Instincts. Time: 1 Hour 40 Minutes

Transcription

1 Concepts: The balance of predator/prey relationships is delicate and interdependent. A population of particular species fluctuates because of a number of limiting factors. Objectives: The students will be able to define the terms herbivore, omnivore, and carnivore. The students will be able to define the terms producer, consumer, and decomposer. The students will identify how energy flows through an ecosystem from the sun to plants to animals and then into the soil. The students will name at least two strategies that animals use to survive. Equipment: Food and water stations Food and water slips Charts explaining food chain Life tags (3 different colors) Armbands (3 different colors) **Note: The above items can all be found with the Instincts bag in Miami Cabin. Please refill after use** Note to Teacher: Instincts for Survival is a simulation game in which participants portray animals in an ecosystem. The object of the game is for the participant to obtain enough food and water to survive by the end of the playing period without being eaten by other animals. Vocabulary Camouflage- concealment by disguise or protective coloring. Carnivore a flesh-eating animal. Consumer- a heterotrophic organism that ingests other organisms or organic matter in a food chain. Decomposer- an organism, often a bacterium or fungus, that feeds on and breaks down dead plant or animal matter, thus making organic nutrients available to the ecosystem. Food Chain- a succession of organisms in an ecological community that constitutes a continuation of food energy from one organism to another as each consumes a lower member and in turn is preyed upon by a higher member. Herbivore- an animal that feeds solely on plants. Time: 1 Hour 40 Minutes Activities in Lesson: Preparation (10 min) Instincts for Survival (90 min) Instinct- an inborn pattern of behavior that is characteristic of a species and is often a response to specific environmental stimuli. Omnivore- an animal that feeds on both animal and vegetable substances. Producer- a photosynthetic green plant or chemosynthetic bacterium, constituting the first trophic level in a food chain; an autotrophic organism. 87

2 Preparation (10 min) Materials: charts explaining food chain. 1. Poster Board: Two charts explaining the food chain and energy flow should be used at the beginning of the module. These will help to demonstrate how energy passes from one living thing to another. Participants will also begin to understand that energy from the sun and nutrients in the soil are recycled and pass through all levels of the food chain. 2. Make sure boundary markers are intact and visible and investigate terrain for large holes, water sources or any other possible hazards. **At the beginning of the season, take the food and water blocks to the playing area and attach to trees or shrubs with string or twine. Try to hide the blocks so that they are difficult, but not impossible, to find. The food and water stations must be collected at the end of the season.** 3. Begin by asking the students: Is energy exchanged amongst plants and animals? How does energy flow through an ecosystem? 4. Explain how the energy cycle works. Using the posters, point out how much of the original energy from the sun is transferred during each exchange. Explain that animals at the top of the food chain need more energy to sustain themselves. Instincts for Survival (90 min) Materials: life tags, armbands, food & water stations and cards. 1. Begin by asking the students: What is an instinct? How do animals use instincts? What is a way an animal uses an instinct to survive? 2. You will need life tags for each participant. Color-coded tags attached to shower rings work well. You will need six tags per herbivore, four per omnivore, and two per carnivore. Herbivores - white Omnivores - blue Carnivores - red 3. Armbands will represent and match the level of the food chain each participant is. Bands should be worn on arms, not around heads. Herbivores - white (Sample species: grasshopper, deer, mouse, sparrow, rabbit, woodchuck, squirrel, chipmunk, vole, beaver, cricket, box turtle, chickadee) Omnivores - blue (Sample species: raccoon, skunk, weasel, crow, fox, opossum, shrew) Carnivores - red (Sample species: wolves, eagles, mountain lions) 4. Food and water stations are wooden blocks attached with string to a tree, shrub, or the ground. Each card is marked food or water. Each block also has an attached orienteering punch for identification. 5. Food and water slips are pieces of paper with two columns - one for punches from food cards and the other column for punches from water cards. 6. The area of play can be any area of three acres or more that has clearly defined boundaries. Ideally, the area should contain several communities - an edge, a field, and woods; however, this may not be possible so any large area with some good places for camouflage and some running space will work. Currently the area of play is the flagged area behind Oak Shelter 7. The more participants the better; two to three trail groups works well. 8. Explain the rules of the game near the location of the field to be used. Reinforce energy flow in terms of producers, consumers, and decomposers. 9. Explain to the students that they will all be consumers called herbivores, omnivores, and carnivores. Next, define or have the students define the terms herbivore, omnivore, and carnivore. 10. Herbivores - In order to have survived at the end of the game, an herbivore must find four Food Stations and two Water Stations. To prove that he or she has found the Food or Water Station, the player must punch the appropri- 88

3 ate section on the Food/Water Slip. A player may only visit each Food or Water Station once. The herbivore must also avoid being eaten by omnivores and carnivores to survive the game. An herbivore must have at least one of his or her original white Life Tags. If the herbivore has given up all of the original Life Tags to omnivores and carnivores, then the herbivore has died and must see the instructor to be resurrected or to obtain a new role in the game. 11. Omnivores - To finish the game alive, omnivores must find two Water Stations and obtain six foods. An omnivore may eat at a Food Station or may kill and eat an herbivore by tagging the herbivore player. When an herbivore has been tagged, he or she must give the tagger one of his or her original white Life Tags. The herbivore must carefully remove the Life Tag from the shower ring without ripping it, and the omnivore must place the Life Tag carefully on his or her own shower ring. The omnivore may be eaten by a carnivore, so the omnivore must avoid being caught. In order to survive an omnivore must not only obtain the proper amount of food and water, but must also end the game with at least one of his or her original blue Life Tags. 12. Carnivores - Carnivores must find two Water Stations and gain eight Life Tags as food from herbivores or omnivores. Carnivores obtain Life Tags in the same manner as the omnivores. As with the omnivores, the carnivore must end the game with one of his or her original red Life Tags. 13. Explain any game options that will be used during the game. The game options are described below. The instructor may allow dead players who have lost all their original Life Tags or adults accompanying the trail group to play these roles in the game: Humans: Poachers - Poachers kill by shooting at an animal using a soft football and asking for its Life Tag. Humans: Healers - Humans can play a negative or positive role in an animal's life. If this option is used, any dead animal having lost all its Life Tags may see the healer to obtain more. Disease or Disaster - If tagged by this player, an animal must give up one Life Tag. You may choose to have that animal pass the disease to anyone who eats him or her. Other Options - Additional game options may include poisoning an easily visible Food Station or Water Station to simulate what can happen when pesticides or other poisons are introduced into the environment. You can also play a second round with the playing area cut in half to simulate loss of habitat. 14. Explain the boundary areas. Hand out an armband, a set of Life Tags, and a Food and Water Slip to each student. If the student is an herbivore, the student should have a set of herbivore Life Tags.The same goes for omnivores and carnivores. 15. Remind the students that they are to tag others gently and to carefully remove their Life Tags from the shower rings. 16. Explain that predators may not tag the same prey twice consecutively. A second predator happening upon a kill in progress must give the prey a chance to escape before attempting to catch him or her. Carnivores may eat both omnivores and herbivores. Omnivores may only eat herbivores. Herbivores are limited to punching their Food/Water Slips. 17. Give the herbivores a 3-minute head start. Next, give the omnivores a 1-minute head start. Finally, send out the carnivores. 18. Play can last from 30 minutes to an hour. When the game is finished, discuss the game by asking the following questions: Who survived the game by getting all the needed food and water and keeping at least one original Life Tag? What strategies did prey use to escape predators? Did anyone work together to catch prey or escape predators? What group strategies were used? How did you feel being your animal? What happened as different predators entered the game? What would happen if there were more carnivores than herbivores? Is this a true representation of what happens in nature? Name some similarities and differences between nature and this game? 19. Collect all playing materials. 89

4 Evaluation: Students can define the terms herbivore, omnivore, and carnivore. Students can identify how energy flows through an ecosystem from the sun to plants to animals and back into the soil. Students can name at least two strategies that animals use to survive. Notes: Keep in Mind: Observe any hazards that may be in the activity area before playing the game. Large patches of poison ivy, water, etc. need to be pointed out to the other instructors and all of the students to avoid injury. Back in the Classroom: How should the deer population be controlled? Many say hunters should be sent in to kill the excess deer, others say the deer should be relocated to another area, others say predators should be reintroduced to manage the herd, and others say let nature run its course and let the deer die. Invite a wildlife biologist from the fish and wildlife service into your class to speak about deer population issues. Visit a state park or forest to observe the effect of deer overpopulation. Have a debate in your class that contests different methods of solving the deer population issue. 90

5 Background Deer Population State parks and forests around Indiana have been experiencing an increase in the deer herds that inhabit them. The rise in numbers has been happening over time and is due to a number of human related factors. Development is perhaps one of the largest contributing factors. Carrying capacity and habitat space is not inversely proportional. The forests are being asked to sustain more and more deer and there are not the resources available to keep an excessive number of deer alive. The rise in the number of deer is taking its toll on plant growth since the deer will often eat anything green that they can reach. Another human related factor affecting the deer is the absence of natural predators. Humans have removed mountain lions and wolves, which once hunted deer in the area. Ecosystems Ecosystems are maintained only through a continuous cycling of nutrients and flow of energy. All of the activity on earth is ultimately powered by the energy of sunlight. Each time this energy is converted to motion whether of molecules or muscles a certain amount is converted to heat, which then dissipates into the environment, escaping from the food web. Energy flows through the food web in the following way: The sun transmits energy, about 1/50 millionth of which reaches the earth. This energy is then refracted off the cloud layer and about 1% of it reaches the primary producers or green plants. Plants can capture about 3% of the 1% and convert that to useable energy thus the entire food web is powered by about.03% of the energy that the sun puts forth. Energy flows through communities from autotrophs, green plants, to herbivores, omnivores, and carnivores. Each stage of energy transfer is called a trophic, or feeding level. Living things are often classified based on their position in these trophic levels. The first level, producers, consists of all autotrophic organisms, things which can make their own food. The next level, primary consumers, consists of animals that feed on plants exclusively. These are also known as herbivores. This is followed by the secondary consumer, or carnivore, which feeds on primary consumers. Finally, the tertiary consumer feeds on upper level carnivores. Animals may also fall into the category of omnivore these animals act as primary consumers and as secondary consumers. They eat both meat and plants. In any food web there are also detritovores, or decomposers. These animals feed on decomposing life, both animal and plant. They are an important part of nutrient recycling as they turn decaying life into nutrient rich soil on which new plant life can grow. The transfer of energy from one trophic level to the next is not an efficient process. This is best described by the 10% law which states that at each trophic transfers only 10% of the useable energy, while 90% is lost to heat. A given ecosystem can therefore support more animals feeding at a primary consumer level than at a secondary or tertiary level. This is also true for humans. More humans can be fed on a pound of wheat than on a pound of meat. Predator & Prey Predator/Prey relationships exist out of feeding necessity. As animals attempt to survive they must eat and avoid being eaten. Animals which feed on plants expend more energy avoiding predators than capturing food while animals on higher trophic levels spend most of their time and energy finding and capturing prey. All animals have developed defense mechanisms to allow for their own survival. Many animals use camouflage to blend into their environment thus remaining virtually undetected. This can be done by remaining very still and hiding, using coloration patterns to match the environment (ex. snowshoe hare), or mimicking other plants or animals (ex. the walking stick). This approach is also used by predators to ambush or surprise prey. 91

6 Standards Grade Answer questions completely and appropriately Follow three- and four-step oral directions Explain that features used for grouping depend on the purpose of the grouping Describe that almost all kinds of animals food can be traced back to plants Explain how a model of something is different from the real thing but can be used to learn something about the real thing. Grade Ask thoughtful questions and respond orally to relevant questions with appropriate elaboration Summarize major ideas and supporting evidence presented in spoken presentations Observe and describe that things give off heat, such as people, animals, and the sun Observe and describe that organisms interact with one another in various ways, such as providing food, pollination, and seed dispersal Observe and describe that some source of energy is needed for all organisms to stay alive and grow Explain how in all environments, organisms are growing, dying, and decaying, and new organisms are being produced by the old ones Explain how changes in an organism s habitat are sometimes beneficial and sometimes harmful Explain that living things, such as plants and animals, differ in their characteristics, and that sometimes these differences can give members of these groups (plants and animals) an advantage in surviving and reproducing. Grade Restate and carry out multiple-step oral instructions and directions Explain that one of the most general distinctions among organisms is between green plants, which use sunlight to make their own food, and animals, which consume energy-rich foods Explain that in all environments, such as freshwater, marine, forest, desert, grassland, mountain, and others, organisms with similar needs may compete with one another for resources, including food, space, water, air, and shelter. In any environment, the growth and survival of organisms depend on the physical conditions Recognize and explain that two types of organisms may interact in a competitive or cooperative relationship, such as producer/ consumer, predator/prey, or parasite/host Describe how life on Earth depends on energy from the sun. Grade Ask questions that seek information not already discussed Make inferences or draw conclusions based on an oral report Explain how the solution to one problem, such as the use of pesticides in agriculture or the use of dumps for waste disposal, may create other problems Explain how the solution to one problem, such as the use of pesticides in agriculture or the use of dumps for waste disposal, may create other problems Explain that in any particular environment, some kinds of plants and animals survive well, some do not survive as well, and some cannot survive at all. 92