Download Lesson Overview - University of Wyoming

Nature’s Laboratory: Ecology in Your Backyard
and Beyond
Developed by the University of Wyoming Science Posse
Grade Level: 7-8
Topics Covered: Diversity of Organisms
Behavior and Adaptation
Interrelationships of Populations and Ecosystems
Standards and Benchmarks:
This lesson plan includes topics covering the following Wyoming Science
Academic Content Standards for Grade Span 5-8:
CONTENT STANDARD 1. CONCEPTS AND PROCESSES
In the context of unifying concepts and processes, students develop an
understanding of scientific content through inquiry. Science is a dynamic
process; concepts and content are best learned through inquiry and
investigation.
ACADEMIC CONTENT STANDARD 1. CONCEPTS AND PROCESSES
Students learn about scientific content through inquiry.
8.A.S.1.1 Students relate different organ systems with their specialized function.
8.A.S.1.3 Students describe interconnectedness of diverse organisms within an
ecosystem.
CONTENT STANDARD 2. SCIENCE AS INQUIRY
Students demonstrate knowledge, skills, and habits of mind necessary to safely
perform scientific inquiry. Inquiry is the foundation for the development of
content, teaching students the use of processes of science that enable them to
construct and develop their own knowledge. Inquiry requires appropriate field,
classroom, and laboratory experiences with suitable facilities and equipment.
ACADEMIC CONTENT STANDARD 2. SCIENCE AS INQUIRY
8.A.S.2.1 Students use science reference materials to answer science questions
and present findings.
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8.2 Students use inquiry to better understand the world in which they live.
8.A.S.2.2.a Students ask questions about objects, organisms, or events in the
environment.
8.A.S.2.2.b Students conduct a simple investigation using simple technology and
tools to collect and organize data.
8.A.S.2.2.c Students communicate results of an investigation and match
connections to daily life.
CONTENT STANDARD 3. HISTORY AND NATURE OF SCIENCE IN PERSONAL AND
SOCIAL DECISIONS
Students recognize the nature of science, its history, and its connections to
personal, social, economic, and political decisions. Historically, scientific events
have had significant impacts on our cultural heritage.
ACADEMIC CONTENT STANDARD 3. HISTORY AND NATURE OF SCIENCE IN
PERSONAL AND SOCIAL DECISIONS
Students use scientific knowledge to make personal decisions.
8.A.S.3.2.a Students identify and perform a task associated with a local problem
regarding natural resources.
Overview of Lessons:
Lesson Plan 1: Habitat Is Where the Heart Is
- Introduction to animals and their habitats
- Use of field equipment to study animal-habitat relationships
- Development of Environmental Impact Assessment
Lesson Plan 2: Food Webs in the Backyard and Beyond
- Introduction to food webs and trophic levels
o Producers, consumers, decomposers
- Description of backyard food webs
- Introduction to adaptation and biomes
- Comparison of skull and track features with biomes
- Additional Options
o Keystone species
o Discussion of invasive species effects
Lesson Plan 3: Predator or Prey: Who’s in Control?
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Introduction to population growth
o Exponential vs. logistic growth
o Predator-prey population cycles
o Top-down vs. bottom up effects
Working with data
o Predator-prey data
o Tree-ring data
Discussion of what drives population cycles
Notes: The lessons contained in this unit could be used as stand-alone lessons to
supplement material covered in class. Alternatively, they could be used
sequentially. The lessons are meant to cover ecology at levels from the
individual to the ecosystem. Though these fields of ecology are present in all 3
lessons, Lessons 1 and 2 focus more heavily on community and ecosystem
ecology, while Lesson 3 leans more towards population ecology.
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Lesson Plan 1: Habitat Is Where the Heart Is
Estimated Time: 80 minutes
Objectives (Enduring Ideas):
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Students will learn how scientists study an animal’s relationship with its
environment – this is the definition of the field of ecology
Students will learn what makes up an animal’s habitat requirements
Students will learn how animals are adapted to their environment
Students will learn how to use radio telemetry as a method in wildlife
research
Students will learn how to identify local animal species from their tracks
Students will learn that animals are differentially affected by humaninduced changes to habitats
Vocabulary:
Biodiversity: a measure of diversity that increases with species evenness and
species richness (also “species diversity”)
Community: all of the living organisms living in a specific area
Digitigrade: walking on your toes
Ecosystem: a biological community plus all of the abiotic (non-living) factors
influencing that community.
Habitat: the arrangement of food, water, shelter or cover, and space suitable to
animals’ needs
Habitat generalist: a species that can survive in many types of habitats
Habitat fragmentation: the conversion of once continuous tracts of habitat to
smaller, interrupted patches
Habitat specialist: a species that requires a specific type of habitat to survive
Plantigrade: walking on the soles of your feet
Population: a group of individuals of a single species inhabiting a specific area
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Shannon-Wiener Index: a quantitative index of species diversity (see Molles 2008
for equation)
Species evenness: the relative abundance of species in a community
Species richness: the number of species in a community
Materials and Preparation:
 PowerPoint presentation on animals and habitat (Appendix 1)
 Radio telemetry equipment (may be available from local Game and Fish
office)
 Thermometer
 Animal tracking guide books
 Data sheets for habitat descriptions (Appendix 2)
 Clipboards to record data
 Rubber animal tracks for making tracks in soil or snow (Available online
through Acorn Naturalists)
 Stuffed/plastic animals or flash cards
Lesson Overview:
Part1:
o Habitat Selection Background
 Briefly discuss of how we can learn what habitats animals use
Part2:
o Search for different animals with telemetry and tracking
 Split students into teams and locate transmitters
attached to different “herds/groups” of animals
 Other groups of students will locate animals based on
track imprints in the soil
 Have students write up habitat descriptions for each
animal
Part3:
o Discuss potential human effects on habitat loss and which of our
study animals is most likely to be affected by habitat loss
 Work though a problem set
Background Information: (for teachers)
This activity involves considerable set-up time before class. The main idea
is that different species of animals are connected with different environments.
In this lesson, students will locate animals in their corresponding habitat types.
Some species will be habitat generalists (e.g., deer) and will be found in more
than one habitat. Other species (e.g., marten) will be habitat specialists. You
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will need to place the stuffed/plastic animals, with transmitters attached, in
several habitat-types. For example, a plastic mountain lion w/ transmitter could
be hidden in a wooded area and deer w/ transmitters in wooded and meadow
area. In addition, if there aren’t wild animal tracks in the area, then rubber
tracks should be imprinted into the dirt. The teacher should make note of where
the tracks and transmitters are located so they can find them later if the
students can’t!
This lesson plan is probably best done after students have covered
concepts such as ecosystems and food webs in the classroom. General
ecology books such as Molles 2008 provide information on these concepts. This
is especially important for Part 3 so they can make predictions about what might
happen to a predator if one of its prey sources is depleted.
Procedures:
I.
Engage
Show PowerPoint presentation (Appendix 1) on how to determine an animal’s
preferred habitat.
 Discuss with students some potential methods for studying wildlife/habitat
relations
 Following the presentation, give the students instructions for the outdoor
portion of the activity. Tell them that they will look for several wildlife
species by using radio telemetry (from an airplane) and by looking for
tracks on the ground.
II.
Explore/Explain
How do we tell animals’ preferred habitat
 Students will go outside. This could be a schoolyard, a city park,
wilderness area, etc.
 Part1: Put students into groups of 2-3. Some groups will “fly” and look for
animals with radio telemetry gear. These students will search for and
locate transmitters attached to plastic animals. Other groups will look for
tracks and identify the animal with an animal tracking field guide.
 Part2: Have students use a habitat evaluation form (Appendix 2) to
evaluate which species are found in which habitat. On this worksheet,
“overstory” refers to all the coniferous and deciduous tree species in the
habitat while “understory” refers to the plants growing beneath this tree
canopy. In the “notes” section the students can write any other
observations they make that they might think are interesting about the
habitat they’re describing. Explain to the students that this type of
worksheet is similar to habitat evaluation forms that scientists use in real
wildlife research.
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III.
Elaborate
Ask which animal species will be most impacted by a development project in a
particular habitat type (make Environmental Impact Assessment) or by impacts
to other species in the food web.
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Have students return to the classroom. While remaining in their groups,
give them a worksheet (Appendix 3) and tell them to evaluate the impact
of alterations to their study ecosystem. Scenario 1 should be used when
more time is available (approximately 15 minutes), while scenario 2 can
be completed more quickly. In scenario 1, tell them that a grocery store is
being planned for the forested portion of their study ecosystem. Recall
that the students’ study area encompasses several habitat types, only one
of which is forested. The students will need to develop an Environmental
Impact Assessment to determine which species are most likely to be
affected by the removal of forest. In scenario 2, a disease, such as
chronic wasting disease, has begun to spread within the deer population.
Ask the students to determine which other animal species are likely to be
impacted by changes to the deer population. In this way the students
are reminded that habitat includes food, so the predators may be
impacted by disease in deer. If time allows, students can work through
both scenarios.
IV.
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Have students will present their opinions on scenario 1 and/or 2 to
classmates.
Students will turn in worksheet (Appendix 3) with their answers to scenario
1 and/or 2.
V.
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Evaluate
Enrichment
If time allows, this lesson would be an ideal place to introduce the
concept of biodiversity. Numbers of “animals” could be varied within
each habitat type, and students could be asked to calculate species
richness and evenness for each community. This would require that
students be familiar with the distinction between “population” and
“community”. A measure, such as the Shannon-Weiner Index (Molles
2008), could be used to compare species diversity between the different
habitats.
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References:
Vocabulary
Council for Environmental Education. 2004. Project Wild: K-12 Curriculum &
Activity Guide. Council for Environmental Education, Houston, TX.
Molles, M. C. 2008. Ecology: concepts and applications, 4th Edition. McGraw-Hill,
New York.
Acknowledgments:
The use of telemetry equipment to find transmitters was adapted from a
laboratory taught by Merav Ben-David and Elizabeth Flaherty in their Wildlife
Ecology course at the University of Wyoming.
The application of habitat data to an EIA was adapted from Karin Westerling’s
“Design an Ecosystem” lesson:
http://www.accessexcellence.org/AE/ATG/data/released/0079KarinWesterling/index.php
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Lesson Plan 2: Food Webs in the Backyard and Beyond
Objectives (Enduring Ideas):
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Students will learn about producers, consumers, and decomposers
Students will learn about the interconnectedness of ecosystems
Students will learn about adaptation, and specific adaptations animals
have to their environment
Students will learn about keystone species (if enrichment portion is used)
Students will learn about the potential effects of invasive species
Vocabulary:
Adaptation: a trait that increases the ability of an individual to survive and
reproduce compared with individuals without the trait
Biome: usually large areas distinguished by their predominant plants and
associated with particular climates
Carnivore: an animal that consumes other animals.
Consumer: organisms that obtain energy by consuming other organisms.
Decomposer: a consumer that gets its energy from the remains and waste
products of organisms. A detritivore.
Ecosystem: a biological community plus all of the abiotic factors influencing that
community.
Food web: a complex model of interconnected food chains in which there are
multiple links between species.
Herbivore: an animal that eats only plants.
Keystone species: species that, despite low biomass (or abundance), exert
strong effects on the structure of the communities they inhabit.
Omnivore: an animal that has the ability to eat and survive on both plant and
animal products.
Producer: an organism, such as a plant, that converts light energy to chemical
energy. An autotroph.
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Trophic level: each feeding level in a food chain.
Materials and Preparation:
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Skulls and tracks of several mammals (may be available at local Game
and Fish office or through natural history museums)
PowerPoint slides of different biomes
Rubber animal tracks for making tracks in soil or snow (available online
through Acorn Naturalists)
Soil sampling kit (Available online through Carolina Biological)
Compound and dissecting microscopes
Flash cards of different plants, animals, fungi, etc. in Wyoming
Lesson Overview:
Part1:
o Use PowerPoint slides (Appendix 4) to discuss ecosystems and food
webs
o Define biotic and abiotic factors (also introduced in Lesson 1)
Part2:
o Construction of food webs
 Have students go outside and catalogue all the living
organisms they can find.
 If weather doesn’t permit, give students flash cards with
different Wyoming species.
 Define producer, consumer, and decomposer.
 Have students construct food webs for the organisms
they catalogued or were given as cards.
Part3:
o Use of skulls to describe adaptation to the environment
 Have students examine features of skulls and tracks.
They’ll try to group animals together that appear similar
(for example carnivores, herbivores, etc.)
 Have students define each study specimen as an
herbivore, carnivore, or omnivore.
 Students will also be shown different biomes and asked
to assign skulls to the correct one.
Background Information: (for teachers)
The second part of this lesson would best be done after the students have
learned about evolution by natural selection in the classroom. Otherwise the
concept of adaptation may be difficult to grasp. The Brooker et al. (2008) text
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shown in the references section provides a good resource to the teacher for this
information. This lesson could easily be split into two 45 minute class periods. In
this first part, students develop food webs and classify organisms as producers,
consumers, and decomposers. In the second part, students look at actual
adaptations that some of these organisms have that put them in such
categories. If students go outdoors but find few organisms, collecting soil
samples and examining them under a microscope may give them additional
organisms to add to their food webs. The same idea goes for making tracks with
the rubber casts. Students could identify the tracks and add these species to
their food webs.
During the skull lab, the teacher can vary the number of skulls that the
students look at based on available time. It would be useful to have a few skulls
from the same family so that students can group them together (e.g., bobcat
and mountain lion skulls). There should at least one skull each representing an
herbivore (e.g., elk), carnivore (e.g., wolf), and omnivore (e.g., black bear).
Pictures of different ecosystems should coincide with the available skulls (e.g,
desert, ocean, forest, mountain).
Procedures:
I.
Engage
PowerPoint presentation (Appendix 4) on food webs and the difference
between a population, community, and ecosystem.
 Ask students to differentiate between the level of population, community,
and ecosystem. When it is clear that they understand what a community
is they will move to the outdoor portion of the lesson.
II.
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Explore/Explain
Part 1: Get students into pairs. Each pair will have 10 minutes to write
down all the living creatures they can find in their schoolyard, local city
park, etc. Encourage students to include organisms such as fungi. If time
permits, students can take soil samples for analysis of microscopic
organisms in the classroom.
Part 2: Have students return to the classroom and create a food web from
their lists.
Part 3: Ask thee students to think of useful ways that these organisms could
be classified. At this point list the definitions of producer, consumer, and
decomposer (Appendix 4).
Part 4: Ask students to classify the organisms in their food webs as
producers, consumers, and decomposers. At this point the food webs
can be turned into concept maps as the students add the action that
each species is having on its adjacent member in the food web. For
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example, an arrow would be drawn from a plant to an herbivore. Along
this arrow will be written the interaction happening along this arrow (for
example “herbivore eats plant and gets energy from the plant”).
III.
Elaborate
The next part of the lesson involves examining mammal skulls, skins, and tracks.
This should be left for a second class period if classes are only 45-50 minutes.
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Ask students to describe which members of their food webs are
herbivores, carnivores, or omnivores. Then tell them that where a species
fits into a food web is partially determined by adaptations it has for
feeding. At this point give the definition of “adaptation”.
Discuss with the students the difference between a carnivore, herbivore,
and omnivore.
Ask students to form pairs and rotate through stations that contain
mammal skulls, skins, and imprints of tracks placed at the back of the
room. In addition, pictures of different types of biomes will be given.
Have students answer questions from a worksheet (Appendix 5).
After students correctly identify all the specimens, have them evaluate
the range of the different species with Google Maps.
End this lesson with a discussion of what allows some species to have
larger/smaller ranges. For example, animals that are adapted to live in
old growth forests are unable to live in newly planted forests.
IV.
Evaluate
Rubric
 There should be an open discussion of the answers to the worksheet. Then
collect the students’ concept maps and/or worksheets from the skull
identification lab.
VI.
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Enrichment
If time allows, the concept of a “keystone species” could be introduced.
Appendix 4 has slides showing a classic example of a keystone species,
the seastar Pisaster. The keystone species concept was developed by
Paine (1969). In rocky intertidal zones, Pisaster is a major predator of the
mussel Mytilus californianus. When the predator is removed the mussels
overtake the shoreline. When the seastar is present it keeps the mussels in
check and allows other species to flourish.
Once students understand this concept they can brainstorm to think of
other potential keystone species. A famous local example is wolves
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keeping ungulate herds in check and potentially reducing herbivory on
plants.
References:
Vocabulary
Brooker, R. J., E.P. Widmaier, L.E. Graham, and P.D. Stiling. 2008. Biology.
McGraw-Hill, New York.
Molles, M. C. 2008. Ecology: concepts and applications, 4th Edition. McGraw-Hill,
New York.
Keystone species
Paine, R.T. 1969. A note on trophic complexity and community stability.
American Naturalist 103: 91–93.
Power, M. E., D. Tilman, J. A. Estes, B. A. Menge, W. J. Bond, L. S. Mills, G. Daily, J.
C. Castilla, J. Lubchenco, and R. T. Paine. 1996. Challenges in the quest for
keystones. Bioscience 46:609-620.
Acknowledgments:
The use of skulls in this lesson plan was adapted from Elizabeth Flaherty’s What Is
Alive?: http://www.scienceposse.org/displayfaculty.asp?facultyid=2170
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Lesson Plan 3: Predator or Prey: Who’s in Control?
Grade Level: 7-8
Estimated Time: 45 minutes
Objectives (Enduring Ideas):
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Students will learn about predator/prey cycles
Students will learn about bottom-up and top-down forces in food chains
Students will learn how tree rings can be used to study fluctuations in
environmental conditions
Students will hone basic graphing skills
Vocabulary:
Bottom-up forces: Regulation of food-web components by either primary
producers or the input of limiting resources (e.g., nutrients, space).
Predator: a heterotrophic organism that kills and eats other organisms for food.
Usually an animal that hunts and kills other animals for food.
Top-down forces: Regulation of lower food-web components by an upper-level
consumer.
Trophic cascade: Reciprocal predator-prey effects that alter the abundance,
biomass or productivity of a population, community, or trophic level across more
than one link.
Materials and Preparation:
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Tree increment borer (available from Forestry Suppliers or local Forest
Service office)
ruler
Tree cores
Paper simulations of tree-rings
Data with numbers of wolves and moose on Isle Royale from 1950-2000.
Computer with Microsoft Excel
Lesson Overview:
Part1:
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o Discuss how historical records can tell us about long-term ecological
changes
o Discuss what factors drive populations of predators and prey
o Discuss how tree rings can be used to reconstruct past
environmental conditions
Part2:
o Examine population data and tree rings
 Students will examine real tree rings
 Students will count tree rings from strips of paper
designed to simulate real trees
 Students will compare these to predator and prey
population data
Part3:
o Enrichment
 Discuss what might drive these cycles – abiotic factors,
predators, prey? Or a combination?
Background Information: (for teachers)
Teachers should read McLaren and Peterson (1994). This paper describes a
long-term study on Isle Royale National Park. Populations of wolves and moose
have fluctuated for several decades, and there are 2 competing hypotheses as
to what drives these cycles. The bottom-up hypothesis says that plant growth is
limited by climate, thereby limiting forage available to moose. The availability of
moose then determines the number of wolves. The top-down, or trophic
cascade, hypothesis says that wolf predation on moose depresses moose
numbers and releases plants from herbivory. In addition, a lesson plan designed
for undergraduate college students is available online that makes use of this
case study: http://ublib.buffalo.edu/libraries/projects/cases/Isle.html
In this lesson, students will be given several decades of census data on the
wolf and moose population on Isle Royale. They will graph these data. Then the
students will measure tree-ring widths from balsam fir trees on the island. These
data will be compared with the graphs for the moose and wolves to evaluate
which of the competing hypotheses is best supported. There is a great deal of
information on tree rings and tree ring research at the “Ultimate Tree Ring Web
Pages” http://web.utk.edu/~grissino/.
Procedures:
I.
Engage
Give PowerPoint presentation (Appendix 6) on what controls population growth.
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Ask students about factors that control population growth. It is likely that
someone will come up with predation, but if not, introduce this as one
factor. Tell them that predation will be the topic today.
Introduce students to the idea of top-down vs. bottom-up forces in food
webs (see vocab and Appendix 6).
Give students a brief background on the ecology of Isle Royale National
Park. They will be informed that the park has a unique long-term record of
wolf and moose populations.
II.
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Explore/Explain
Part1: Have students form pairs. Give each pair data on wolf and moose
numbers, from 1950-2000.
Part 2: Give students graph paper and ask them to decide on which axes
to put numbers vs. time.
Part 3: Show students how an increment borer works. For a picture
demonstration see: http://www.cnr.vt.edu/dendro/forsite/incre.htm. Then
examine a real tree core and discuss how rings form. Rings form due to
variation in the rate of growth with changing seasons.
Part 4: Give students a strip of paper that simulates ring widths on a tree
and will count these widths from 1950-2000.
Part 5: Have students compare graphs from wolves and moose with tree
ring data.
III.
Elaborate
Discuss what the driving force is in these cycles. In the end the students will see
that the answer varies depending on densities of moose, wolves, or climate
factors.
IV.
Evaluate
Rubric
 Collect students’ graphs and discussion of predator/prey cycles.
References
Fortier, G. M. 2000. The wolf, the moose, and the fir tree. Journal of College
Science Teaching 30:92-95.
McLaren, B. E., and R. O. Peterson. 1994. Wolves, moose, and tree rings on Isle
Royale. Science 266:1555-1558.
Molles, M. C. 2008. Ecology: concepts and applications, 4th Edition. McGraw-Hill,
New York.
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Pace, M. L., J. J. Cole, S. R. Carpenter, and J. F. Kitchell. 1999. Trophic cascades
revealed in diverse ecosystems. Trends in Ecology & Evolution 14:483-488.
Power, M. E., D. Tilman, J. A. Estes, B. A. Menge, W. J. Bond, L. S. Mills, G. Daily, J.
C. Castilla, J. Lubchenco, and R. T. Paine. 1996. Challenges in the quest for
keystones. Bioscience 46:609-620.
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