To engage students in lesson I have students visit Mutt Maker, an Animal Planet computer simulation. The objective of this activity is for students to create their own dog breed using a combination of traits (face, trunk, legs, tail) from various dog breeds. The site gives students a brief description of all the dog breeds which students can choose from to create their new dog breed. Once students have created their dog breed they are required to write down its unique name.
Teacher Note: This is a good starting point, even though it is a bit extreme and not entirely scientific, about how human can influence the inheritance of desired traits in dogs and other organisms. (MS-LS4-5. Gather and synthesize information about the technologies that have changed the way humans influence the inheritance of desired traits in organisms.). Since dog breeding is the focus of this lesson this sets a foundation for the remainder of the lesson's activities. It's also important to time this activity (5 minutes) since students will want to keep on running this activity to create numerous dog breeds.
To follow up I show students From Wild Wolves to Man's Best Friend by the California Academy of Sciences.
This short video discusses how through the years humans have used artificial selection as a means to obtain dogs with desirable traits, for example for the purpose of hunting. (CCC - Cause and Effect -Phenomena may have more than one cause, and some cause and effect relationships in systems can only be described using probability.)
As students watch video they are required to write down at least 3 dog breeds including a brief description of their desired traits.
In this section of lesson students explore Artificial Selection in Dogs by completing Artificially Selecting Dogs, an inquiry activity from the University of California Museum of Paleontology (author Jennifer Johnson Collins).
This activity emphasizes variation, inheritance, selection, and time (number of generations) to help students develop a clear understanding of artificial selection and, ultimately, natural selection. (SP2 - Developing and Using Models)
Overview: Students learn how artificial selection can be used to develop new dog breeds with characteristics that make the dogs capable of performing a desirable task. Students begin by examining canine features and their functions. They are then given a scenario that describes the type of task they need a new breed of dog to perform. They then select two existing breeds they feel will most likely produce a successful new breed and determine the resulting offspring's characteristics.
In this section of lesson I show students Evolution 1: Natural Selection vs. Artificial Selection. This video compares and contrasts natural and artificial selection.
As students watch video I have students complete a Venn Diagram as a learning tool to compare and contrast natural and artificial selection. Don't underestimate the power of the Venn - it is a rigorous tool for 8th graders and helps all students to access complex ideas using a simple approach. I explain more about how to make the Venn a rigorous instructional tool in my reflection.
In this section of lesson students will gather and synthesize evidence to construct an explanation of how humans have influenced the inheritance of traits in dogs. Students are required to gather evidence from lesson (videos, modeling activity) to construct explanation. (SP6 - Construct Explanations/WHST.6-8.2 -Write informative/explanatory texts to examine a topic and convey ideas, concepts, and information through the selection, organization, and analysis of relevant content.