ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University Student Materials

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Introduction to Our Class Case Studies Name: _____________

• Three of the organisms shown below are wild gray wolves (Canis lupus). • Three other organisms shown below are domestic dogs. Domestic dogs are the

same species as gray wolves (Canis lupus). Gray wolves and domestic dogs can mate with one another and have offspring.

• Three other organisms shown below belong to different species than the wild gray wolf and domestic dogs. They can not mate with dogs or wolves and have offspring.

Make a Prediction Which three pictures are not wolves or domestic dogs? _________________________

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ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University Student Materials

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All nine organisms on the pervious are closely related to one another, and have a common ancestor they descended from in the past. You will study all these organisms over the course of this unit, trying to explain how they came to look and behave differently and how their traits have changed over time. The study of these organisms will be broken into 3 cases to investigate:

• Case 1: Domestic dog breeds (Canis lupus) • Case 2: Different sub-species of gray wolves (Canis lupus) • Case 3: Different species that are closely related to gray wolves (Canis lupus).

You will construct scientific explanations, build models, and argue from evidence to answer these questions about each of the cases:

1. How Did People Develop Breeds of Dogs? 2. Why Do Different Sub-Species of Wolves Have Different Trait Variations? 3. How Are Different Canid Species Related To One Another?

You will be working on these cases with your research team throughout the unit. Save all your case study work from day to day to refer to across the course of the unit. Checking Your Prediction Pictures of species that are different than domestic dog breeds and different than wild wolves (Canis lupus) from the first page are:

o 3 = Coyote Scientific name: Canis latrans o 4 = Kalak Scientific name: Chrysocyon brachyurus

(Also commonly referred to as a Maned wolf, even though it is not the same species as wild gray wolf [Canis lupus]

o 8 = Wildehond Scientific name: Lycaon pictus Also commonly referred to as an African wild dog, even though it is not the same species as domestic dogs [Canis lupus])

Why do you think people gave the Kalak and Wildehond common names that included the word “dog” or “wolf” in them, even though these animals are not the same species as domestic dogs and wild gray wolves [Canis lupus]? _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________

ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University Student Materials

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Name: ______________________ The differences in the traits of these individuals probably helped you tell some of the dogs apart from the wolves and the wolves apart from the other species. You were probably able to tell the dogs apart from the wolves. Why do all these animals have different traits? Share what you know about these organisms and/or brainstorm new ideas that would help explain why they look the way they do: _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________

ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University Student Materials

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What questions do you have about these organisms that you would like to know more about? _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________