Finch Species Worksheet 2020

The Origin of Species The Beak of the Finch STUDENT WORKSHEET Name:___________________________ ● The 13 species of finches living on the Galápagos Islands evolved from a common ancestor within the last 2 million to 3 million years. ● Finches discriminate between members of their own species and those of a closely related species based on song and appearance. ● A spectrogram is a visual representation of how sound frequencies change over time. Similar songs generate similar spectrograms. QUESTIONS Read the information provided on the first screen of the Click and Learn and by clicking on the “About Daphne Major” and “About Spectrograms” buttons. Then answer the questions below. 1. How do finches recognize members of their own species? As described on the text, it says that one of the male finches starts to sing. Then two male finches in the same species sing the same song, making females finches recognize them as their own species. 2. The Galápagos islands are considered to be “young” islands. Explain what this means. It just means that they were created recently in geological time. They were roughly created about 5 million years ago. 3. The medium ground finch (Geospiza fortis) and the cactus finch (Geospiza scandens) are similar in size and appearance. a. As you can tell from their scientific names, they belong to different species. What taxonomic ranks do they share? The taxonomic rank that they share is that they have different beaks sizes. The cactus finch has a longer beak than the medium ground finch. b. Which physical trait varies the most between these two species? One physical trait that humans could strike the difference between these finches are the beaks. Because of the different sizes they have you could tell them apart. c. The medium ground finch and the cactus finch are adapted to consume different types of foods. Can you think of a situation in which the medium ground finches would have a survival advantage over the cactus finches? A disadvantage? Well one of the disadvantages of the cactus finches are that the medium finch has the ability to break nuts and retrieve seeds due to their shorter beak. 4. From the map, in what ocean are the Galápagos Islands found? Where are they in relation to the United States? The Origin of Species The Beak of the Finch STUDENT WORKSHEET Well the islands are in the Pacific Ocean and part of the country of Ecuador. There is no relation to the U.S since it does not own the islands. 5. Zoom all the way in to Daphne Major. Describe its appearance in two sentences. Daphne Major is a island that is surrounded solely by water. No human has inhabited that island. 6. What is a spectrogram? What variables are on the x- and y-axes? A spectrogram is a visual representation representing on how frequencies change over time. The variable x represents time and that variable y represents frequency. 7. When do the finches on the Galápagos Islands learn their songs? From whom do they learn their song? They learn their songs in a very early stage on their life. For instance, when the small babies finches are on the nest being fed by their father. Click on the “Get Started!” button and answer the questions below as you proceed through the Click and Learn. 8. When the spectrograms were revealed, did you have to change the grouping of any of the finches? ______ Which characteristic did you find it easier to sort by, song or spectrogram? Probably spectrogram for the reason that I needed a visual representation on how they look like when they sang. 9. Did seeing the photos help you sort the finches? Explain. Yes, it helped a lot, especially when seeing the different sized of beaks. 10. At the end of the exercise, which trait allowed you to more easily tell which birds belonged to the same species? (The species name is not a trait!) I will say the beaks, for the reason that you could tell the different sizes.