Chapter 1
Science and Marine Biology
Karleskint
Turner
Small
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.
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
Importance of the Oceans
and Marine Organisms
• Marine Organisms:
– provide substantial part
of human food supply
- 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
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
• significance of plankton receives attention marine
studies in the United States
• expeditions of Alexander Agassiz
• 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
• 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
• Scientific method – an orderly pattern of
gathering and analyzing information
Steps in the Scientific Method
• Making observations (Step 1)
• Using inductive reasoning to form a
hypothesis (Step 2)
• Using deductive reasoning to design
experiments (Step 3)
– experimental variable
– experimental set
– control set
Steps in the Scientific Method
• Gathering results (Step 4)
• Drawing conclusions (Step 5)
– theory versus hypothesis
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
Why do salt marsh plants in
some areas grow larger?
1) Make Observations and Ask Questions
Plot 1
Plot 2
Low nutrient input High nutrient input
2) Formulate a Hypothesis
Use
inductive Growth of marsh
reasoning
grass is limited by
nitrogen availability
Short grass
Tall grass
3) Use deductive reasoning to
make a prediction based on the
hypothesis
Soil sample has Soil sample has
IF nitrogen is added to the
low nitrogen
high nitrogen
soil, THEN marsh grass will
4) Design Experiments and Do Them
grow larger or faster or both
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
Add fertilizer lacking nitrogen height Add nitrogen-containing fertilizer
5) Gather Results
Small increases in size, mass,
and growth rate
6) Repeat Experiments and Test More Plots
Large increases in size, mass,
and growth rate
Similar results
7) Draw Conclusions
Availability of nitrogen is a major limiting
factor on the growth of salt marsh plants
*Hypothesis is confirmed
Stepped Art
Fig. 1-11, p. 11
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
• “The science of Marine Biology”
– Introduction to Marine Biology 3rd edition
contains “Science of Marine Biology” features
to illustrate the application of the scientific
method in studying marine organisms