13.1 Ecologists Study Relationships
Objective
Students will summarize the
different levels of organization
that ecologists study AND will
be able to describe research
methods ecologists use to
study the environment
13.1 Ecologists Study Relationships
Standard
6 b.
Students know how to analyze
changes in an ecosystem resulting
from changes in climate, human
activity, introduction of nonnative
species, or changes in population
size.
13.1 Ecologists Study Relationships
Key Concept
Ecology is the study of the relationships
among organisms and their environment.
13.1 Ecologists Study Relationships
What does the word relationship
mean to you?
13.1 Ecologists Study Relationships
• Ecology is the study of the interactions among living
things, and between living things and their surroundings.
In what
ways
could we
study this
bear?
13.1 Ecologists Study Relationships
• A bear’s
interactions with
other living
things
• Social
interactions with
other animals
• Plants
• Between living
things
• What animals and
plants does it
interact with?
• In its surrounding
• Where it lives
• What does it eat?
13.1 Ecologists Study Relationships
Study this picture
13.1 Ecologists Study Relationships
What sorts of things do you notice
13.1 Ecologists Study Relationships
1. An organism is an
individual living thing
Ex: alligator
Organism
Organism
13.1 Ecologists Study Relationships
2. A population is a group of
the same species that lives in
one area
Ex: alligators
Population
Population
13.1 Ecologists Study Relationships
3. A community is a group of
different species that live together
in one area.
Ex: alligators, turtles, and birds.
Community
Community
13.1 Ecologists Study Relationships
4. An ecosystem includes all of the
organisms as well as the climate
Ex: All animals, plants, soil, water,
rocks and other nonliving things
Ecosystem
Ecosystem
13.1 Ecologists Study Relationships
5. A biome is a major regional or global
community of organisms characterized
by the climate conditions and plant
communities that thrive there.
Biome
13.1 Ecologists Study Relationships
• Ecologists study environments at different levels of
organization.
13.1 Ecologists Study Relationships
With your table: Pick an animal
Organism: 1 animal (Alligator)
Population: animals (Alligators)
Community: animals and plants
(Alligators, turtles, birds, moss,)
Ecosystem: living and non-living
Biome: desert, ocean, chaparral, rainforest,
forest, mountains, fresh water, grassland,
savanna, etc… (p. 463)
13.1 Ecologists Study Relationships
Ecological research methods:
• Observation is the act of carefully watching something
over time.
13.1 Ecologists Study Relationships
Observations of populations can be done by visual
surveys.
–Direct surveys used for
species that are easy to
follow. Ex: You count
how many deer are in the
field
–Indirect surveys are used
for species that are difficult
to track and include looking
for other signs of their
presence. Ex: Looking for
feces or a recent kill
13.1 Ecologists Study Relationships
Experiments can be performed in the lab or the field
• Lab experiments
• Give researchers control
Ex: You want to test how a fungus reacts to heat,
so in your lab experiment you turn up the
temperature.
• Done inside
Negative: not reflective
of the complex
interactions in nature.
13.1 Ecologists Study Relationships
Field experiments
• give a more accurate picture of how organisms
interact in a natural setting
•performed where the organisms live. Ex: In the forest
Negative: may not help determine actual cause and
effect. Ex: You want to know the effect deer have
on a type of grass in the forest, so you block off a
part of the forest to keep out the deer. By
monitoring the fenced and unfenced area, you can
determine the deer’s effect on the grass.
13.1 Ecologists Study Relationships
If observation and experimentation don’t work…turn to
modeling
• Computer and mathematical models can be used to
describe and model nature. Ex: GPS transmitter
• Modeling allows scientists to learn about organisms or
ecosystems in ways that would not be possible in a
natural or lab setting.
Ecologists use data transmitted by
GPS receivers worn by elephants to
develop computer models of the
animal’s movements.
GPS
transmitter
13.1 Ecologists Study Relationships
Discuss with your neighbor:
What are the 5 levels of
organization?
Name the 3 general methods
used by ecologists to study
organisms.