Download The Peppered Moth Name

The Peppered Moth And Natural Selection Name _____________________ Date ___________ Period _____ Introduction: Over many generations natural selection gradually changes a species in response to the demands of its environment. Adaptation is the process by which a species becomes better suited to its environment. The word “adaptation” can also refer to any change in a trait that increases the likelihood of an organism to survive or reproduce. If a mutation occurs within an individual, and it makes that individual better suited for its environment, it will survive and pass on these traits to its offspring until most of the individuals for that population have this trait. For another example of natural selection in action, read the details closely of the peppered moth study. Industrial melanism is the term used to describe the adaptation of an organism in response to a type of industrial population. One example of rapid industrial melanism occurred in the peppered moth, Biston betularia, in the area of Manchester, England, from 1845 to 1890. Before the industrial revolution, the trees in the forest around Manchester were a light grayish color due to presence of lichens on their trunks. Peppered moths, which lived in the area, were colored light with dark spots. Their coloring served as protective camouflage against predators, especially birds. At this time, dark gray peppered moths were rare, and were treasured by British butterfly and moth collectors. As the industrial revolution progressed, the trees became covered in soot, turning the trunks dark. Over a period of 45 years, a change in the peppered moth took place. In this investigation, you will observe the effects of industrial melanism in the peppered moth over the coarse of 10 years. You will then determine the relationship between the environment changes and the color variation of the peppered moth by using research data to graph the effects of environmental adaptation. Materials:
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Class set information sheet
Lab sheet
Graph paper
Colored pencils (2 colors)
Focus question: How did the Industrial Revolution affect the population for the peppered moths in the sample area of England? Vocabulary: Melanin, camouflage, adaptation, natural selection Procedures: 1. Table A contains data from a 10­year study of two varieties of the same species of peppered moths. The numbers represent moths captured in each of 10 consecutive years. The traps were located in the same area each year. Table A Year Number of light moths captured Number of dark moths captured 2 3 4 5 6 7 8 9 10 537 484 392 246 225 193 147 84 56 112 198 210 281 357 412 503 594 638 2. Using data provided in Table A, construct a graph comparing the numbers of each variety of peppered moths. Label the axes with the “years” for the study (X) and the “number of the moths captured” (Y), Use different color variations of the moth. Be sure to label all parts of the graph (including a key for the lines). 3. Use your graph and your textbook if needed, to answer the questions on your lab sheet. Analysis: Answer the following questions based on the introduction using complete sentences. 1. What preys on the peppered moths? 2. If the bark is dark and the moths that rest there are light, what might happen to the moths? Explain. 3. What is a mutation?
4. What could have caused the first few moths to change from a light variety to a dark variety? 5. What event caused the tree trunks of many trees in England to turn from light to dark? 6. Which variety of peppered moth increased over the 10­year period? 7. What is the term that describes this type of evolutionary adaptation? Complete Graph: Use the information found in Table A to complete a correctly labeled and scaled graph paper supplied by your teacher. Conclusion: Answer the following questions using complete sentences using the information found in the lab. 1. Using the data on the graph, draw a conclusion concerning the population of peppered moths in the sampled area of England. 2. Explain the reason (as C. Darwin might) for the increase in the number of dark­ colored moths. 3. What means could be used to return the environment of the peppered moth to its original state? 4. What mechanism of natural selection is taking place in this example? 5. What effect would cleaning up the environment have on the moths?