Durham E-Theses Factors Underlying Students' Conceptions of Deep Time: An Exploratory Study CHEEK, KIM How to cite: CHEEK, KIM (2010) Factors Underlying Students' Conceptions of Deep Time: An Exploratory Study, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/277/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk FACTORS UNDERLYING STUDENTS’ CONCEPTIONS OF DEEP TIME: AN EXPLORATORY STUDY By Kim A. Cheek ABSTRACT Geologic or “deep time” is important for understanding many geologic processes. There are two aspects to deep time. First, events in Earth’s history can be placed in temporal order on an immense time scale (succession). Second, rates of geologic processes vary significantly. Thus, some events and processes require time periods (durations) that are outside a human lifetime by many orders of magnitude. Previous research has demonstrated that learners of all ages and many teachers have poor conceptions of succession and duration in deep time. The question is why. This exploratory, qualitative study investigates the viability of a model (a deep time stool) to capture the underlying factors necessary for a concept of deep time. The model posits that a concept of deep time rests upon: an understanding of succession and duration in conventional time; a robust understanding of large numbers and the proportional relationships among numbers of various magnitudes; and a learner’s geoscience content knowledge. While all three factors may not exist to the same degree in any one individual, all must be present to support a conception of deep time. Thirty-five students in the United States participated in individual task-based interviews: 12 eighth and 11 eleventh graders from a public charter school in the U.S. and 12 university students from two institutions enrolled in an introductory geoscience course. Tasks and questions probed students’ understandings of the three factors within and outside a deep time context, and the study is unique for that reason. Results indicate all three factors play an important role in how students understand deep time. While succession in conventional time proved non-problematic, duration was more difficult for participants. Some students were confused about the relationships among numbers in the thousands and millions, and others appeared to have little understanding of time periods up to 100 years. Participants had just as much difficulty dealing with the duration for events in conventional time as they did for those in deep time if the events were unfamiliar to them. Time and number share a similar spatial mapping strategy while knowledge of large numbers and geoscience content knowledge appear to provide reference points that can be used to judge the temporal order or duration of geoscience events. Implications for future research and classroom practice are discussed. FACTORS UNDERLYING STUDENTS’ CONCEPTIONS OF DEEP TIME: AN EXPLORATORY STUDY By Kim A. Cheek A thesis submitted for the degree of Doctor of Philosophy School of Education Durham University 2010 ii Table of Contents TITLE PAGE i TABLE OF CONTENTS ii LIST OF TABLES viii LIST OF FIGURES x DECLARATION xii STATEMENT OF COPYRIGHT xii ACKNOWLEDGEMENTS xiii CHAPTER ONE: A CONTEXT FOR THE RESEARCH STUDY 1 1.1 Importance of the concept of deep time 2 1.2 History of our understanding of deep time 5 1.3 What does it mean to say someone possesses a concept of deep time? 9 1.4 What should students of different ages understand about deep time? 12 1.5 Origins of the study 17 1.6 Statement of the problem 19 1.7 Aims of the study 20 1.8 What this thesis is not 23 1.9 Concluding remarks 28 CHAPTER TWO: REVIEW OF THE LITERATURE 29 2.1 A context for a review of the literature 29 2.2 Conventional time 31 2.2.1 Piaget and the development of a concept of conventional time 34 2.2.2 Succession research since Piaget 38 2.2.3 Duration research since Piaget 45 2.2.4 Montangero and diachronic thought 54 2.2.5 Summary of the research on conventional time 62 iii 2.3 Large numbers 64 2.3.1 An understanding of number and relationships among numbers 65 2.3.2 The role of a unit 78 2.3.3 Summary of the research on large numbers and the role of a unit 85 2.4 Subject matter knowledge and concept acquisition 86 2.4.1 A model for the role of subject matter knowledge in concept 87 acquisition 2.4.2 How experts and novices use subject matter knowledge 92 2.4.3 Summary of research on subject matter knowledge 101 2.5 A framework for the review of deep time conceptions research 101 2.5.1 Conventional time concepts and a concept of deep time 102 2.5.1.1 Succession in deep time 102 2.5.1.2 Duration in deep time 104 2.5.1.3 Summary of succession and duration in deep time 105 2.5.2 Large numbers and a concept of deep time 106 2.5.3 Geoscience content knowledge and a concept of deep time 107 2.6 Literature on conceptions of deep time 109 2.6.1 Research on succession in deep time 110 2.6.2 Research on duration in deep time 131 2.6.3 Summary of the literature on conceptions of deep time 136 2.7 A model for a concept of deep time 138 2.8 Other factors that influence the stability of the “stool” 140 2.9 Summary and conclusions 142 CHAPTER THREE: METHODOLOGY OF THE RESEARCH 145 3.1 A pragmatist approach to quantitative and qualitative research methods 145 3.2 Rationale for research methods for this study 153 3.2.1 Why task-based semi-structured interviews? 155 3.2.2 Issues in the use of interviews 157 iv 3.2.3 Issues that must be addressed in the development of task-based 160 interviews 3.2.4 Why middle school, high school, and university students? 161 3.2.5 Why a cross-age study? 162 3.3 Development of the instrument: The role of preliminary interviews 163 3.4 The interview protocol 169 3.4.1 Succession items 171 3.4.2 Duration items 174 3.4.3 The interview procedure 184 3.5 The sample 185 3.5.1 University participants 186 3.5.1.1 Institution A 186 3.5.1.2 Institution B 189 3.5.2 Eighth and eleventh grade participants 191 3.6 Methods of data analysis 193 CHAPTER FOUR: RESULTS OF THE STUDY 195 4.1 Conventional time and a concept of deep time 195 4.1.1 Tasks exploring understanding of succession 196 4.1.1.1 The before and after relationship 197 4.1.1.2 Simultaneity along with the before and after relationship 197 4.1.1.3 What do these students understand about succession? 202 4.1.2 Tasks exploring understanding of duration 203 4.1.2.1 Results of duration tasks 204 4.1.2.2 Explanations given for responses 207 4.1.2.3 Categorisation of responses by strategy employed 214 4.1.2.4 Development of strategies 216 4.1.2.5 What do these students understand about duration? 218 4.1.2.6 Application of understanding of duration to a 220 stratigraphic sequence v 4.1.3 What can we say about how conventional time impacts an 229 understanding of deep time? 4.2 Large numbers and a concept of deep time 231 4.2.1 How timelines were categorised 233 4.2.2 Students who possess a poor understanding of smaller numbers 240 4.2.3 Students whose understanding of large numbers is insufficient to 245 deal with deep time 4.2.4 Students whose understanding of large numbers is sufficient to 252 deal with deep time 4.2.5 Anomalous data 260 4.2.6 What do the timelines indicate these students understand about 264 large numbers? 4.3 Geoscience content knowledge and a concept of deep time 267 4.3.1 Geoscience content knowledge and fossil succession 268 4.3.2 Geoscience content knowledge and succession of geoscience and 276 historical events 4.3.3 Geoscience content knowledge and duration 289 4.3.3.1 Duration of events questionnaire 290 4.3.3.2 Timeline 3: Geoscience content knowledge and duration 294 with large numbers 4.3.3.3 Comparison of Timeline 3 with duration of events 298 questionnaire 4.3.4 How does geoscience content knowledge impact how these 300 students understand deep time? 4.4 Relationships among the three “legs” of the “stool” 302 4.4.1 Comparison of duration animations with the numeric timelines 302 4.4.2 Comparison of Timeline 3 with Timeline 4 304 4.5 Summary of the results: Is there a “typical” 8th, 11th grader, or university 312 student? vi CHAPTER FIVE: DISCUSSION 315 5.1 Succession 317 5.1.1 Succession and conventional time 318 5.1.2 Succession and geoscience content knowledge (fossil sequencing) 320 5.1.3 Succession and geoscience content knowledge (card sort) 324 5.1.4 Succession and large numbers 331 5.2 Duration 333 5.2.1 Duration in conventional time via animations 335 5.2.2 Application of duration to a stratigraphic sequence 338 5.2.3 Duration and geoscience content knowledge (Timeline 3) 340 5.2.4 Duration and geoscience content knowledge (duration of events 342 questionnaire) 5.2.5 Duration and large numbers 344 5.3 Is performance in one area a good predictor of performance in another? 346 5.4 Evidence of other factors affecting an understanding of deep time 347 5.5 Students’