• Review the Fact and Fiction quiz for background knowledge.
• Assess the whole class during class discussion.
• Observe and analyze student hypotheses for individual assessment.
• Observe and conference with students about specific questions and/or prompts.
• Facilitate small-group discussions to analyze individual knowledge.
• Collect and assess the Where Do Different Dog Breeds Come From? Selective Breeding, and Domestication History of Dogs Reading Guide worksheets.

Part 1

Have students take the Wolves and Dogs: Fact and Fiction quiz (S-8-3-2_Fact and Fiction Quiz and KEY.docx). Go over the answers to the quiz and discuss any answers that students found surprising.

Define the term niche. Ask students to read the article “Wolf to Woof” (S-8-3-2_Wolf to Woof.docx). Explain the two scenarios by which dogs may have become domesticated:

• Natural selection favored dogs that were less aggressive and better at begging humans for food.
• Natural selection favored dogs that were less likely to flee from people as the dogs ate nearby in garbage dumps.

In small groups, have students hypothesize how dogs could have become so different from wolves in terms of their appearance but retained the vast majority of wolves’ genetic makeup. Allow students to discuss in small groups then report out to the class.

Ask students to write down a guess about how many different dog breeds exist in the world today. Explain to students that all dog breeds are members of the species Canis familiaris. Explain that it can be difficult to identify when a type of dog is actually a separate breed. The American Kennel Club officially recognizes 150 breeds, but there are more breeds that exist.

Divide students into small groups and assign each group a breed from one of the lists below. Have students read about the origins of these breeds. Suggested Web sites are the American Kennel Club at www.akc.org/breeds/index.cfm and the Dog Breed Info Center at www.dogbreedinfo.com/abc.htm.

Have students list the countries or regions where these breeds were first developed.

• Older Dog Breeds: Saluki, Afghan Hound, St. Bernard, Alaskan Malamute, Lhasa Apso
• Newer Dog Breeds: Australian Shepherd, Pembroke Welsh Corgi, Miniature Poodle, Mountain Cur

Give each group a copy of the world map (S-8-3-2_World Map.docx) and a colored pencil. Ask each group of students to color-code their map to indicate where their breed originated. Have the groups with older breeds use the same color/pattern, and assign a different color/pattern for groups with newer breeds.

Have a student representative from each group hold up that group’s map and state where the dog breed originated. Ask the class to look for patterns in where dog breeds live in the world.

Discuss the reasons people have bred dogs throughout history (e.g., herding livestock, pulling sleds, carrying loads, hunting, and as pets).

Part 2

Have students read the article “Domestication History of Dogs” available at www.petwebsite.com/dogs/dog_history.htm. Have students answer the questions on the Domestication History of Dogs Reading Guide worksheet (S-8-3-2_Reading Guide and KEY.docx). Discuss the answers to the worksheet with the class or collect it for assessment.

Review natural selection concepts from the previous lesson and compare natural and selective breeding. Emphasize the similarities between them, with the major difference being human intervention in selective breeding.

Have students work in pairs to complete the Where Do Different Dog Breeds Come From? worksheet (S-8-3-2_Dog Breeds Worksheet and KEY.docx) and the Selective Breeding worksheet (S-8-3-2_Selective Breeding Worksheet and KEY.docx). Collect the worksheet for assessment.

For individual assessment have students answer the following questions:

• Should humans keep breeding dogs?
• Compare selective breeding with natural selection. How are they similar and different?

Extension:

• Have students create an imaginary dog breed by selective breeding. Students should include a picture and descriptions of the parent dogs in order to create the imaginary dog breed. Students should also include a picture of the imaginary dog breed and a paragraph explaining some of the dog’s characteristics.
• During Part 2 of the lesson, students who might need an opportunity for additional learning can read the article “Domestication History of Dogs” and write a phrase or sentence to summarize each paragraph in the margin (S-8-3-2_Domestication History of Dogs Article.docx; also available at www.petwebsite.com/dogs/dog_history.htm).
• For students who might be going beyond the standards, provide a different assignment in place of researching a particular dog breed. Have students research the current debate over genetic engineering and cloning, particularly related to dogs. Ask them to prepare written or oral reports that answer the questions:

o   Do you think people will ever be able to clone pet dogs?

o   Do you think people should do this?