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GRADE LEVEL: 9-11

TIME ALLOTMENT: Three 45-minute periods

OVERVIEW: This inquiry-based lesson plan will challenge students to design and conduct scientifically valid experiments to evaluate hypotheses regarding an animal’s expected behavior in response to changes in its environment.

Students will first view and analyze video segments from the NATURE film “Earth Navigators” as they begin to think about animal behavior as a response to stimulus in the environment. The video clips feature many different animal species reacting to changes in the environment by migrating from one part of the earth to another. Students will predict the reasons for these migrations and will determine the stimuli that actually trigger the animals to migrate.

Following the video exploration, students will conduct reading and research to learn about isopods (commonly known as pill bugs or roly polies). The students will use the information they gather to formulate research questions having to do with the isopods’ expected response to environmental stimulus. The students will design experiments that can be conducted in the classroom to test their hypotheses. They will conduct the student-designed experiments, collecting data and reporting their findings and conclusions. They will also make suggestions for future improvements in the experimental protocol.

SUBJECT MATTER: Living Environment/Biology

LEARNING OBJECTIVES:

Students will be able to:

• Draw connections between the migratory behavior of different animals and seasonal changes on Earth;
• Describe migration as an instance of behavioral response to stimulus;
• Using anatomical and environmental information, create a research question about an isopod’s behavior in response to environmental stimulus;
• Create a hypothesis that addresses the research question;
• Design and conduct an experiment to evaluate the hypothesis;
• Collect data from the experiment, describe results, and evaluate conclusions.

STANDARDS AND CURRICULUM ALIGNMENT:

CONTENT STANDARD A: As a result of activities in grades 9-12, all students should develop:

• Abilities necessary to do scientific inquiry
• Understandings about scientific inquiry

CONTENT STANDARD C: Life Science. As a result of activities in grades 9-12, all students should develop understandings of:

• Behavior of Organisms.

New York State Regents Core Curriculum Alignments
Living Environment Core Curriculum
STANDARD 1: Students will use mathematical analysis, scientific inquiry, and engineering designs, as appropriate, to pose questions, seek answers, and develop solutions

Key Idea 2: Beyond the use of reasoning and consensus, scientific inquiry involves the testing of proposed explanations involving the use of conventional techniques and procedures and usually requiring considerable ingenuity.

Performance Indicator 2.1: Devise ways of making observations to test proposed explanations.

Performance Indicator 2.3: Develop and present proposals including formal hypotheses to test explanations; i.e., predict what should be observed under specific conditions if the explanation is true.

Performance Indicator 2.4: Carry out a research plan for testing explanations, including selecting and developing techniques, acquiring and building apparatus, and recording observations as necessary.

Key Idea 3: The observations made while testing proposed explanations, when analyzed using conventional and invented methods, provide new insights into natural phenomena.

Performance Indicator 3.1: Use various methods of representing and organizing observations (e.g., diagrams, tables, charts, graphs, equations, matrices) and insightfully interpret the organized data.

STANDARD 4: Students will understand and apply scientific principles and theories pertaining to the physical setting and living environment and recognize the historical development of ideas in science.

Key Idea 5: Organisms maintain a dynamic equilibrium that sustains life.

Performance Indicator 5.3: Relate processes at the system level to the cellular level in order to explain dynamic equilibrium in multicelled organisms.

5.3a Dynamic equilibrium results from detection of and response to stimuli. Organisms detect and respond to change in a variety of ways both at the cellular level and at the organismal level.

Key Idea 6: Plants and animals depend on each other and their physical environment.

Performance Indicator 6.1: Explain factors that limit growth of individuals and populations.

6.1f Living organisms have the capacity to produce populations of unlimited size, but environments and resources are finite. This has profound effects on the interactions between organisms.

MEDIA COMPONENTS

Video

NATURE: Earth Navigators, selected clips

Clip 1: “Planetary Moves”

Introduction to four species’ migratory patterns.

Clip 2: “Monarch Migration”

The start of the monarch butterfly’s northward trek.

Clip 3: “Hungry Beasts”

Wildebeest and locusts on the move.

Clip 4: “Arctic Summer”

Many birds summer in the arctic.

Access the streaming and downloadable video segments for this lesson at the Video Segments Page.

Web Sites

FOSSWEB: Isopods
Includes general information on isopods and useful tips on how to find and keep pill bugs for the classroom

Isopod, Pillbug, Sow bug information
Includes general information on isopods

NCES Graphing Tutorial
This tutorial from the National Center for Education Statistics explains the various kinds of graphs and demonstrates how to build them.

MATERIALS

For the classroom:

• Computer and projection system for showing video clips
• Several computers for student use
  Chalkboard or whiteboard
• Isopods (pill bugs) in a terrarium or other classroom habitat (enough specimens for at least 15-20 per student group)
• Isopod Research Organizer Answer Key (PDF) (RTF)

Materials to be used in pill bug experiments (several of each):

• Paper towels or filter paper
• Eye droppers
• Portable Lamps
• Heat Packs
• Cold Packs
• Card stock or construction paper
• Substrate materials, e.g. sand, gravel, dirt, shredded paper, bark, etc.
• Thermometers

Per group of 3-4 students:

• Stopwatch
• Materials to make “test chambers”: Petri dishes or small disposable bowls or plates – enough for approx. 5 or 6 per group
• Roll of masking tape
• Scissors or art knife
• Paper cup
• Data Collection Chart
• Graph paper

Per student:

• Isopod Research Organizer (PDF) (RTF)
• Isopod Experiment Organizer (PDF) (RTF)
• Isopod Experiment Assessment Rubric (PDF) (RTF)
• Paper and pen

PREP FOR TEACHERS

Prior to teaching this lesson, you will need to:

Preview all of the video clips and Web sites used in the lesson.

Download the video clips used in the lesson to your classroom computer, or prepare to watch them using your classroom’s Internet connection.

Bookmark the Web sites used in the lesson on each computer in your classroom. Using a social bookmarking tool such as del.icio.us or diigo (or an online bookmarking utility such as portaportal) will allow you to organize all the links in a central location.

Procure live isopods (pill bugs) for the students to observe and use. Isopods are very easy to care for in the classroom, and can either be collected in the wild or ordered from a biological supply company. For more information on collecting, rearing, and keeping isopods in the classroom, see the two Isopod references mentioned in the “web sites” section.

Familiarize yourself with accepted guidelines for the safe and responsible handling of live animals in a classroom setting. The NSTA’s Responsible Use of Live Animals and Dissection in the Science Classroom and the Institute for Laboratory Animal Research’s Principles and Guidelines for the Use of Animals in Precollege Education are good general resources. Also check to see if your state or district has special animal handling guidelines or requirements.

Make copies of the Isopod Research Organizer and the Isopod Experiment Organizer for each student.

Next: Proceed to Activities

Background:
Seasonal changes impel a wide variety of creatures to begin migrations – sometimes on an epic scale – to feeding, mating, and breeding grounds. These journeys sometimes cover thousands of miles and require ingenious methods to accomplish. These video segments from the NATURE film “Earth Navigators” feature different animal species reacting to changes in their environments by migrating from one part of the earth to another.

Suggested Focus Questions:

Clip 1: Planetary Moves

1. What causes the seasons?
2. How does the earth’s travel around the sun relate to the movements of animals around the globe?
3. Name the four migrating animals in this clip. Where on the globe does each animal migrate?

Clip 2: Monarch Migration

1. How is the spring equinox defined?
2. What does the coming of spring trigger for monarch butterflies?
3. Where does the monarch’s migration begin? Where are they headed?

Clip 3: Hungry Beasts

1. Why do wildebeest migrate? Why do locust hoppers migrate? How is the migration of the two animals similar?
2. How many wildebeest might there be in a typical herd? Why do you think the wildebeest travel in such large groups?
3. Locate the Serengeti and Lake Victoria on a world map. Use the map to trace the wildebeest’s annual migratory path.

Clip 4: Arctic Summer

1. Define the summer solstice. What conditions can you expect above the Arctic circle in summer?
2. Why do so many birds spend the summer in the Arctic?

Downloadable QuickTime versions of the video segments:
(Note: To downoad a video, right-click on the video title and click “Save Link As…” or “Save Target As…” On a Mac, press the CTRL key and simultaneously click the mouse, then save the link.)

Clip 1: “Planetary Moves”

Clip 2: “Monarch Migration”

Clip 3: “Hungry Beasts”

Clip 4: “Arctic Summer“

Producer: Ronnie Godeanu
Art Director: Sabina Daley
Graphic Art: Lenny Drozner
Writer: David Malakoff
Technical Director: Brian Patrick Lee
Scientific Consultant: Gianna Savoie

Thirteen Online is a production of Thirteen/WNET New York’s Kravis Multimedia Education Center in New York City. Anthony Chapman, Director of Interactive & Broadband. Carmen DiRienzo, Vice President and Managing Director, Corporate Affairs.

© 1998 Thirteen/WNET New York

All Rights Reserved

Television Credits

A Co-Production of Thirteen/WNET New York and BBC-TV

Funder Credits

Funding for the TV series NATURE is made possible in part by Park Foundation. Major corporate support is provided by Canon U.S.A., Inc., Ford Motor Company, and TIAA-CREF. Additional support is provided by the nation’s public television stations.

For those interested in the subjects shown on SECRET GARDEN, we present the following Web sites. All links are valid as of December 21, 2000.

Biggs Wildlife Pond
http://www.sonic.net/~bigsnest/Pond/
Learn about the pond that Kathy and Dave Biggs created in their backyard and see pictures of the plants and animals it supports.

The Butterfly Zone
http://www.butterflies.com/
Tips on how to start your own butterfly garden, with links to a butterfly identification guide and the story of one man’s garden.

The Backyard Wildlife Habitat Program
http://www.nwf.org/backyardwildlifehabitat/
The National Wildlife Federation provides a wide array of resources for creating backyard habitats and understanding the plants and animals that live in them.

Smithsonian Butterfly Habitat Garden Homepage
http://www.si.edu/gardens/butterfly/
Extensive site detailing butterfly garden do’s and don’ts, as well as fascinating insights into the natural history of butterflies and plants.

Seed Savers Exchange
http://www.seedsavers.org/Home.asp
Web site of the organization that protects heirloom seeds, which can also be reached at the following address: Seed Savers Exchange, 3076 North Winn Road, Decorah, IA 52101.

Green Landscaping With Native Plants
http://www.epa.gov/greenacres/
Extensive site with practical advice from the U.S. Environmental Protection Agency.

Print Resources

For those interested in the secret life of the garden and gardening, we recommend the following books.

Bodanis, David. THE SECRET GARDEN: DAWN TO DUSK IN THE ASTONISHING HIDDEN WORLD OF THE GARDEN. New York: Simon & Schuster, 1992.

Capon, Brian. BOTANY FOR GARDENERS: AN INTRODUCTION AND GUIDE. Portland, Oregon: Timber Press, 1992.

Conrad, Jim. DISCOVER NATURE IN THE GARDEN: THINGS TO KNOW AND THINGS TO DO. New York: Stackpole Books, 1996.

Daniels, Stevie. THE WILD LAWN HANDBOOK. New York: Macmillan Publishing Co., 1995.

Druse, Ken, and Margaret Roach. THE NATURAL HABITAT GARDEN. New York: Crown Publishing Group, 1994.

Kress, Stephen W. THE BIRD GARDEN. London: Dorling Kindersley, 1995

Rogers, Marc, and Polly Alexander. SAVING SEEDS: THE GARDENER’S GUIDE TO GROWING AND STORING VEGETABLE AND FLOWER SEEDS. New York: Garden Way, 1991.

Schneck, Marcus. YOUR BACKYARD WILDLIFE GARDEN. New York: Rodale Press, 1992.

Schultz, Warren. THE CHEMICAL-FREE LAWN. New York: Rodale Press, 1989.

Stein, Sara Bonett. PLANTING NOAH’S GARDEN: FURTHER ADVENTURES IN BACKYARD ECOLOGY. New York: Houghton Mifflin, 1997.

Swain, Roger. EARTHLY PLEASURES: TALES FROM A BIOLOGIST’S GARDEN. New York: Lyons Press, 1994.

Tufts, Craig, and Peter Loewer. THE NATIONAL WILDLIFE FEDERATION’S GUIDE TO GARDENING FOR WILDLIFE. New York: Rodale Press, 1995.

Xerces Society Staff. BUTTERFLY GARDENING. San Francisco: Sierra Club Books, 1990.

Many plant varieties are disappearing.

In addition to providing havens for wildlife, backyard gardeners can also play an important role in saving some plant varieties from extinction. Over the last few centuries, farmers and gardeners have given up many traditional food crop varieties in favor of new, hardier varieties that are easier to grow and ship.
United States, for instance, has shrunk from more than 7,000 to fewer than 2,000 — and less than a dozen types make up the bulk of what is available in stores. Similarly, farmers in North and South America once grew thousands of tomato varieties; today, most have been lost or exist as seeds stored by elderly gardeners.

To save these often tasty and beautiful “heirloom” varieties, an increasing number of dedicated gardeners are growing these threatened plants and sharing the seeds with others. These “seed savers” have rescued hundreds of varieties, including many that are considered culinary superstars. Two leaders of this grassroots conservation movement are Kent and Diane Whaley of the nonprofit Seed Savers Exchange in Decorah, Iowa . The couple founded the Exchange in 1975 after an elderly, terminally-ill relative asked them to safeguard precious garden seeds brought from Bavaria four generations earlier. Today, the Exchange protects more than 13,000 endangered vegetable varieties, 700 old-time apples and 200 hardy grapes.

Plant breeders believe some of these old varieties hold genes that will allow them to create new, tastier crops that resist drought and disease, and require fewer chemicals. So far, 1,000 people across the country have joined the Seed Savers Exchange, using the organization’s newsletter and periodic meetings as a central clearinghouse for sharing information on growing treasured varieties and swapping rare seeds. The group also publishes a catalog and other materials that explain where to find heirloom varieties and how get started in seed saving. To become a conservator yourself, contact the Seed Savers Exchange. A winner of one of the MacArthur Foundation’s “genius grants” for his seed-saving work, Kent Whaley believes that gardeners committed to saving these seeds are providing insurance for the future. “It’s genetic treasure,” he says.

You can easily lure wildlife to your garden.

Growing a garden with plenty of nooks and crannies for critters isn’t that difficult. So says the National Wildlife Federation’s Heather Carskaddan, who has helped create more than 20,000 wildlife-friendly yards through the group’s Backyard Wildlife Habitat Program. “You need four key elements in your garden to attract wildlife,” she explains. “Animals need food, water, cover, and places to raise young.”

To feed the animals, one should plant species that produce flowers, fruits, nectar, nuts, and seeds at different seasons. Be aware that some animals prefer specific plants. Goldfinches, for instance, are attracted to thistles and other seed-bearing flowers, while hummingbirds prefer bright, nectar-rich flowers, such as columbine, bee-balm, and trumpet vine. Butterflies can be particularly picky, says naturalist Craig Tufts of the National Wildlife Federation: “Native butterflies have very limited food preferences, but if you put the right plant out it’s like a beacon.” Monarch butterflies, for instance, prefer laying their eggs on milkweed, because that is what they eat at their caterpillar stage. For gardeners not sure where to start, many commercial suppliers now package seed combinations geared toward attracting butterflies, birds, and even bats.

A water source like a birdbath, dripping hose, or even a puddle can be enough to slake the thirst of birds and butterflies, but if you really want an adventure, Tufts says, build a small pond in your backyard. “It surprises people how fast a water garden is colonized — it’s as if the dragonfly larvae and frogs parachute in,” Tufts says. “You wake up one morning and discover a chorus of breeding toads.” Sometimes, providing good cover for wildlife means being what some people might consider a messy gardener. Cavity-ridden dead trees, brush piles, and tangled bushes can all provide much-needed homes to some species, but too often, gardeners clean them out in favor of a tidy appearance. For those in cold climates, planting evergreens can provide winter shelter not offered by trees and bushes that lose their leaves.

A lawn provides poor cover for most animals.

Carskaddan encourages wildlife gardeners to use plants native to their area. Animals recognize these plants, “and since they are adapted to your region, you can use fewer chemicals and less water” as you garden, she says. She also urges gardeners to reduce both their use of pesticides and the size of their grass lawns as much as possible. “[Lawns] are considered biological deserts because they are single-species monocultures,” she explains. “By getting more creative, you can provide different levels of cover for everything from tiny voles to larger birds.”

Biologists caution that some animals are simply unable to adapt to life around people, such as warblers that require quiet, mature forests or salamanders that need a large, moist habitat. Even the most wildlife-friendly garden won’t be able to attract these creatures. In fact, scientists note that the most common garden life — weeds, crop-eating insects, and birds that thrive near structures — tend to be generalists, able to feed and nest in a wide variety of areas. Some go as far as to call these highly-adaptable organisms “weed species,” because they can thrive almost anywhere. “Weeds” or not, the average gardener generally welcomes the sight of brilliantly-hued cardinals and blue jays feeding in his backyard.

In addition, researchers say, a wildlife-friendly garden can help discourage many unwanted pests, like plant-eating aphids, by attracting the insects’ natural predators. “One of my favorite examples is what can happen when gardeners don’t spray pesticides,” says Tufts, who notes that although chemicals do get rid of unwanted pests like aphids, they also kill the insects’ natural predators, who may do the job more effectively. After gardeners who decide to shun pesticides stop using them, Tufts says, aphid populations may increase at first, “but soon a whole army of predators arrives, from ladybugs and lacewings to serpentflies and mummy wasps. Most people can’t believe that all these things are suddenly eating aphids — and all kinds of other pests, too!” he adds.

Here, the extraordinary lurks just beyond the ordinary — from amorous snails and hedgehogs to ravenous slug-eating beetles, choking creeping vines, and courageous mother bugs. Even seemingly innocent flowers hide lethal, perfectly-camouflaged predators among their folds, eager to snatch an unsuspecting bee from its nectar meal. And that warm, brushy compost pile? It could actually be a nursery for baby snakes, who wait inside their eggs for just the right conditions to slither out. The presence of snakes is just one sign that you’ve got a garden that does more than please the eye: it also provides an important habitat for plants and animals whose original homes may no longer exist.

“When people open their eyes, they can be amazed at what they can find in their own backyards,” says Craig Tufts, Chief Naturalist of the National Wildlife Federation in Vienna, VA and an expert on garden ecology. “If you look closely, you will see things you have never seen before — even though they’ve been there all along,” he explains.

“People often don’t realize what is right outside their doors,” adds Heather Carskaddan, who manages the Federation’s Backyard Wildlife Habitat Program, which encourages people to create yards that are attractive to wildlife. City and suburb dwellers “are disconnected from the landscape,” she believes. “They spend a lot of time in the car and in the house watching TV, instead of out romping around.”

A bit of garden snooping, however, can reveal sights more entrancing than a late-night movie. Fans of Westerns, for instance, may enjoy watching several kinds of common ants as they “wrangle” aphids, herding the tiny sap-sucking insects along plant stems in order to harvest the sweet, dewy nectar that aphids produce as waste. In return for the snack, researchers believe, the ant “cowboys” protect the aphids from predators. Horror-film aficionados should keep an eye out for a species of parasitic wasp that waits until its caterpillar prey is at a vulnerable stage, just before transforming into a hard-shelled larva, to inject its eggs into the caterpillar’s flesh; a few weeks later, the baby wasps hatch and eat their way out of their grisly nursery. For heartwarming drama, look no further than the story of the courageous stink bug mother, who resolutely guards the eggs she has carefully attached to a leaf. Once her dozens of young have hatched, she stands over them like a shield, warding off invading ants and other predators. Then, like a mother duck, she leads her gaggle of hatchlings off to feed.

Finally, sports fans might enjoy the incredibly intense competition among plants for sunlight and growing space. In SECRET GARDEN, time-lapse photography, which compresses days into a few minutes, reveals a no-holds-barred contest for living space that rivals any scramble for a loose basketball. Writhing, twisting, and pushing, each weed races to get ahead of the others — and to leave the carefully-nurtured flower and vegetable opponents in the shadows.

People sometimes “have a very meager understanding of what is going on in their yards,” says Tufts, but “it doesn’t take much to begin to understand what is going on out there and how different plants and animals interact.” The first step to discovering your garden’s secrets, he says, is simply to begin looking.

Online content for Secret Garden was originally posted March 1998.