Biosphere Socratic Questions

Created by Robert Walter and Dorothy Merritts, Franklin & Marshall College (robert.walter@fandm.edu, dorothy.merritts@fandm.edu)

This material is replicated on a number of sites as part of the SERC Pedagogic Service Project

Summary

Questions regarding the biosphere are arranged in sequence for a session of Socratic questioning.

Learning Goals

To understand the definition and uniqueness of life, a primary component of Earth's biosphere. To examine the origin of life on Earth and its evolution through geologic time. To recognize the interactions among the biosphere and other components of the Earth system, including the geosphere, atmosphere, hydrosphere and climate.

Context for Use

This example is suitable for in-class use during a lecture period. No equipment is required unless the instructor wishes to use supplemental images. In that case, the images can be shown either with an overhead or computer projector. Excellent images and other educational resources are available at numerous web sites, and add significant impact to this topic during class discussions. Some examples are given below in References and Resources.

Teaching Materials

Sample questions arranged in sequence for Socratic questioning regarding the Biosphere:

What is life? Describe attributes of life that make it distinctive from other parts of the Earth system, such as minerals, water, or light.

Describe the environment that existed on the early Earth (~3.5 to 4 billion years ago) when life began, then describe what type of organism you might expect to have formed (hypothetically, that is) at that time?

Compare your hypothetical "Common Ancestor" life form to that which scientists think is the first organism to have originated on Earth.

The earliest life forms were simple, membrane encapsulated cells called prokaryotes, such as bacteria and cyanobacteria. What effect might the evolution of prokaryotes have had on the early atmosphere? Why?

The only life forms on Earth from 3.5 to 1.9 billion years ago were prokaryotes. What did the prokaryotes evolve into and why did it take so long for their evolution to occur?

During the Cambrian Epoch, about 540 million years ago, the diveristy of multicellular organisms inceased dramatically. What are some possible causes for such a pronounced increase in biodiversity and why was this particular increase so significant in Earth history?

When did life evolve on land? Way did the evolution of terrestrial organisms occur so long after that of marine organisms?

What is biodiversity and why is it important?

The above and other Socratic questions, with general answers for most, can be downloaded as a PDF file from Biosphere Questions and Answers (Microsoft Word 37kB Jul28 03).

Teaching Notes and Tips

Tips: As in all Socratic questioning, give students time to reflect before answering questions, and make an effort to call on different students throughout the class period. Let students know at the beginning of class whether or not you will call on students randomly, or ask for hands to be raised, or both.

To explore questions on the biosphere fully, allow at least a full class period of 50 to 90 minutes.

Assessment

Many simple details can cause problems when using Socratic questioning. For example, students might feel that they never are given quite enough time to reflect on the answer before called upon. They might not be able to hear some of the other students' answers, especially in a large classroom. They might find it very challenging to take notes during the questioning and response session, and at least will find it more difficult to take notes than during a traditional lecture/chalk class.

The best way to determine what problems are occurring is to give students a questionnaire after each of the first few classes in which the approach is tried. Ask students directly if they think that you are allowing sufficient time for reflection. Ask if they are concerned about hearing other students' responses, and so forth. Add one question that asks students to make note of any problems not referred to in the questionnaire.

Each student should be able to answer any of the questions that was posed during the Socratic questioning session. A good way to assess what the students have learned from a Socratic questioning class is to give a short quiz in which several of the questions from the previous class are listed. This quiz can be given at the beginning of the next class period. If the class is large and grading frequent quizzes is too burdensome, the questions can be designed with multiple-choice answers.