Biology Lab Report - Natural Selection

Ben O’Connor Biology Lab Report- Natural Selection Mrs. Jenkins - SVA Lab Report: Natural Selection Purpose : To explore natural selection using a laboratory simulation. Question : What is the effect of the type of food available on the frequency of different types of bird beaks? Hypothesis : If the type of food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time. Variables Independent Variable: type of food available Dependent Variable: frequency of each type (size and shape) of beak Materials: None, assignment was completed virtually, but if done in classroom you will need: 2 forks, 2 spoons, 2 knives 100 sunflower seeds per trial (500 total if not reusing them) 100 raisins per trial (200 total if not reusing them) 100 grains of rice per trial (500 total if not reusing them) Tablecloth (can be placed on the floor or a large table) 1 cup to collect and store the food Lab Procedure: Lab Procedure Summary : You will simulate three flocks of birds with three different beaks. The birds will compete for three types of food. As they feed, the flocks will change in size over generations. You will repeat this process (with identical flocks) with only two types of food. This will allow you to compare results after the third generation. Step 1: Gather Materials Gather materials noted above. Step 2: Simulate Birds with Three Beak Phenotypes Each flock of birds will have a different beak phenotype. Flock X will have pointed, piercing beaks that are good at piercing. Flock Y will have strong, spoon-like beaks. Flock Z will have thin pinching beaks. If doing this in the classroom, the class should divide into three equally sized “flocks.” Each student should obtain a plastic cup to represent the bird’s stomach and one of the “beaks”: Flock X: pointed, piercing beaks (pairs of forks) Flock Y: strong, spoon like beaks (pair of spoons) Flock Z: thin pinching beaks (pair of knives) Note : if the lab is being completed virtually, omit the steps in ‘ green ’ and follow the instructions presented through the virtual assignment. The steps in ‘ green ’ explain how to simulate the bird beaks and food in a classroom setting.

Ben O’Connor Biology Lab Report- Natural Selection Mrs. Jenkins - SVA Step 3: Simulate an Environment with Equal Amounts of Insects, Seeds, and Fruit You will virtually simulate a field with 300 pieces of food—100 seeds, 100 pieces of fruit, and 100 insects. In the classroom, lay out the food below at random on a large tablecloth. 100 seeds (sunflower seeds), 100 pieces of fruit (raisins), 100 insects (grains of rice) Determine the following: Step 4: Simulate Feeding The birds will use their beaks to pick up as much food as they can. In the classroom: a) Gather around the edge of the tablecloth, mixing the three groups fairly evenly. b) Pick up food pieces only with your tool, using the pair of utensils in one hand, simulating the action of a beak. c) Pick up one piece of food at a time and put it in your cup (“stomach”) before picking another piece of food. d) Keep your body off the tablecloth and pick up food only within your reach. e) Start only when the teacher says “Go” and finish when all food has been “eaten. Step 5: Compile Data and Compute Totals In data Table A, record the number of pieces of each type of food that each flock ate (as a group). Then compute the totals for each flock. In the classroom, count the pieces of each food type in your own cup and add the results with others in your flock to obtain totals. Then ask other flocks to share their data. Record all totals in the data table. Step 6: Use the Data to Model the Sizes of the Flocks in the Second Generation The flock that ate the most will be the most successful at breeding, increasing in size. The flock that ate the least will shrink in size. You will use each flock’s food percentage as its population percentage in the next generation. a) First compute the row of the table titled “Percentage of Food Eaten” using a calculator. Check your computations by making sure that the total percentage is 100%. Which flock will be able to eat the most? The least? Why? Record a prediction on the data sheet. Prediction : Flock X would eat the most simply because their beaks look like they would be best at eating all food types. Flock Z would eat the least because their beaks are thin, so they probably can’t eat much at a time.

Ben O’Connor Biology Lab Report- Natural Selection Mrs. Jenkins - SVA population percentage in the next generation. Compute and enter data into Table C using the calculations in Step 6, items a and b. Once calculated, reassign students to a different flock to account for the changes in the population numbers. Step 13: Simulate Feeding Again Select ‘Start Feeding’. Step 14: Determine the Sizes of the Flocks in the Third Generation The flock that ate the most will be the most successful at breeding, increasing in size. The flock that ate the least will shrink in size. You will use each flock’s food percentage as its population percentage in the next generation. Compute and enter data into Table D using the calculations in Step 6, items a and b. Data Tables: Data - Environment with Equal Amounts of Insects, Seeds, and Fruit Table A: Feeding results of the First Generation Flock X Flock Y Flock Z Insects Eaten 25 33 42 Seeds Eaten 28 45 27 Fruit Eaten 70 21 9 Total Pieces of Food Eaten 123 99 78 Total =300 Percentage of Feed Eaten* 41% 33% 26% Total = 100% Simulated Number of Birds in Flock for 2nd Generation** 12 10 8 (Total birds) Table B: Feeding results of the Second Generation Flock X Flock Y Flock Z Insects Eaten 35 32 33 Seeds Eaten 34 46 20 Fruit Eaten 78 15 7 Total Pieces of Food Eaten 147 93 60 Total =300 Percentage of Feed Eaten* 49% 31% 20% Total = 100% Simulated Number of Birds in Flock for 3rd Generation** 15 9 6 (Total birds) * Divide each flock’s total pieces of food by 300, the total number of pieces of food eaten. Prediction for Data Tables A and B : Flock X would eat the most simply because their beaks look like they would be best at eating all food types. Flock Z would eat the least because their beaks are thin, so they probably can’t eat much at a time. Prediction Correct? Yes

Ben O’Connor Biology Lab Report- Natural Selection Mrs. Jenkins - SVA ** Multiply the food percentage for each flock by the total number of birds (30) (students ) Data - Environment with Equal Amounts of Insects and Seeds but NO Fruit Table C: Feeding results of the First Generation Flock X Flock Y Flock Z Insects Eaten 30 60 60 Seeds Eaten 27 93 30 Total Pieces of Food Eaten 57 153 90 Total =300 Percentage of Feed Eaten* 19% 51% 30% Total = 100% Simulated Number of Birds in Flock for 2nd Generation** 6 15 9 (Total birds) Table D: Feeding results of the Second Generation Flock X Flock Y Flock Z Insects Eaten 15 80 44 Seeds Eaten 17 100 44 Total Pieces of Food Eaten 32 180 88 Total =300 Percentage of Feed Eaten* 11% 60% 29% Total = 100% Simulated Number of Birds in Flock for 3rd Generation** 3 18 9 (Total birds) * Divide each flock’s total pieces of food by 300, the total number of pieces of food eaten. ** Multiply the food percentage for each flock by the total number of birds (30) (students ) Analysis: Based on the data in Table A, Flock X consumed the most pieces of food eaten, with fruit being the most type. Overall Flock X consumed 41% of the food provided. This was also the fact in the 3 rd generation, as demonstrated in Table B, that Flock X again consumed the highest number and percentage of food eaten, with fruit being the most type. On the other end of the spectrum, based on the data in Table A, Flock Z consumed the least pieces of food eaten, but insects were the highest number in the number of pieces of food Flock Z ate. Overall Flock Z consumed only 26% of the food provided. This was also the fact in the 3 rd generation as demonstrated in Table B; that Flock Z again consumed the least number and percentage of food eaten, with insects being the most type of food that Flock Z ate. Flock Y remained in the middle, eating mostly seeds. Flock X increased in size from the 2 nd generation to the 3 rd Prediction for Data Tables C and D : Flock X was more successful at feeing in the previous experiment, so Fock X will have the greatest number in the 2 nd generation. Flock Z was least successful at feeding and will shrink the most. Prediction Correct? No