Chapter 1 Science and Marine Biology

1. Chapter 1 Science and Marine Biology Karleskint Turner Small

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. • We will discuss this further later.

5. Importance of the Oceans and Marine Organisms • World ocean covers nearly 71% of earth’s surface • 99% of the Earth’s biosphere (livable space) is in the ocean • Oceans interacting with the atmosphere affect weather patterns on a global scale

6. Importance of the Oceans and Marine Organisms • Marine Organisms: • provide substantial part of human food supply • Unfortunately, we have overharvested these resources • are used as subjects of scientific study for many areas of research • are useful to medicine and industry providing jobs for many people worldwide

7. Study of the Sea and Its Inhabitants • Oceanography • study of the oceans and their phenomena, such as waves, currents and tides • 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 - traced back to ancient Greeks and Romans - Aristotle and the “ladder of life”, a scheme of classification • Renewed interest in marine organisms • voyage of the HMS Beagle and Charles Darwin’s On the Origin of Species, theory on evolution through natural selection • discovery of deep sea organisms on retrieved transatlantic telegraph cable • This was a cable that was placed across the Atlantic for early communication (before the days of satellites). • When it was pulled up, deep sea organisms were observed growing on it

10. Marine Biology: A History of Changing Perspectives • Beginnings of modern marine science • Challenger expedition exploring world’s oceans • Mid 19th century • First voyage dedicated just to science exploration • Before that, scientists were invited to join other expeditions • 4,700 new species collected and described • Lots of specimens were collected – took 19 years to go through the data • funding of the first marine biology laboratory: Anderson Summer School of Natural History, predecessor of the Marine Biological Laboratory at Woods Hole • forerunner of other U.S. marine laboratories

12. 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 • More research funded to solve problems and to determine human impacts • Marine biology today • deep-sea submersibles • discovering ties between terrestrial and marine environments • information sharing via the Internet

13. Process of Science • Hypothesis • explanations that can be tested by experiments • Has to be testable • Not just an “educated guess” • Scientific method – an orderly pattern of gathering and analyzing information

14. Steps in the Scientific Method • Making observations (Step 1) • Form a hypothesis (Step 2) • Design experiments (Step 3) • experimental variable • experimental set • control set • Experiment has to be repeated and reproducible • Gather results (Step 4) • Statistical analysis, are the results significant? • Draw conclusions • Support or reject the hypothesis • Never “prove” a hypothesis – why?

15. Inductive reasoning vs. deductive reasoning • Inductive reasoning – using individual observations to come to general conclusion • For example: tuna, shark, and sailfish all have gills. Therefore, ALL fish must have gills. • Deductive reasoning – using general principles to come to specific conclusions • Used more in science • For example: All fish that have been studied so far have gills. Therefore, clownfish must have gills.

16. Steps in the Scientific Method EXAMPLE: • Plant growth in a salt marsh: a case study of the scientific method • observation of growth patterns and analysis of soil samples • experiment to test hypothesis • analysis of results of the experiment

20. Process of Science • Alternative methods of science • experimentation is not always possible • observational science – observation alone must be used to support or deny the hypothesis

21. Scientific Theory • The word “theory” is used differently in everyday speech • In biology, a theory is supported by years of research, evidence, and is supported by the scientific community. • We do not have laws in biology – why not?