Date of Award


Degree Name

Doctor of Philosophy


Science Studies

First Advisor

Dr. Robert Hafter

Second Advisor

Dr. Robert Poel

Third Advisor

Dr. Richard Pippen


Both the content and strategic knowledge used in phylogenetic tree construction are described to account for novice performance. A review of the literature is used to place this research with respect to studies in: problem solving studies (both expert, and novice), the history and practice of evolutionary systematics, and the teaching of evolution. The computer-based problem-solving environment is discussed along with model problems used for the research.

Each of the five research problems consists of an encoded matrix containing phylogenetic data organized by taxa and characters. Twelve participants (high school students) volunteered to solve the research problems, on their own time, before and after school. Each participant generated three sets of data: (I) an audio tape dialogue of activities while solving each problem, (2) the completed tree as a computer printout, and (3) any paper and pencil drawings or notes that the participant may have made.

A procedural model of novice performance for phylogenetic tree construction is described with the associated strategies needed to do so. There are four activities that make up the procedural model of novice performance. Those activities are: matrix analysis, building a tree topology, character assignment, and checking. The chief variation between novices and experts is in matrix manipulation and character assignment. Novices did not create any alternative trees nor did they rearrange the data matrix. Once a solution was reached, it appeared to be written in stone. All the novices, however, believed there were alternate trees as evidenced by post research interviews.

Access Setting

Dissertation-Open Access