The Food Web Game. Ohio Academic Content Standards Met:

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1 The Food Web Game Matt Steele Bowling Green State University Chip Harms Kenwood Elementary, Bowling Green City School District Abstract: The Food Web Game uses the format of the popular Project WET activity The Incredible Journey to present content material on food webs. In this lesson students trace the movement of food energy and biomass through a simulated food web, exploring and collecting data on consumer type and producer/consumer/decomposer relationships. Following the lesson the students analyze their collected data to map out a food web and graph observed distributions. Ohio Academic Content Standards Met: Life Sciences Scientific Inquiry Scientific Ways Of Knowing Benchmarks 3 rd -5 th B; 6 th -8 th C 3 rd -5 th B; 6 th -8 th B 3 rd -5 th B; 6 th -8 th A Grade Level Indicators 5 th 1, 2, 3; 6 th 8; 7 th 7 5 th 3; 7 th 7 5 th 2,5; 6 th 2; 7 th 2 Materials: 15 station signs 15 station dice 1 data tables graph paper beads 2 pipe cleaners 2 1 (see attached set up sheet) 2 (optional) Preparation and Setup: The Food Web Game consists of 15 organism stations. Each station is comprised of 1) a small poster or sign displaying the name and picture of the organism, 2) the station die, 3) and, if desired, a container of beads. The station die determines what organism is the next link in the food web. A die is constructed of a cube with names and/or pictures of organisms affixed to each side. The list of organisms represented on each die is given in the station die setup sheet. As an example for the Apples station we find:

2 Apples 1-2 Bacteria 3 3 Worm 2 4 Grasshopper 5 Raccoon 6 Mouse So, two faces of the Apples station die have pictures of Bacteria 3, one face has Worm 2, one face has Grasshopper, one face has Raccoon, and one face has Mouse. Alternatively, a six sided die may be used along with the station die setup list. In this case if a 2 is rolled the students will look up 2 on the station die setup sheet and learn that the Apples have died and are decomposed by Bacteria 3. If the students roll a 5, they find that the Apples have been devoured by a Raccoon. The beads at each station serve as a secondary record keeping system and an extra incentive to hold the students attention. They are not critical to the lesson and may be used at the instructor s discretion. Some possibilities for uses of the beads: 15 bead types with one for each organism station; 6 bead types representing producers, primary consumers, secondary consumers, tertiary consumers, scavengers, and decomposers ; 5 bead types representing producers, herbivores, omnivores, carnivores, and decomposers; 3 bead types representing producers, consumers, decomposers. Prior the beginning of the lesson the instructor sets up the 15 stations around the classroom. The producer and decomposer stations will see the heaviest traffic and should be setup accordingly. The Lesson: The Food Web Game lesson is best implemented over a span of 2-3 class periods. The game itself will likely consume a period and the analysis of the collected data, where the meat of the lesson is held, should be given an additional 1-2 periods. The lesson begins with a discussion of sun as being the origin of food energy for almost all life on earth. If the students have recently studied plants and photosynthesis this is an excellent place to start. One recently successful lesson began with the instructor posing the question: What did you have for breakfast this morning? Cereal emerged as a popular response from the short poll. The instructor than asked the class what cereal was made of. The students noted: that cereal was made of molecules which were made of atoms (a response which makes any science instructor smile, even if not the targeted answer); that cereal contained lots of minerals; that cereals ingredients listed many types of grains, which come from plants. The latter response led to the question: What did the wheat (or other grain) plant have for breakfast this morning? This directed the discussion to the topic of photosynthesis and the idea that the energy we get from our cereal comes originally from the sun. The instructor then turns the class attention to the organism station posters

3 positioned around the classroom. One approach to smooth this transition is for the instructor to note they that the pictures are of a few of their favorite foods; corn, apples, raspberries, frog ( Has anyone ever eaten frog legs for breakfast? ), raccoon, worms. When the exclamations of eeewww gross have subsided, the instructor inquires that if all the station posters are not images of food we eat, then how they are related? The discussion then turns to food chains and food webs. The game is optimized for a maximum of 6-8 groups of students. More groups may be accommodated if necessary, however flow of the game may suffer especially at high traffic stations of the producers and decomposers. Each group of students represents food energy and biomass as it moves through the food web. Groups of students may be assigned randomly to organism station or may take turns starting from the producer stations in order to more accurately depict energy entering the food web. At each station the students 1) record on their data table that they have visited the station, 2) collect a bead (if applicable), and 3) roll the station die to determine what organism consumes them. For the first 15 stations the students visit they record the turn number on the data table in the Visit Order column. In subsequent turn the students simply record a tally mark in the Additional Visits column. If the station at which the students are corresponds to a consumer, the roll the consumer is playing in the transition is recorded in the appropriate Consumer Type category. As an example: Station Visit Order Additional Visits Consumer Type Primary Secondary Tertiary Grasshopper 7 \ Mouse Raccoon \ \ In the above chart we see two visits recorded. On the group s 7 th turn they visited the grasshopper station and on this particular visit the grasshopper was acting as a primary consumer. The second visit occurred on a turn greater than the 15 th, and on that visit the raccoon was acting as a secondary consumer. Once the students have recorded the visit in their data tables they collect a bead and place it on their pipe cleaner. For now it is important that the beads are placed on the pipe cleaner in the order in which they are collected, as they serve as a backup data collection system. For logistical reasons it may be helpful for the students to collect beads for only the first fifteen stations visited. When the students have recorded the data for the station and collected a bead, they roll the station die to determine what organism they are being consumed by and to which station they will go next.

4 The game continues in this fashion for either a set amount of time or a predetermined number of turns. For purposes of future data analysis a target of station visits is optimal. If time allows, the remainder of the period may be used to consolidate class data. Important class data to record includes; total visits to each station, total visits to producer stations, total visits to each of the three consumer types, and total visits to decomposers. The second and (time allowing) class periods third are devoted to analyzing the data collected during the game. Two instructive means of data analysis one which we will focus are mapping out the food web and analyzing distributions in the data. The data collected in this lesson is sufficiently rich that other possibilities certainly exist. (One such avenue might be a Project WET The Incredible Journey style story writing of the student s journey through the food web.) Mapping out a group is an excellent first step in data analysis as many students may find it difficult to understand how the linear station-to-station progression they experienced during The Food Web Game relates to a food web. Each group uses the first 15 stations they visited to construct their group food web. The web is assembled similarly to a concept map with the first station they visited as the central object. An arrow is then drawn connecting the first organism to the second, the second to the third, and so on. If the students passed through the same station multiple times, only one item is needed for the map. Similarly if the same transition occurred twice only one arrow is needed. In some relationships food energy and biomass may travel in both directions, here arrows are needed in both directions. For example a robin eats worm 1, then when the robin dies worm 1 decomposes it. In this case an arrow will point from worm 1 to robin and a second arrow will point from robin to worm 1. When this analysis was preformed with a recent class the instructor provided images of the 15 organisms matching the images used on the station dice and posters for the students to incorporate in their maps. This assisted the students in making connections, as a picture of a colony of bacteria is easier to put in context than a bubble with Bacteria 3 written inside. Once each group has assembled its food web map, it is instructive to compare each group s maps. Even though the same game was used to collect the data, no two groups will have followed exactly the same path between stations making each food web map unique. If time allows it is instructive to synthesize all the group food webs into one large class food web that displays all the experienced organism-organism relationships. Perhaps the most powerful use of the data collected during the course of the game is an analysis to understand distribution relationships in a food web. While it may be interesting to graph distributions from the data collected by individual groups, working with small amounts of data can produce misleading results. (This fact itself may make for a terrific class investigation using the data.) For this reason it s helpful to pool the class data and produce graphs using this. The two most important distributions to plot are the number of producers/primary consumers/secondary consumers/tertiary consumers/ decomposers and the numbers of herbivores/carnivores/omnivores/scavengers. Other

5 interesting comparisons are: primary consumers/herbivores (Why aren t they the same?), secondary consumers + tertiary consumers / carnivores (Why aren t they the same?). Once the data has been plotted the students should be guided toward explaining why the observed relationships occur. (Ex. Why is that we observe smaller numbers as we go from producer to primary consumer to secondary consumer to tertiary consumer?) These questions may be addressed in a class of group discussion format or journal prompt. Possible means of evaluating the content material and scientific processes learned in this lesson include: creating a food web map of certain ecosystem, predicting the relative amounts of food energy and biomass stored by two organisms (ex. Savannah grass vs. lions), journaling relationships between a consumer type and a herbivore/omnivore/carnivore type, tracing the flow of energy and biomass through a set of organisms. References: "The Incredible Journey", Project WET Curriculum and Activity Guide, Bozeman, Mont. : The Watercourse ; Houston, Tex. : Western Regional Environmental Education Council, c1995, pg. 161 "What is the Ecodome?"

6 Food Web Data Table Station Visit Order Additional Visits Consumer Type Primary Secondary Tertiary Grasshopper Mouse Raccoon Robin Frog Wolf Vulture Corn Raspberries Apples Bacteria 1 Bacteria 2 Bacteria 3 Worm 1 Worm 2

7 Corn 1-2 Bacteria Grasshopper 5-6 Mouse The Food Web Game: Dice Setup Mouse 1-3 Bacteria Raccoon 6 Vulture Raspberries 1-2 Bacteria 2 3 Worm 1 4 Grasshopper 5 Raccoon 6 Mouse Apples 1-2 Bacteria 3 3 Worm 2 4 Grasshopper 5 Raccoon 6 Mouse Bacteria Corn 3-4 Raspberries 5-6 Apples Bacteria Corn 3-4 Raspberries 5-6 Apples Bacteria Corn 3-4 Raspberries 5-6 Apples Raccoon 1-2 Bacteria 2 3 Worm 1 4 Worm 2 5 Wolf 6 Vulture Worm 1 1 Corn 2 Raspberries 3 Apples 4 Frog 5-6 Robin Worm 2 1 Corn 2 Raspberries 3 Apples 4-5 Frog 6 Robin Grasshopper 1 Bacteria 1 2 Bacteria Frog 5 Robin 6 Raccoon Robin Frog 1-2 Bacteria 2 3 Bacteria 1 4 Worm 2 5 Worm 1 6 Raccoon 1-4 Bacteria 3 5 Raccoon 6 Vulture

8 Wolf 1-2 Bacteria 2 3 Worm 2 4 Worm Vulture Vulture 1-3 Bacteria 3 4 Worm 1 5 Worm 2 6 Vulture