Grades 9-12 Performance Task
Contributed by: Oregon State Department of Education
Description:
Students will conduct simple sampling of plant and insect biodiversity
at ground level in two contrasting environments of their own choosing.
Students need not identify each species found, only recognize different
species and be able to compare and contrast species numbers in the
two habitats.
The task assesses students' understanding of biodiversity, including
an understanding that biodiversity can be quantified in many different
ways; the importance of biodiversity in ecosystem stability and
resilience; and that biodiversity(as measured by species richness)
is different in different habitats due to environmental factors.
This task also assesses experimental design.
This task is designed to take students approximately 2 periods
in class for discussion, instruction, Internet searches (if used).
Overall Task Content Area:
- Life Science
Specific Knowledge Areas:
- Effect of various species on ecosystems
- Structure and function in biological systems
Performance Expectations:
- conducting investigations
- using equipment
- gathering, organizing, and representing data
- formulating conclusions from investigational data
National Science Education Standards:
12 A SI 1: Abilities necessary to do scientific
inquiry: Grades 9-12
1.3 Use technology and mathematics to improve
investigations and communications. A variety of technologies, such
as hand tools, measuring instruments, and calculators, should be
an integral component of scientific investigations. The use of computers
for the collection, analysis, and display of data is also a part
of this standard. Mathematics plays an essential role in all aspects
of an inquiry. For example, measurement is used for posing questions,
formulas are used for developing explanations, and charts and graphs
are used for communicating results.
1.4 Formulate
and revise scientific explanations and models using logic and evidence.
Student inquiries should culminate in formulating an explanation
or model. Models should be physical, conceptual, and mathematical.
In the process of answering the questions, the students should engage
in discussions and arguments that result in the revision of their
explanations. These discussions should be based on scientific knowledge,
the use of logic, and evidence from their investigation.
12 C LS 4: The interdependence of organisms: Grades
9-12
4.3 Organisms both cooperate and compete
in ecosystems. The interrelationships and interdependencies of these
organisms may generate ecosystems that are stable for hundreds or
thousands of years.
4.5 Human beings live within the world’s ecosystems.
Increasingly, humans modify ecosystems as a result of population
growth, technology, and consumption. Human destruction of habitats
through direct harvesting, pollution, atmospheric changes, and other
factors is threatening current global stability, and if not addressed,
ecosystems will be irreversibly affected.
(Use the "hot" link on the PALS
home page to check the full text of related National Science
Education Standards, if desired.)
General Instructions to the Teacher:
This task is designed to take students approximately 2 periods
in class for discussion, instruction, Internet searches (if used).
.
Students should be ready to work as soon as periods begin. A central
supply area, if needed, should be easily accessible. All supplies
should be clearly labeled.
Materials for " Suburban Ecosystems":
The student will need:
- graph paper
- computer resources (if available)
- 0.5 meter sampling grids (constructed from wood lath or pvc
pipe)
Advance Preparation:
- As part of the initial introduction to the ecological characteristics
of life on Earth (reproduction, energy processing, cycling, homeostasis,
diversity), discuss the concept of biodiversity as number and
types of species in a given area. In a full or partial class period,
allow student teams (2-3 students) to use the Internet and Worldwide
Web search engines to find basic information about biodiversity.
How it is defined, how it is measured, what areas are the most
and least diverse areas on the planet, and what are the advantages
and disadvantages of diversity in an ecosystem are all possible
questions to use to direct their searches. You may wish to do
this as a team search contest, or simply by providing a list of
questions to answer. (As of March, 1998, several biodiversity
sites contained links to this information, so it should be relatively
simple for students to find.)
Once students have found the information, use their answers as
a springboard to further discussions about what influences diversity
in various ecosystems. Provide students with a set of observations
(simulated or actual measurements) that indicate that different
terrestrial environments characteristically support different
levels of biodiversity.
Sample Data (simulated): This data can be used to spark
a discussion of the influence of different environments on Plant
communities that appear from a causal observation to be very similar.
All data shown below were collected on suburban "lawn" areas,
on flat ground, exposed to full sun, moderate foot traffic, and
subject to frequent mechanical mowing.
Landscape/Location
|
Plant Species
|
Animal Species
|
Total Species
|
Manila, Philippines
|
16
|
12
|
28
|
Los Angeles, CA
|
2
|
4
|
6
|
Seattle, WA
|
7
|
9
|
16
|
Salem, OR
|
8
|
3
|
11
|
Sedona, AZ
|
2
|
0
|
2
|
Brainstorm possible reasons why, advantages, disadvantages to
high biodiversity, or other issues that arise. Discuss the simplest
possible techniques for diversity determinations. These would
typically involve .5 to 1-meter square plots--based on appearance
only. They need not actually identify species names. Include plants
(grass, shrubs, and/or weeds) and animals (usually insects and
worms).
As part of the discussion, it would be beneficial to take students
to lawn areas around the school and have them practice sampling
techniques. Consider producing 0.5 meter square frames out of
wood or PVC pipe with string tied across the frame at approx.
10cm intervals to provide a easy sampling grid for students to
use.
Allow students to practice with the grids until they appear to
be familiar with how they are used and the types of data they
can collect.
- Students will now be asked to examine two different environments
around their home, in vacant fields, or in city park areas using
the same techniques. They should start with identification of
two sites, explanation about why they are different (degree of
shade, proximity to house, road, trees, shrubs, degree of cultivation,
amount of foot traffic, etc.) and formulation of a hypothesis
related to the comparison of the two sites. They will then collect
data as carefully as possible, but without very specific instructions
about how when to sample, how often to sample, where to sample.
They will use the data to produce a written report related to
their hypothesis with the following parts:
- Title
- Introduction
- Procedure
- Data
- Analysis and Conclusion
The work will be done at home following the initial explanation,
and can be due from 1-2 weeks after assignment.
Safety:
- Be careful.
- Teachers and students should always exercise appropriate safety
precautions and utilize appropriate laboratory safety procedures
and equipment when working on science performance tasks.
Extensions/modifications:
- Students may wish to extend this procedure to examine other
areas such as nearby riparian zones (contrasting those in city
parks to those in rural or wild-land areas), forests (managed
wooded lot vs. wild-land), or wetlands.
|