Student Conceptions: Origin of Species

Doing a search for ideas on teaching evolution with a constructivist approach, I happened upon this article by W.W. Cobern which makes the point that I alluded to in an earlier post on the importance of tapping into students existing conceptions of reality. I don't like to throw too much jargon around and frankly I don't have much of a memory for pedagogic gobbledygook. Nonetheless, the article reminded me of some of the constructivist principles that underpin my instincts and reminded me of the conceptual change model that's really the basis for my wanting to elicit students' current conceptions, and then present them with data or evidence that they must somehow account for. It's an interesting read, although some of the language and the constructivist bias can be a tad annoying.

And as I stated in the previous post, getting at students' ideas about the origin or origins of species necessarily involves a religious discussion. I jumped right into the discussion today with my 2 regents classes. I asked them to draw a diagram that showed in some way how the earth today came to have over 1.7 million different kinds of living things and to include a timeline. Most students struggled with how to represent their ideas visually. "God did it. How do I draw that?"

I should say that I did model what I meant by a diagram. I had read the word "asteroid" in a student's homework assignment, and elaborated on my own. Here is my model diagram and explanation:

It's a silly idea and a simple diagram, just to illustrate how one might take the idea that all the living things on earth arrived on asteroids from outer space and turn it into a visual representation. I got some interesting stuff, and I would like to post some of the student work, but I will have to get their permission first.

Not surprisingly, many students had a vague notion that god did it, but no understanding, not even a biblical understanding, of how or when that might have happened. A number of students opted not to diagram their religious understanding, which I of course gave them the freedom not to do. They instead diagrammed what they thought the scientific version of events was, and quickly added that they didn't believe it, it's just what scientists think. Needless to say, their diagrams of the scientific view were as sketchy as the religious diagrams.

Tonight's homework was to consider the fossil evidence that some millions of years ago, not one of the species of mammals that live today - giraffes, elephants, whales, humans, etc. - existed. How does your model (diagram) account for this information?