Friday, October 5, 2012

Oklahoma Teachers Evolution Workshop Begins

Tonight, the eighth annual Teachers Evolution Workshop in Oklahoma begins. It is sponsored by Oklahomans for Excellence in Science Education. We are meeting at the University of Oklahoma Biological Station on the north shore of Lake Texoma near Durant. The meeting has been organized by Dr. Richard Broughton of the University of Oklahoma. The participants are teachers and graduate students from Oklahoma and Texas. The first presenter is Dr. Ola Fincke of the University of Oklahoma. She is most famous for studying the sexual selection of damselflies in distress.

Dr. Fincke is telling us about how to incorporate evolutionary concepts into high school biology teaching in such a way that they are less likely to resist it. She suggests that we get the students to ask questions about why organisms have the adaptations that they do: why do so many insects have camouflage? Why do some flowers stink? Students can figure out answers to these questions. Throughout her session, Dr. Fincke used the question-and-discussion technique, to show that it can work. Sometimes the discussion got a little confused, but not for long; but that is a risk you have to take to allow students to investigate and understand for themselves. The principles of phylogeny can be illustrated by genealogical patterns, which the students already understand. A frog is more closely related to a human than to a fish because frogs and humans share a more recent common ancestor, just as siblings share a more recent common ancestor with one another than with a cousin.

Evolution is both fact and theory: the fact that it happens, and the theory that explains how it happens. It happens by natural selection. Humans have used a type of applied selection to produce many varieties of crops and livestock and pets. Students may be surprised to realize that natural selection, as proposed by Darwin and Wallace, is a common-sense principle: how could it not happen? Natural selection is not chance; therefore, evolution is not caused by "random chance." Natural selection is undirected, but is not random!

The fact of evolution is demonstrated by such things as the vestigial hips in whales, which have no hind legs. It is also demonstrated by the fact that it happens all the time around us: new strains of HIV evolve within the bodies of HIV-positive people. Why do icefish in Antarctic waters, which have no hemoglobin in their blood, still have hemoglobin genes--this can be explained only by evolutionary ancestry. Geneticists can take a gene that stimulates eye production from a mouse, and swap it out in place of the fly eye-production gene, and it still works in the fly--this is an experiment that confirms shared ancestry.

In the discussion that followed, we talked about whether teachers should call evolution what it is. This opened up a big political can of worms, which created an open argument among the instructors to which there was no resolution. But, as Dr. Fincke showed, you can teach evolution through common sense and evidence.

No comments:

Post a Comment