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Online Course for Teachers: Teaching Evolution

About this Course 


SESSION 2: How Does Darwin's Theory of Evolution
Illustrate the Process of Science?

Explore Part A: Lamarck, Wallace, and Darwin

Darwin didn't discover evolution; there were many other scientists before him who had argued that species were not immutable. In this part, you will explore the ideas of three scientists: Lamarck, Wallace, and Darwin.


Read Jean Lamarck's "Zoological Philosophy."



What is the role of the environment in Lamarck's explanation?



What scientific approach is suggested by Lamarck's statement: "Nothing of all this can be considered as hypothesis or private opinion; on the contrary, they are truths which, in order to be made clear, only require attention and the observation of facts."



Was Lamarck's explanation scientific? Why or why not?



Can you propose any other explanations for Lamarck's observations about the disuse and use of organs?


Read Alfred Russel Wallace's "On the Tendency of Varieties to Depart Indefinitely from the Original Type."



How would you characterize Wallace's idea, "The life of wild animals is a struggle for existence?" How is Wallace's view scientific?



Wallace claims that "useful variations will tend to increase, unuseful or hurtful variations to diminish." How does this occur? What evidence does he cite?



How does Wallace's explanation differ from Lamarck's?



What do you think of Wallace's critique of Lamarck's hypotheses?


Read excerpts from Charles Darwin's On the Origin of Species.



What led Darwin to formulate his ideas about the origin of species?



On what did he base his explanations?



What did Darwin propose as the origin of species?



Was Darwin's explanation scientific? Why or why not?



How did Darwin attempt to determine how modifications of a species are accomplished?



How did Darwin explain the incomplete nature of his ideas?

After reading all three scientists' views of evolution, answer this question:

What was the relationship of Lamarck's and Wallace's work to Darwin's? On a piece of paper, create a chart to compare and contrast Lamarck, Wallace, and Darwin's theories, and identify the connections between each evolutionary theory.

-- This activity is adapted from Teaching Evolution and the Nature of Science

Taking it back to your classroom.

This activity can also be done with your students using Teaching About Evolution and the Nature of Science.


Facilitator Note 1


Next: Explore Part B: History of Evolutionary Thought

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