natural selection

click to print from Adobe Acrobat Reader
PREVIOUS PAGES

MUSE | Natural Selection

NEXT PAGES

Modeling View of Science

Our Research

Teaching Strategies

Learning Outcomes

Assessment

Unit overview and MATERIALS

photograph of paleozoic brachiopodsEvolution, the conceptual cornerstone of biology, provides a lens though which each of the sub-disciplines in the biological sciences can be viewed. As such, evolution is to biology what atomic theory is to the physical sciences; a point made over three decades ago by Theodozius Dobshansky in his oft-quoted assertion that "nothing in biology makes sense except in light of evolution" (1973). More recently, the centralness of evolution to an education in science has been prominently featured in the two most influential U.S. science education reform documents - the National Science Education Standards and the Benchmarks for Scientific Literacy. However, by many accounts, evolutionary biology, when taught at all in the nationís high schools, is taught as a set of assertions, leaving students with few insights into what problems are important to evolutionary biologists or how they conduct inquiries to solve those problems.

In the nine-week evolutionary biology unit shared here we have focused our attention on introducing students to key aspects of the practice of evolutionary biology with an emphasis on Darwinís model of natural selection (and the reasoning processes that are involved in using it to explain data). The unit is consistent with the Project MUSE modeling view of science. However, evolutionary biology, because of its reliance on the reconstruction of past events (from changes to a morphological character within a species to speciation events where a single species becomes two) is not adequately characterized with only a modeling perspective. Thus, in our unit, we have also included opportunities for students to be engaged with activities where the historical reconstruction of events is important.

To accomplish this we have created a classroom that has the look and feel of a community of evolutionary biologists, in which students strive to understand the natural selection model and all that it entails. In this classroom students have numerous and varied opportunities to solve realistic problems and engage in public presentation and debate concerning their problem solving. Much of this is accomplished by having the students interact with data-rich cases. Because they provide many opportunities to think with and about powerful ideas in evolutionary biology, students are exposed to the following concepts and cognitive skills.

Concepts

  • Developing a sophisticated understanding of the natural selection model.

  • Using a model to create Darwinian Explanations for data sets related to important biological phenomena.

Cognitive Skills

  • Creating models to account for phenomena.

  • Recognizing patterns in data.

  • Designing investigations to test models or model-generated hypotheses.

  • Assessing models for fit with data and for consistency with other models.

  • Revising models based on new data or new knowledge of other models.

  • Using models to make predictions about new data or patterns in data.

At this site you will find more complete descriptions of the unit as well as the specific instructional materials that comprise the unit. Accompanying each of these descriptions are valuable supplementary materials including: teacherís notes about the actual implementation of the materials; descriptions of common misconceptions that have been reported in the literature related to the content of the material; examples of student work; examples of assessments used; pictures, video, and audio of the classrooms; and descriptions of the intended learning outcomes for students.

roadblocks to understanding natural selection

Educational research has identified particular difficulties, or roadblocks, that are common for students as they learn natural selection concepts. Here you will find several specifics that we feel can be particulary problematic for students as they learn natural selection.

Click on the icon to the left to learn how to successfully navigate these roadblocks.

 

NEXT PAGES

Modeling View of Science | Our Research | Teaching Strategies | Learning Outcomes | Assessment | Unit Overview and MATERIALS