Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Ronald G. Good


The purpose of this study was to use deep time, that is geologic time as a mechanism to explore middle school students' understanding of the natural history of the earth and the evolution of life on earth. Geologic time is a logical precursor to middle school students' understanding of biological evolution. This exploratory, mixed model study used qualitative and quantitative methods in each stage of the research to explore sixth grade students, understanding of geologic time, their worldviews (e.g., conceptual ecology), and conceptual change. The study included fifty-nine students in the large group study and four case studies. The primary data collection instrument was the Geologic Timeline Survey. Additional data collection instruments and methods (e.g., concept evaluation statement, journal entries, word associations, interviews, and formal tests) were used to triangulate the study findings. These data were used to create narrative modal profiles of the categories of student thinking that emerged from the large group analysis: Middle School (MS) Scientists (correct science), MS Protoscientists (approaching correct science), MS Prescientists (dinosaur understanding), and MS Pseudoscientists (fundamental religious understanding). Case studies were used to provide a thick description of each category. This study discovered a pattern of student thinking about geologic time that moved along a knowledge continuum from pseudoscience (fundamental creationist understanding) to prescience (everyday-science understanding) to science (correct or approaching correct science). The researcher described the deep-seated misconceptions produced by the prescience thinking level, e.g., dinosaur misconceptions, and cautioned the science education community about using dinosaurs as a glamour-science topic. The most limiting conceptual frameworks found in this study were prescience (a dinosaur focus) and pseudoscience (a fundamental religious focus). An understanding of geologic time as Piaget's system of time (e.g., chronological ordering of events, before and after relationships, duration or evolutionary time) was a necessary conceptual framework for students to develop a scientific understanding of deep time. An examination of students, worldviews and the interface of science and religion indicated that students often successfully applied a demarcation between science and religion in their public thinking (e.g., the formal classroom setting), but in their private thinking, the demarcation was often blurred.