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MUSE | Natural Selection | Unit Overview and Materials | Section 2: Comparing Explanatory Models


Lesson 2A

Lesson 2B

Lesson 2C

Lesson 2D

Lesson 2E


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Section Two: Comparing Explanatory Models

There are five materials included in this section. The primary goal of this portion of the unit is to introduce students to evolutionary reasoning and specifically to the explanatory power of the Darwinian model of natural selection. This is accomplished by first introducing students to the role of models in science more generally, followed by opportunities for students to read and come to an understanding of three models that account, in their own ways, for species diversity. The three models are:

  • William Paley's model of intelligent design
  • Jean Baptiste de Lamarck's model of use inheritance
  • Charles Darwin's model of natural selection

Once the three models have been elaborated, students will have an opportunity to compare them using the framework developed during the Cartoon Activity (material 1B). This comparison is followed by a discussion about why Darwin's model is the currently accepted model in evolutionary biology.

2A: Introduction to the nature of explanatory models (1/2 of a class period)
2B: Understanding Paley's model (3 class periods)
2C: Understanding Lamarck's model (2 class periods)
2D: Introduction to Darwin's model (3 class periods)
2E: Comparison of the models (2 class periods)