Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Student Materials ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University Case Study 2: Gray Wolves Sub-Species Canis lupus has 39 subspecies currently described, including two subspecies of domestic dog, Canis lupus dingo and Canis lupus familiaris, and many subspecies of wild wolf throughout the Northern hemisphere Domestic dogs show a great deal of trait variation between different breeds. Likewise, wolves show a great deal of trait variation between sub-species, though they can interbreed. The Zoological Gardens of London for example once successfully managed to mate a male European wolf to an Indian female wolf. Wild gray wolves (Canis lupus) species historically ranged over most of the Northwern Hemisphere. There historical range is shown in the map below. Green represents their present range, and red represents where they have been extirpated from (no longer exist in that region). Image credit: http://commons.wikimedia.org/wiki/File:Gray_Wolf_Range.png This reduced range is believed to be largely due to human impacts such as hunting, urbanization, ecosystem fragmentation, and intentional eradication of native wolf populations in the past. Other factors that may have led to the reduced range of wolves inlcude polluation, climate change, and extripation of native prey species. 1 Case Study #2 – Activity Sheet Student Materials ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University Populations of wolves are not all identical. Scientists have classified different populatons of wolves by the physical traits, behavioral traits, their DNA, and where they are found in the wild. They classify these populations as sub-species1. A subspecies is kind of similar to a “breed” for domestic dog. But unlike domestic dogs, these sub-species were not selectively bred by humans to have different traits. The following map shows the historic range of some of these sub-species. Image credit: http://upload.wikimedia.org/wikipedia/commons/c/cd/Original_distribution_of_wolf_subspecies.GIF 1 The most recent comprehensive review (in October 2012) of the genetics studies concluded that the red wolf, eastern wolf, and gray wolf should be re-classified as three distinct species, instead of as sub-species of Canis lupus.. This reclassification helps support conservation efforts for this animals. As, individuals of all these populations can interbreed, we will consider them sub-species of gray wolf for the purposes of this activity. 2 Case Study #2 – Activity Sheet Student Materials ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University Though these sub-species were not selectively bred by humans to have different traits, scientists use differences in traits as one way to tell these these groups of wolves apart. Predict • • • • Will there be a relationship between the typical size of a wolf sub-species and the environments in which they live? Will there be a relationship between the fur coloration found in a wolf sub-species and the environments in which they live? Will there be a relationship between the fur length in wolf sub-species and the environments in which they live? Will there be a relationship between the preferred pack size in a wolf sub-species and the environments in which they live? ______ ______ ______ ______ Explain your predictions:_________________________________________________________________________________________ ______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________ Procedure 1. Your teacher will assign you to a research team. Which trait are you researching?__________________________ 2. Each member should use analyze the attached data packet. Study the data for your assigned trait and the related enviornments for each sub-species of wolf. You may highlight and annotate the data packet. Each member should help summarize the findings in this table: Question to Investigate Is there a relationship between the trait you were assigned and the environments in which wolves with certain variations of this trait live? Discoveries your group made 3 Case Study #2 – Activity Sheet Student Materials ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University 3. The group should create/add an additional new key for the map below to represent showdifferent variations of their trait and then use this key to annotte the map, showing where these variations are found. This is a map model the group will present to class to support their claims. • • • • Skeletal structure (based on length & height: Your group map should show where (a) smaller vs. (b) larger wolf sub-species are found. Fur color: Your group map should show where (a) whitish, (b) tan/yellowish, and c) darker furred sub-species of wolves are found. Fur length: Your group map should show where (a) shorter vs. (b) longer haired wolf sub-species are found. Preferred pack size: Your group map should show where (a) smallest vs. (b) largest pack sizes are found. Image credit: http://upload.wikimedia.org/wikipedia/commons/c/cd/Original_distribution_of_wolf_subspecies.GIF 4 Case Study #2 – Activity Sheet Student Materials ModelSim Evolution 2014v3.0- Center for Connected Learning at Northwestern University 4. Before presenting, the group should make a claim based on their analysis of the data. For this trait, do the trait variations between sub-species appear to be result of genetic drift or the result of natural selection? The group fill in the first row below. 5. As each group presents, make sure to record the claim of the group, whether their map/model supports their claim, and the reasons the additional reasoning the group provided to support their claim. Trait this group studied Claim: Are the patterns in trait variations due to natural selection or due to genetic drift? Did their map model support this claim? What additional reasoning related to mechanisms of natural selection or genetic drift did the group provide to support their claim? 5 Case Study #2 – Activity Sheet