: A History of Changing Perspectives • Early studies of marine organisms - ancient Greeks and Romans - Aristotle and the “ladder of life”

10. Marine Biology: A History of Changing Perspectives • Renewed interest in marine organisms • Charles Darwin’s On the Origin of Species • discovery of deep sea organisms on retrieved transatlantic telegraph cable

11. Marine Biology: A History of Changing Perspectives • Beginnings of modern marine science • Challenger expedition exploring world’s oceans • 4,700 new species collected and described

12. Marine Biology: A History of Changing Perspectives • Beginnings of modern marine science • Challenger expedition exploring world’s oceans • significance of plankton

13. Marine Biology: A History of Changing Perspectives • Beginnings of modern marine science • Marine Studies in the United States • expeditions of Alexander Agassiz

14. Marine Biology: A History of Changing Perspectives • Beginnings of modern marine science • Marine Studies in the United States • Funding of the first marine biology laboratory

15. Marine Biology: A History of Changing Perspectives • Marine biology in the twentieth century: • Fridtjof Nansen’s Arctic expedition • Sir Alistair Hardy’s Antarctic expedition • impact of human activities on marine environment gains attention

16. Marine Biology: A History of Changing Perspectives • Marine biology today • deep-sea submersibles • discovering ties between terrestrial and marine environments • information sharing via the Internet

17. Process of Science • Hypothesis • explanations that can be tested by experiments • Scientific method – an orderly pattern of gathering and analyzing information

18. Make Observations and Ask Questions 1 Why do salt marsh plants in some areas grow larger? Plot 1 Low nutrient input Plot 2 High nutrient input Formulate a Hypothesis 2 Use inductive reasoning Growth of marsh grass is limited by nitrogen availability Short grass Tall grass Use deductive reasoning to make a prediction based on the hypothesis 3 Soil sample has low nitrogen Soil sample has high nitrogen IF nitrogen is added to the soil, THEN marsh grass will grow larger or faster or both Figure 1-11a p11

19. Steps in the Scientific Method • Make observations • Form a hypothesis • Design experiments • experimental variable • experimental set • control set

20. IF nitrogen is added to the soil, THEN marsh grass will grow larger or faster or both Design Experiments and Do Them 4 Control plot 1 Area 1 Control plot 2 Area 2 Experimental plot 1 Area 1 Experimental plot 2 Area 2 All plants are initially the same height Add fertilizer lacking nitrogen Add nitrogen-containing fertilizer Gather Results 5 Figure 1-11b p11

21. Steps in the Scientific Method • Gathering results (Step 4) • Drawing conclusions (Step 5) • theory versus hypothesis

22. Small increases in size, mass, and growth rate Large increases in size, mass, and growth rate Repeat Experiments and Test More Plots 6 Similar results Draw Conclusions 7 Availability of nitrogen is a major limiting factor on the growth of salt marsh plants *Hypothesis is confirmed Figure 1-11c p11

23. Process of Science • Alternative methods of science • experimentation is not always possible • observational science • “The science of Marine Biology”