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Alasdair Turner/Aurora Photos/Alamy
Scientists who study ecology are called
ecologists. Ecologists observe, experiment,
and model using a variety of tools and
methods.
Ecologists like the one shown in
Figure 2
perform tests to determine relationships
among groups of organisms and environ-
mental factors. Results from these tests
might give clues as to why organisms are
able to survive in a particular body of
water, why organisms become ill or die
from drinking the water, or what organ-
isms could live in or near the water.
Ecologists also observe organisms to
understand the interactions among them. Because all organisms in an ecosystem are
connected (either directly or indirectly), understanding relationships can be challeng-
ing. Like all scientists, ecologists rely on scientific models to help them perform tests.
Scientific models are a way of creating a visual representation to answer a question or
test a hypothesis. When you hear the word “model,” you may think of a physical model,
such as a model of the human heart. Scientists also use mathematical models, such as
equations, and computer models.
A model allows a scientist to simulate a process or system. Studying organisms in the
field can be difficult because there often are too many variables to study at one time.
Models allow ecologists to control the number of variables present and to slowly intro-
duce new variables in order to fully understand the effect of each variable.
For example, the scientist in
Figure 2
may wish to determine how a particular group of
seals might be affected by the number of fish in their environment. It would be
extremely difficult, if not impossible, to control all of the variables in an area of the
environment. Attempting to control variables in an experiment would also likely cause
further damage to the environment. The scientist can use a computer model to run
simulations to test different ways of solving a problem, such as a fewer fish being
available for the seals to eat. Data generated by the model can be presented to persuade
conservationists and policy makers about what steps should be taken to help the seals.
WORD ORIGINS
ecology
comes from the Greek words
oikos
, meaning
house
, and
ology
, meaning
to study
.
Figure 2
Ecologists work in the field and in laboratories. This
ecologist is enduring harsh conditions to study seals.
Get It?
Explain
how physical and computer models can help design a solution for an
ecological problem.
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Module 2 • Principles of Ecology