that the insect is not lost if it leaves the arena. Minimally, one
student should corral the insect with the file folder and stimulate it to jump using the paintbrush, and one should record
the data points. Other students can help corral and keep an
eye on the insect. With multiple observers, there is less of a
chance that the insects’ movements will be missed.
5. A note on recording data points:
Example Discussion Questions
b. Walking insects: These data can be recorded two ways,
either in discrete time increments (the location is
recorded every 10 seconds) or the location is recorded
whenever the insect stops moving. This should be
decided before testing begins and with the nature of
the insect in mind.
1. After completing the first experiment (either the first replication of the basic experiment or the first treatment of the
advanced experiment), did you learn or observe anything
that helped you with the rest of the experiment?
2. Is the behavior of the insect different when there is no stimulus versus when there is a stimulus, either tactile or a physical modification of the arena?
3. How could human error affect the results of the experiment?
(Hint: Think of the stimulus you applied. Was it exactly the
same each time? How can you alter the experiment to make
the stimulus identical every time?)
4. Based on your measurements, how many jumps (or how
long) would it take for the tested insect to move 1 m? 1 km?
5. Is there a relationship between the insect’s average body
length and average jump distance?
6. Do you think a good biocontrol agent disperses quickly or
7. Create a graph to visualize the relationships within your data.
For instance, compare insect types with the average distance
traveled, or compare the average distance traveled to the type
of stimulus used.
Biological control is based on the idea that a specialized natural
enemy of an invasive species can control populations of the invasive species in its adventive range. Most invasive species are spread
by humans and often must get to the point that they are adversely
affecting the invaded habitat before any management steps are
taken to control them. By the time biological control agents are
found, tested, and released, the invasive species has significantly
impacted native species and altered the native habitat (McFadyen,
1998). This case study serves as an introduction to how scientists
are identifying problems and researching solutions to them.
This biological control case study aligns with middle school
level NGSS (Table 5). The advanced experiment integrates with
the science and engineering practices of analyzing and interpreting
data and connects the students with the nature of science through
the use of the scientific method. Students are encouraged to graph
their data, and this integrates the crosscutting concept of patterns.
Table 5. Next Generation Science Standards
covered by this experiment.
Disciplinary Core Area Within This Activity
Relationships in Ecosystems
Biological control agents rely
on their host plants for
sustenance and often exert
pressure on them.
LS4.D: Biodiversity and
Practices Within This Activity
Many invasive plant species are
spread by humans. In the case
of water hyacinth, these plants
can affect the biodiversity of a
habitat by pushing out native
species and impeding human
use of the area by blocking
navigation and water control
MS-LS2-4: Construct an
argument supported by
empirical evidence that
changes to physical or
biological components of an
Invasive species alter
habitats, affecting native
plant and animal
populations. In turn,
biocontrol agents can affect
their target invasive species
competing design solutions
for maintaining biodiversity
and ecosystem services.
Biological control agents are
used in addition to other
control methods to manage
Science and Engineering
Within This Activity
Analyzing and Interpreting
Crosscutting Concepts Within This Activity
Students can analyze and
interpret their data to accept
or reject their hypothesis
and to make additional
observations about the
Patterns Students can create a graph
to visualize their data.
Influence of Science,
Technology on Society and
the Natural World
Students can infer dispersal
time and distance based on
the patterns of movement
and behavior they observed
in their insects.