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Ecology
The best way for scientists to gain valuable insight about the interactions between
organisms and their environments and between different species of organisms is by
observation. By completing such observations, scientists have determined that each
organism, regardless of where it lives, depends on nonliving factors found in its envi-
ronment and on other organisms living in the same environment for survival. In other
words, all living things need both non-living and living things to survive.
For example, green plants provide a source of food for many organisms as well as a
place to live. The animals that eat the plants provide a source of food for other animals.
The interactions and interdependence of organisms with each other and their environ-
ments are not unique. The same type of dependency occurs whether the environment is
a barren desert, a tropical rain forest, or a grassy meadow.
Ecology
is the scientific
discipline in which the relationships among living organisms and the interactions the
organisms have with their environments are studied.
The study of organisms and their environments is not new. The word
ecology
was first
introduced in 1866 by Ernst Haeckel, a German biologist. However, the field of ecology
did not really become prominent until the twentieth century. Since that time, it has
continued to increase in importance and scope. You can see just some of the many
significant milestones in ecology in
Figure 1,
on the next page.
Get It?
Describe
some of the interactions that occur between living and nonliving things
in your community.
FOCUS QUESTION
What relationships among organisms might exist with a bird
nest built in a thorny tree?
LESSON 1
ORGANISMS AND THEIR RELATIONSHIPS
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COLLECT EVIDENCE
Use your Science Journal to
record the evidence you collect as
you complete the readings and
activities in this lesson.
INVESTIGATE
GO ONLINE
to find these activities and more resources.
BioLab:
Explore Habitat Size and Species Diversity
Plan and carry out an investigation
to determine
what effect
increasing the size of a
habitat
has on
species diversity.
Virtual Investigation:
Model Ecosystems
Use a model
to determine
how energy flows
through an ecosystem.
Disciplinary Core Ideas
Crosscutting Concepts
Science & Engineering Practices
3D THINKING
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Module 2 • Principles of Ecology