Virtual Galápagos
Unit 4 Lesson 3: Common Ancestry
Tortoise Curriculum Lesson Plan
LEARNING GOALS AND OBJECTIVES:
- Goal 1: Goal 1: Students will be able to demonstrate their understanding of what a common ancestor is, and the significance of a common ancestry.
- Goal 2: Students will be able to arrange a tortoise species phylogenetic tree and locate the existence of common ancestors on the model.
STANDARDS
Next Generation Science Standards
- 3-LS3-1: Analyze and interpret data to provide evidence that plants and animals have traits inherited from parents and that variation of these traits exists in a group of similar organisms.
- 3-LS3-2: Use evidence to support the explanation that traits can be influenced by the environment.
KEY TERMS AND CONCEPTS
- Common ancestor: an ancestor that at least 2 species share
- Phylogenetic tree: a diagram that shows how different species are related through evolution; it helps to show what species share common ancestors and how they have changed over time; the representation of the evolutionary history and relationships between groups of organisms
PRIOR KNOWLEDGE AND SKILLS
- Ancestry Lesson 1: DNA and inheritance of traits
- Ancestry Lesson 2: Adaptations, Natural Selection, and Evolution
ADVANCE PREP FOR TEACHER KNOWLEDGE
In order to determine how different species are related to each other, scientists use phylogenetic trees. Each branch on the phylogenetic tree shows a different species. The farther branches are from each other, the more different the species are from one another genetically and the more distantly related they are. Another benefit of phylogenetic trees is that they show common ancestry. The notches in the tree represent the common ancestor. In the case of the Galápagos tortoises in the story, their friend Geo, the South American Chaco tortoise is the closest extant relative of the Giant Galápagos tortoises. Geo and the Galápagos tortoises share a common ancestor found on the phylogenetic tree. In addition, the sea turtle is the farthest branch on the phylogenetic tree, so it is the most distantly related species.
MATERIALS AND SETUP
- Virtual Galápagos Ancestry Unit Interactive Game:
- Virtual Galápagos Fieldbook
- Tortoise Phylogenetic Tree activity:
- Scissors
- Glue
LESSON SEQUENCE
ENGAGE
- Students watch the video that introduces the module, and encourages students to consider whether Becki and Tomás are related to each other.
- Students make an initial claim as to whether or not Becki and Tomás are related on their Scientific Field Notes page at designated pauses during the video.
EXPLORE and ELABORATE
- Students explore an activity to introduce phylogenetic trees:
- Using the Phylogenetic Tree worksheets, students cut out the tortoise species information cards and the two labels.
- Students arrange the tortoise species information cards on the branches of the phylogenetic tree and place the two labels at the notches on the phylogenetic tree.
- This activity may be challenging for students and we suggest encouraging students NOT to immediately glue down the cutouts. Rather, they should try different arrangements on the tree and think through/discuss with one another why they are placing each cutout in that position.
- Students also have the opportunity to reflect on their learning, identifying points of confusion, things they understand, and questions they may have.
- Worksheet title: Tortoise Phylogenetic Tree!
- Watch the video following up on phylogenetic tree activity and moving investigation forward.
EXPLAIN
- Students watch the video that introduces phylogenetic trees.
- Then, students watch the animated whiteboard video on Phylogenetic Tree models.
EVALUATE
- Students will write/give explanations as to why they placed each species card where they did on the phylogenetic tree.
- Students can watch the Ancestry (Tortoise Module 4) summary video.
- Students should revisit their initial claim from the start of this module about whether or not Becki and Tomás are related on their Scientific Field Notes worksheet and revise it given what they have learned in these lessons.
EXTRA
- Students can watch the Adaptations: Land Snail Example with Dr. Parent video for more application of the concepts of adaptation and common ancestry as part of her research.
- Students can also fill out a crossword puzzle that incorporates many of the concepts from this module.
DIFFERENTIATION
- There are two versions of the common ancestry guided notes handout that teachers can choose from for each student. One version asks students to write in responses and the other asks students to circle the right answer.
- For students who are unable to use scissors, students can be grouped into pairs, where one student cuts out the cards and the other student arranges the cutouts on the phylogenetic tree for example.
ASSESSMENT
- Teachers can give students adequate time to return to their “My Scientific Field Notes: Ancestry” handout and follow the CER (claims, evidence, reasoning,and revision) guided thinking to work towards coming up with an answer to the ancestry module mystery question of “Are Becki and Tomás related?”
- Students can further reflect on their own learning by using the “comprehension, confusions, and curiosities” chart provided.
- Teachers can print out additional charts if wanted or use alternative student reflection tools. Then, teachers can collect students’ field books after each lesson in the module and assess their comprehension, curiosities, and confusions thus far.
This unit was designed by Regan Todd and Andrew Lass, and edited by Ava Wojtaszek and Sarah Jekel.
You can download the lesson plan here:
Virtual Galápagos
virtualgalapagos.colgate.edu
