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Bird Beaks Lab. Who will survive? Objective: I can construct an explanation based on evidence that describes how beak shape (trait) can affect the fitness of a bird. Do Now:. Take out your notebook and a pencil :
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Bird Beaks Lab Who will survive? Objective: I can construct an explanation based on evidence that describes how beak shape (trait) can affect the fitness of a bird.
Do Now: • Take out your notebook and a pencil: • Adaptation: a change or the process of change by which an organism or species becomes better suited to its environment. • Clear off your desk (besides your notebook and pencil) • Follow directions on the following slides to create your lab write up(yes, you are turning this in on THURSDAY 1/24.)
Problem/Question? How did the finches on the Galapagos Islands all end up with different shaped beaks?
Background: Hopefully, you recall that Darwin was amazed by the variation in the characteristics of plants and animals he encountered on his journey. In any habitat, food is limited and the types of foods available may vary. Animals that have variations that enable them to take advantage of available foods will be more likely to survive. We call beneficial inherited variations adaptations. Adaptations are inherited characteristics that increase an organism’s chance of survival. Those with the most helpful adaptations will be the most likely to live long enough to pass on their genes to the next generation. This process ensures that beneficial adaptations will continue in future generations, while disadvantageous characteristics will not. Understanding the concept of adaptive advantage is absolutely required for an understanding of how populations exist in ecosystems as well as the process of evolution.
Hypothesis FINISH THE STATEMENT BELOW or CREATE YOUR OWN. If the finches on each island all have different beak shapes, then they developed that way because… Skip a few lines to add more information in a minute!
Rules: Your goal is to compete with the other birds and to gather as much food as possible in each environment. Food items will be "on the ground" (your table), and you must use only your assigned "beak" to pick up the food. Food must be picked up off the table, and placed into your "stomach" (your free hand), which must be held up against your body. Your stomach must remain above the level of the table at all times. You may not use your beak for any other purpose than picking up food off the table. For example, you cannot steal food from another bird's beak, nor can you stab the other birds or try to knock food out of their beak. If the other players agree that you are cheating, you must "regurgitate" all of your gathered food back onto the ground. When all of the food is gone, count and recordhow many food items each bird captured in that environment, put things back as you found them, and then move on to another environment. • You must wait to move on to the next table until I tell you to rotate
Finish your hypothesis… What do you think will happen in each trial? Which beak will be successful? Use what you know about natural selection and survival of the fittest to create your OWNprediction.
Create the data table below in your notebook. Record the amount of food eaten by each beak for trials 1-6.
Materials • Clothes Pin • Binder Clip • Spoon • Chopsticks • Pencil • Graph paper • Paper Plate • Rubber bands • Marshmallows • Paper clips • Gravel • Pennies • Shells
Procedure • Select your beak type (it will not change). • Wait for “food” and for Ms. B to say “eat.” • “Eat” as much as you can in 30 seconds. • Place each item you “eat” in your hand. • After time, count how much your bird/beak ate. • Record numbers in data table. • Move to the next environment (table).
Let’s Discuss: • What is your independent variable? • What is your dependent variable? What did you notice about the behavior of the “birds” with various beaks? Obviously, most habitats have more than one food type available. What would your strategy be if all food items were available?
ResultsCreate a bar graph showing results for just your own beak and each food type. Y Amount of Food Eaten X Marshmallows Paper Clips Rubber Bands Gravel Pennies Shells Environment/food
ResultsCreate a bar graph with Six columns showing results for each trial/environment of each type of beak. Y Marshmallows Amount of Food Eaten X Chopsticks Spoon Small Binder Clothespin Beak Shape
CER (Claim, evidence,reasoning)* • The ____ beak is the best adaptation for this experiment. (or you may use your own format for the claim) • My evidence is: (use your graphs and data tables to justify your claim). • An adaptation is _____. My evidence supports my claim that the ______ beak is the best adaptation because _________________________________ *This paragraph should include explanation of your claim using evidence and data gathered or observed then justify your claim with reasoning based on your hypothesis. Should be a minimum of 6 sentences.
Conclusions • Which type of beak was best adapted to each type of food? Which beak was least adapted to each type of food? Explain. • Assign each of the beaks(birds) a rank from 1 to 4 within each environment, where 1 represents the most food eaten and 4 represents the least. Discuss the advantages and disadvantages. 3. What if the shells were high–protein beetles that were 4 times more nutritious than any of the other food items? How would your feeding strategy change? 4. How are Darwin’s finches an example of natural selection?
