The Tree/Web of Life (Lesson 14: Great transformations in life)

LESSON PLAN: MIDDLE SCHOOL
Great transformations in life, but what was happening on Earth?
[ezcol_1quarter]Main Idea:[/ezcol_1quarter] [ezcol_3quarter_end] The story of life tells us that all living organisms have a common ancestor: the Last Universal Common Ancestor (LUCA). Time and changes to its descendants have produced the incredible variety of creatures we see today. This information needs to be put into context within the lifeline of the planet.[/ezcol_3quarter_end]

[ezcol_1quarter]Objectives:[/ezcol_1quarter] [ezcol_3quarter_end] 1. To verbalize the connections between the major transformations in life and major events on Earth.
2. To extract information from Web sites, books, instructional videos, and other teacher-approved sources.
3. To be able to construct, describe, and evaluate a poster depicting the great transformations during Earth’s lifeline.
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[ezcol_1quarter]Students’ Skills:[/ezcol_1quarter] [ezcol_3quarter_end] Observation, application, analysis, making use of knowledge, synthesis. These skills were drawn from Bloom’s Taxonomy and the constructivist list. NGSS connections: MS-LS1 From Molecules to Organisms: Structures and Processes; MS-LS2 Ecosystems: Interactions, Energy, and Dynamics; and MS-LS4 Biological Evolution: Unity and Diversity.[/ezcol_3quarter_end]

[ezcol_1quarter]Materials[/ezcol_1quarter] [ezcol_3quarter_end] 1. For the lecture and discussion: textbooks, material reference, short PowerPoint or posters depicting the Tree of Life and Earth’s history.
2. For the activity: construction paper, crayons, colored paper. [/ezcol_3quarter_end]

[ezcol_1quarter]Lesson:[/ezcol_1quarter] [ezcol_3quarter_end] 1. Entry card:  Let’s remember the landmarks during the lifeline of our blue-green planet. Can you list two? Allow time for the students to ponder and to write down their answers. Start the discussion by eliciting students’ responses. Discuss the importance of this lesson, and how it relates to past classes. Write the objectives on the board.

2. Show the lifeline of the planet and, with the input of the students, write the main events or “transformations in life” on the board: (a) From unicellular to multicellular organisms, (b) The great oxygenation event, (c) Fish novelties (backbone and legs), (d) Water to land: plants, (e) Water to land: animals (amniotic egg), (f) Rise of the mammals (placenta, brains). Answer students’ questions. Keep all this information visible.

3. Separate the students into six groups, assign each group one event (drawing numbers from a basket), and provide them with construction paper and crayons. Explain the task; each group will construct a poster on the event assigned. The purpose is to describe the environment: What was happening on Earth at that time? Did the event cause a change in the environment and affect the organisms living in it? Make a connection between Earth and the biosphere. The input of the teacher is crucial and scaffolding is necessary. The resources that the students may use are: their portfolios to remember past work, books, readings, and perhaps Web sites suggested by the teacher. Allow time for the students to work on their posters. Circulate and engage with the students, giving support or challenging them. Tell them that the posters will be hung on the classroom wall.

4. Each group of students will visit all the other posters. Their task is to peer review each poster and write a comment, correction, question, suggestion, or addition with different-colored crayon/pen. Ask students to leave their input next to the poster.

5. Have the students regroup, consider the comments, and review their posters. Tell students that they will present their posters at the beginning of the next class, after they have thought about it and written their homework paragraphs.

6. Exit card: “One thing that you have learned today,” and “one concept you still do not understand or want to know more about.” Answer the question: Did we cover your favorite event in life’s history?

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[ezcol_1quarter]Class Closing:[/ezcol_1quarter] [ezcol_3quarter_end]
1. Collect entry/exit cards and posters.

2. Homework: List three things that can be added to your poster to make it better, and write a small paragraph about whether the events on Earth influenced the transformations of organisms or the other way around. Give one example.[/ezcol_3quarter_end]

[ezcol_1quarter]Assesment:[/ezcol_1quarter] [ezcol_3quarter_end] 1. Participation in class and discussions. Presentation of results, and thoroughness and detail in completing their work.
2. Grading: Homework.
3. Use a general rubric to evaluate the students’ overall performance.[/ezcol_3quarter_end]

[ezcol_1quarter]Teacher’s Reflections[/ezcol_1quarter] [ezcol_3quarter_end]1. Things that I did not cover.
2. Did I meet the lesson objectives?
3. Comments, conclusions, and modifications.
4. Pedagogical value of the lesson. Did my students learn the concepts and ideas explored in this class? Did the assessments provide enough evidence of understanding?[/ezcol_3quarter_end]

[ezcol_1quarter]Notes to the Teacher[/ezcol_1quarter] [ezcol_3quarter_end]1. This lesson is important because it allows students to revisit past concepts. When this class was taught, we remembered and talked about the shape of the cladistics map, and why it is in the shape of a tree. The students had been studying the Tree of Life and specific groups of organisms. They spent a lot of time studying prokaryotes, eukaryotes, and the differences and similarities between them. Each group had to do a more in-depth study of the characteristics that identify different families or phyla. The students were aware that all started with a cell and got more complex with time. Also, they understood that the environment is a big factor in what the animals look like. There were several reasons for this class. First, I wanted the students to put all the concepts studied in the last couple of weeks together. Second, the idea of relatedness and common ancestry among animals was emphasized a lot, but I wanted to consolidate this concept once again. Third, so far in this unit, we had talked about new characteristics that an animal adopts as it branches from the Tree of Life and how it differs from other animals, but we had not actually focused on how this transition happened and the connection to the environment.

2. It is important that the teacher provides scaffolding to make sure that the students learn what they need to know.

 

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ACTIVITY: MIDDLE SCHOOL
Great transformations in life, but what was happening on Earth?

cropped-owlet_logo.gifThe story of life tells us that all living organism have a common ancestor: the Last Universal Common Ancestor (LUCA). Time and changes in the descendants have produced the incredible variety of creatures with whom we share Earth. This information needs to be put into context with the lifeline of the planet.

Let us find out what was happening on Earth!

1. Your teacher will place you on a team, and assign your group one event in the history of life by drawing numbers from a basket. You will also be provided with construction paper and crayons.

2. Your task is to construct a poster on the event assigned.

3. Your guiding questions are:

  • What was happening on Earth at that time?
  • Did the event cause a change on the environment, and affect the organisms living on it?  Expand your answer and give an example.
  • Make a connection between Earth and the biosphere.

 

4. The resources you may use are: your portfolio to remember past work, books, readings, and Web sites suggested by your teacher.

5. Start working. When your teacher indicates, all posters will be hung on the classroom wall.

6. Each group of students will visit all the other posters; your task is to peer review each poster and write comments, corrections, questions, suggestions, or additions with different-colored crayon/pen. Leave your input next to the poster.

7. Regroup with your original partners, consider the comments, and review your posters. You will present your finished posters at the beginning of the next class.