Kenyon College -- Department of Biology

BIOL 391: Evolutionary Modeling

Response by David Slochower

The evolutionary modeling class was a fantastic experience. The understanding of dynamical systems, from fractals to schools of fish, is essential for a complete view of biology. And there is no better example of a system governed by a fixed rule that describes the time dependence of the system than evolution. In my experience, evolution is usually taught by presentation of fossil evidence and by appealing to a sense of reason, but without a visual demonstration it is virtually impossible to imagine and predict the effect of even the simplest rules. The computers were paramount to the class, allowing us to observe and indeed control evolution for the first time in a timely manner. For my final project, I attempted to analyze the class of questions which are able to drive evolution. In the program Avida, critters are rewarded for performing simple mathematical tasks (logic functions) and the class analyzed the biological dynamics of these critters throughout the term. If the critters are rewarded for a random variable instead, such as their pixel position on the screen, there is no useful biological information in the population. I was particularly interested in the boundary of what can drive evolution. Because we had read a selection of papers that applied evolutionary modeling to solve complex mathematical and physical problems, such as the traveling salesman problem and simulated annealing, I knew that evolution of the critters occurred in these cases as well. However, there were no studies of the biological dynamics in such situations. I worked with Dave Thomas, a colleague of Dr. Hoppe's at the University of New Mexico, to analyze the biological dynamics of a program designed to solve "good enough" solutions to the Steiner Tree problem.