Chapter 1 Science and Marine Biology Karleskint Small Turner

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.

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.

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.

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

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

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.

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

Marine Biology: A History of Changing Perspectives Beginnings of modern marine science –Challenger expedition exploring world’s oceans Mid 19 th 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

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

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

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?

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 »For example: All fish that have been studied so far have gills. Therefore, clownfish must have gills.

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

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

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?