WHAT IN EARTH IS EVOLUTION?

In this presentation, we will demonstrate the use of geological concepts and principles as an effective approach to teaching evolution and in turn the scientific method in the classroom. This approach to teaching makes it easier for students to understand the basic concepts of evolution which is important if we want to understand nature as it really is, for example: that the genetic code is universal for terrestrial life forms, that basic mechanisms of life are very similar in seemingly diverse life forms, that we are part of an interrelated web of energy and life on the planet earth, and that diversity and unity are characteristic of living systems, etc. Evolution deals with the complex mechanisms that make up biological evolutionary change and thus many have argued that nothing in biology makes sense except in the light of evolution. Evolution provides a basic understanding of the fundamental characteristics of life at all levels and thus students cannot adequately understand the relationships of organisms to each other and to their environment without substantial knowledge of evolutionary theory and population dynamics.

The model we have used in teaching evolutionary biology through the geological perspective consists of three integrated components. The first of these deals with the nature of science and what constitutes scientific compared to non-scientific explanations of observations and phenomena. The second component examines the notion of geologic time and the age of Earth, from the combined standpoints of Steno's Laws, the record of ancient life on Earth, and radioactive age determinations on rock materials. The third looks at the implications of the age of Earth and our concepts of geologic time on our understanding of the evolution of life. With the combination of these three components, biological evolution is introduced and explored in the classroom. For example, we can begin to examine questions like; "How could the relatively few and simple organisms of billions of years ago give rise to the many, complex organisms that inhabit Earth today?"