Tuesday, May 26, 2015 HOMEWORK: None OBJECTIVE : I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence DO NOW: Discuss an important part of one of the mountain sheep models you looked at.

Introduction We are going to continue to work on developing a model that can help us explain all the interesting phenomena we saw on the introductory slides several days ago. We’ll also keep learning to think about evidence and how evidence can help us rule out some models, choose other models, and revise models to make them better. 2 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Introduction Today we’ll develop models that can explain why the color of the peppered moths changed over the past 60 years. As you develop a new model of how the moths changed, use what you learned from the models of how the mountain sheep changed. 3 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Peppered Moths 1. Lets read the introduction on Page 1 together as a class. In the 1950s, the woods and forests in some parts of the US and England were dirty with black soot from factories. The soot covered everything from buildings to trees. The trees in these forests are naturally lighter in color, but the soot from the smoke stacks make them look very dark. Gradually, from 1959 until today, air pollution laws have led to less air pollution. Because there is less soot produced by the factories, the trees have less soot on them. The old soot gets washed away over time by wind and rain, and the trees’ lighter natural color can again be seen. There are moths called peppered moths that live on these trees. They are called peppered moths because they have black speckles on their wings. In 1959 and the early 1960s, most of the moths that lived in these woods were darker in color. But now, few of the moths are darker in color. Most of the moths are lighter in color. 4 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Peppered Moths TREES WITH SOOT TREES WITH NO SOOT 5 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Problem: Why did these changes happen to the peppered moths? Individually, read Evidence 1-3 to help you develop a model of how these changes occurred. Evidence #1: In 1959 and the early 1960s, about 90% of the peppered moths had darker colored wings. Now about 10% of the peppered moths have darker colored wings, and the rest have lighter colored wings. Evidence #2: Scientists found dark wings on peppered moths are not stains or dirt on the wings from soot or pollution. The color is in the wings. Darker wings are really darker in color, and lighter wings are really lighter in color. Evidence #3: There is variation in wing color of the peppered moth population. Some moths are very light all over, some are very dark all over, and some are different shades of darker and lighter colors in between, as these pictures show: 6 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Initial Model Using this evidence, explain why you think peppered moths’ wings are lighter today but were darker in Individually, develop an initial model. 10 minutes * Remember to think about what you learned from the models of the mountain sheep. Try to come up with a different model from when you first did this. 7 Who wants to share their initial models with the rest of the class? Why do you think your model is a good model? I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

New Evidence 4.In groups, complete Evidence 4-6 on the evidence sheet. After you are done with each piece of evidence, discuss the questions for that evidence. When you all agree on the best answer, circle it. * Be ready to share your answers with the rest of the class. After you complete all the evidence, we’ll quickly go over your answers to the questions. 8 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Evidence 4 Questions 9 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Evidence 5 Questions 10 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Evidence 6 Questions 11 I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence

Closure Summarize the findings of Evidence 4-6. I will create models that show the change in a species over time, multiple generations, offspring and final version of a species using information learned about variation and selection pressures from evidence