Sunday, October 7, 2012

Oklahoma Teachers Evolution Workshop, Part Seven

As the Teachers' Evolution Workshop sponsored by Oklahomans for Excellence in Science Education drew to a close on October 9, we had presentations and discussions by high school teachers about how to teach evolution, usually in interesting laboratory settings.

Andrea Blair, high school teacher in Broken Arrow, Oklahoma, and a graduate student at the University of Tulsa (where she spends time studying the anatomical structure of amphibians), told the participants about some of the lab activities she has devised or adapted. Some were versions of the natural selection simulations that have been used in many classes for decades; for example, to simulate natural selection of light vs. dark moths against light vs. dark bark, based on the twentieth-century studies by H. B. D. Kettlewell. But the greatest amount of discussion came in response to Andrea's investigation of radiometric dating. Students begin with a box of coins, all heads-up, which represent radioactive atoms. Then the students shake the box just once, count and remove the tails-up, which represent atoms that decayed. The students repeat this over and over, and generate a graph of radiometric decay. But they do so by stimulating a random process (actually a quantum process). I, for one, have never heard about this activity from anyone else.

Andrea also described how to use different colors of beans to represent alleles in a population. Students randomly draw pairs of beans that represent diploid individuals in a population. Then, natural selection can be simulated on the simulated diploids. The advantage of this activity is that students can see the effect of natural selection not on phenotypes but on allele frequencies in a population. This activity can be modified to simulate genetic drift and founder effect.

One thing that Andrea emphasized is that these activities are cheap and easy. You don't need a budget for prepared teaching materials or for computer simulation software. Best of all, students are learning about the processes of evolution, without feeling like "evolution" is being pressed upon them.

And with this, the workshop ended. The participants were, we hope, inspired and equipped to teach evolution in creative ways and to deal constructively with inevitable conflicts. The setting, the University of Oklahoma Biological Station on the shore of Lake Texoma, was restful and beautiful.

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