scientiﬁc method for ecological...

ScientificMethod forEcologicalResearch

E. David FordCollege of Forest Resources, University of Washington

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© E. David Ford 2000

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First published 2000

Printed in the United Kingdom at the University Press, Cambridge

Typeset in Garamond 11/13pt [vn]

A catalogue record for this book is available from the British Library

Library of Congress Cataloguing-in-Publication Data

Ford, E. D. (Edward David)

ScientiWc method for ecological research/E. David Ford.

p. cm.

Includes bibliographical references and indexes.

ISBN 0 521 66005 X (hardcover)

1. Ecology – Research – Methodology. 2. Science – Methodology.

I. Title.

QH541.2.F66 2000

[email protected]@2 – dc21 99-30065 CIP

ISBN 0 521 66005 X hardback

ISBN 0 521 66973 1 paperback

Contents

Preface xv

Acknowledgements xviii

1 Component processes of ecological research 1

Summary 11.1 Questions about the process of scientiWc research 21.2 ScientiWc methodology 41.3 Distinction between progress and process in scientiWc research 51.4 Section I: Developing an analytical framework 61.5 Section II: Making a synthesis for scientiWc inference 81.6 Section III: Working in the research community 91.7 Section IV: DeWning a methodology for ecological research 101.8 Synopsis of methodological problems facing a new researcher in

ecology 111.9 How to use this book to develop your research skills 111.10 Further reading 13

Introduction to Section I: Developing an analyticalframework 15

2 Five processes of research planning 19

Summary 192.1 Introduction 202.2 Process 1: DeWning a research question 21

2.2.1 Origins and types of research questions 212.2.2 Analysis of questions 24

2.3 Process 2: Applying creativity to develop new research ideas 282.4 Process 3: Ensuring the proposed research has relevance to prior

scientiWc knowledge 292.5 Process 4: Ensuring the proposed research is technically feasible and

can be completed with available resources 322.6 Process 5: Determining how conclusions can be drawn 33

2.6.1 Developing a data statement: An example 342.6.2 Using statistics to illuminate the problem, not support a

position 382.7 Further reading 40

3 Conceptual and propositional analysis for definingresearch problems 41

Summary 413.1 Introduction 413.2 Constituents and properties of theories 423.3 Conceptual and propositional analysis 56

3.3.1 Phase One: Identifying the principal issues 573.3.2 Phase Two: Classifying concepts according to their status in

the progress of research 583.3.3 Phase Three: Examining the complete research procedure 65

3.4 Representing theories as networks 653.5 What can be gained from a conceptual and propositional

analysis? 673.5.1 Deciding whether you can assume something or must

investigate it 693.5.2 Understanding logical relationships between diVerent pieces

of knowledge 693.5.3 Assessing how complete a theory is 703.5.4 Knowing when to start practical investigation 70

3.6 Conclusion 713.7 Further reading 71

4 Development of a research plan 73

Summary 734.1 Introduction 734.2 Process 1: DeWning a research question 74

4.2.1 The Wrst description 744.2.2 Initial development of a theory for the problem 764.2.3 First deWnitions 774.2.4 First consideration of Process 4: Ensuring the proposed research

is technically feasible and can be completed with availableresources 78

4.2.5 First consideration of Process 2: Applying creativity to developnew research ideas 79

4.2.6 Continuation of Process 1: DeWning a research question 804.3 Process 4: Ensuring the proposed research is technically feasible and

can be completed with available resources 854.4 Process 3: Ensuring the proposed research has relevance to prior

scientiWc knowledge 934.5 Process 2: Applying creativity to develop new research ideas 944.6 Process 5: Determining how conclusions can be drawn 954.7 Steel’s comments on the planning process after completing her

Master’s thesis 1014.8 Further reading 102

viii contents

5 How theories develop and how to use them 103

Summary 1035.1 Introduction 1035.2 Development of a theory from a simple postulate: Late-Quaternary

vegetation change in central Alaska 1085.2.1 Stage 1: Rejecting a simple postulate 1085.2.2 Stage 2: Exploring for spatial and temporal changes 1115.2.3 Stage 3: Introducing axioms from tree ecology 1135.2.4 Stage 4: Increasing the precision of the theory 1145.2.5 Stage 5: Working towards explanations that are coherent with

meteorological theories 1155.2.6 Assessment of theory development 116

5.3 Practical application of a theory: Hybridization in Wsh species 1185.4 Development, properties, and use of ecological theories 1275.5 Further reading 129

6 The art of measurement and experiment 131

Summary 1316.1 Introduction 1316.2 Principles of measurement for new concepts 1336.3 Experimental analysis of ecological systems 1366.4 Planning an analytical experiment: An example – control of

photosynthesis rate of Pinus strobus trees 1426.4.1 Results from an improved measurement technique 1426.4.2 Observing an anomaly 1436.4.3 Making a conceptual analysis of the problem 1466.4.4 Constructing multiple postulates 1496.4.5 Choosing a postulate to study 1526.4.6 DeWning the experimental conditions 1566.4.7 Developing a measurement 1586.4.8 Designing treatment application, replication, and controls 1596.4.9 Investigating ancillary processes to aid interpretation and

assessment 1646.5 Whole-system analytical experiments 1646.6 Discussion 1656.7 Further reading 167

7 Methods of reasoning in research 169

Summary 1697.1 Introduction 1707.2 Principles of propositional logic 1717.3 The use of propositional logic in ecological research 1787.4 The hypothetico-deductive method and use of falsiWcation in

scientiWc reasoning 1837.5 An exercise in choosing between postulates expected to be true and

postulates expected to be false 1877.6 How to decide whether to attempt conWrmation or falsiWcation 189

ixcontents

7.7 Using contrasts 1957.8 Causality 1967.9 A strategy for constructing theory using multiple working

postulates 2007.10 Discussion 2017.11 Further reading 202

8 Assessment of postulates 203

Summary 2038.1 Introduction 2048.2 ReWning postulates using exploratory analysis 2068.3 Developing a scientiWc procedure and set of measurements 2108.4 Satisfying the logic required for statistical inference 219

8.4.1 Constructing and assessing a statistical hypothesis 2268.4.2 Completing the data statement 231

8.5 Discussion 2318.6 Further reading 234

9 Individual philosophies and their methods 235

Summary 2359.1 Introduction 2359.2 Initial assumptions 239

9.2.1 Teleology 2399.2.2 Parsimony 2429.2.3 Holism and reductionism 2439.2.4 Teleology, parsimony, and reductionism in ecology 244

9.3 First formalizations of methodology 2519.3.1 Empiricism 2519.3.2 Rationalism 2549.3.3 Empiricism and rationalism in ecology 256

9.4 Uncertainty about the objectivity of method 2649.4.1 Criticism 2649.4.2 Relativism 2659.4.3 Statistical experimentalism 266


Introduction to Section II: Making a synthesis forscientific inference 269

10 Properties and domains of ecological concepts 279

Summary 27910.1 Introduction 28010.2 DeWnition and purpose of ecological concepts 28110.3 The domain of functional and integrative concepts 28810.4 Example of use and development of ecological concepts and their

domains 291

x contents

10.4.1 Developing deWnitions of natural and functional concepts 29110.4.2 Using functional concepts to deWne an integrative concept 29310.4.3 Making inference about an integrative concept 300


11 Strategies of scientific research in ecology 309

Summary 30911.1 Introduction 31011.2 Does ecological science advance through recurring revolutions? 311

11.2.1 The ecosystem revolution 31311.2.2 The progress of normal science 31511.2.3 Did a revolution terminate the paradigm? 31911.2.4 How useful is Kuhn’s theory for understanding research

strategy? 32311.2.5 ScientiWc inference and the ecosystem paradigm 324

11.3 The methodology of scientiWc research programs 32711.3.1 A strategy for continuous assessment 32711.3.2 The components of a scientiWc research program 32811.3.3 Top-down and bottom-up forces in population and

community ecology 33011.3.4 Criticisms of the methodology of scientiWc research

programs 34211.4 The investigation of domains 34411.5 Discussion 34811.6 Further reading 349

12 Use of mathematical models for constructingexplanations in ecology 351

Summary 35112.1 Introduction 35212.2 Dynamic systems models 353

12.2.1 Simple diVerential equation models 35312.2.2 Using dynamic systems models to predict the unexpected 35912.2.3 Fitting dynamic systems models to ecological systems 363

12.3 Statistical models of dependence 36812.3.1 Modeling dependence in time series as a stochastic process 36912.3.2 Assessing a stochastic time series model as an explanation 375

12.4 Systems simulation models 37812.4.1 Objectives, theory, and model design 37912.4.2 Calibration and validation 38212.4.3 Assessing using multiple outputs 385


xicontents

Introduction to Section III: Working in the researchcommunity 393

13 Scientific research as a social process 395

Summary 39513.1 Introduction 39613.2 Social inXuences and social structures 397

13.2.1 The balance between norms and counternorms in scientists’behavior 397

13.2.2 Cooperation and competition between individualscientists 403

13.2.3 Fraud and misconduct in science 40713.2.4 The role of gender in scientiWc debate and discovery 410

13.3 Creation and use of scientiWc literature 41213.3.1 Constructing a scientiWc paper 41313.3.2 Peer review 41513.3.3 Problems of quantity and quality 42113.3.4 Literature citation and its analysis 423

13.4 Developing and using explicit standards of criticism to constructobjective knowledge 425


14 Values and standpoints and their influence onresearch 431

Summary 43114.1 Introduction 43114.2 Standpoints in science, management, and policy 433

14.2.1 Scientists’ standpoints 43314.2.2 Managerial standpoints 439

14.3 Reviewing and funding scientiWc research 44314.3.1 Research proposals and their peer review 44414.3.2 ScientiWc research with policy implications 452

14.4 Science, scientists, and society 45514.5 Discussion 46214.6 Further reading 463

Introduction to Section IV: Defining a methodologyfor ecological research 465

15 The methodology of progressive synthesis 467

Summary 46715.1 Introduction 46815.2 The standpoint of Progressive Synthesis 468

15.2.1 Types of acceptable explanation 46915.2.2 Certainty in scientiWc inference 472

15.3 Principles of Progressive Synthesis 474

xii contents

15.3.1 Principle I: Continuous application of just and eVectivecriticism 475

15.3.2 Principle II: Precision is required in deWning axioms andconcepts, postulates and data statements, and theories 476

15.3.3 Principle III: Explicit standards must be used to examine therelation between theory and data 478

15.4 Components of the method of Progressive Synthesis 48115.4.1 Component 1: Analyze the question and seek to use

contrastive techniques to focus the research 48215.4.2 Component 2: Expect to use diVerent techniques of

investigation as theories develop and new types of question areasked 487

15.4.3 Component 3: ReWne both measurement and conceptdeWnitions 488

15.4.4 Component 4: Specify the new synthesis resulting from theresearch 488

15.4.5 Component 5: DeWne explanatory coherence of the synthesisto make a scientiWc inference 493


16 Criticisms and improvements for the scientificmethod in ecology 497

Summary 49716.1 Introduction 49716.2 Criticisms of ecological research 499

16.2.1 There has been lack of progress in ecology 49916.2.2 No general theory has emerged 50016.2.3 Ecological concepts are inadequate 50316.2.4 Ecologists fail to test their theories 505

16.3 Suggestions made for improving ecological research 50616.3.1 Suitable research objectives for ecology 50716.3.2 Forms of reasoning that should be used 51116.3.3 The relation between concepts and theories 511

16.4 Ideals and strategy of Progressive Synthesis 51416.5 Further reading 518

Appendix: Suggestions for instructors 521

References 525

Glossary 541

Author index 555

Subject index 559

xiiicontents

Component processes ofecological research

Summary

Ecologists starting research for the Wrst time have many questions about thescientiWc method. This chapter gives examples of these questions and classiWesthem into three groups: those concerned with the analytical process ofresearch; those concerned with the special problems of ecology, particularlyhow we synthesize knowledge and develop ecological theory; and thoseconcerned with the social aspects of research. The chapter describes how thesegroups of questions will be answered in successive sections.

section i

Developing an analytical framework. A logical framework is required forresearch. Assumptions must be clearly stated as axioms, and questions must beformed as postulates, i.e., statements that can be investigated and then classiWedas true or false, or assigned a probability. This framework is the foundation forthe research you do and the basis for making scientiWc inference.

section ii

Making a synthesis for scientiWc inference. Ecological and environmentalresearch present special problems of scientiWc methodology. Ecological systemsare open to multiple inXuences and vary in ways that limit the types ofinvestigation used and the generality of scientiWc inference that can be made.Some important concepts have to be deWned by a theory.

section iii

Working in the research community. Social interactions inXuence the scientiWcmethod. Science is, in part, a social activity that can inXuence how, and what,problems are researched.

section iv

Progressive Synthesis is deWned as a methodology for developing ecologicaltheories and examining how coherent they are as explanations.

1

A distinction is drawn between what scientists do in research (the progressthey make) and how it should be done (the processes that should be used).Progress comes from continuous dialogue between our theories about theworld and the measurements we make that result in the synthesis of new orimproved theories. To energize this dialogue, we use four processes: creativ-ity, deWnition, assessment, and, most important, critical analysis. Criticalanalysis is a foundation for creativity because it reveals what may be wrong ordeWcient in deWnitions and assessments and what must be reconstructed.

1.1 Questions about the process of scientific research

ScientiWc discovery has a particular satisfaction. The joy of discovery – ‘‘Hereis something new!’’ – is heightened by the realization that what has beencreated through research increases or changes the knowledge developed byother scientists. Furthermore, a new discovery may make it possible to solve apractical problem. These components, a discovery that is relevant to otherknowledge and that may have practical value, make science an exciting andrewarding creative activity.

Many ecologists starting research have questions about the scientiWcmethod and how to apply it, whether it really works for ecology, and how thescientiWc community functions collectively in making discoveries (Table 1.1).Those who gave the questions for Table1.1 were embarking on research inbasic ecology, the conservation and management of natural resources, andenvironmental sciences. Despite the diverse nature of their research topics,the questions show repeated concerns about three components of the researchprocess:

(1) How to develop a conceptual and logical framework for discovery andassessment (Questions 1–21, Table 1.1). Many students have a practicalquestion they wish to answer or a subject they wish to research.However, it can require considerable analysis to deWne how a piece ofresearch should proceed, what should be measured, how investigationsshould be carried out, and what process should be used for makingscientiWc inference.

(2) How to approach the particular diYculties associated with ecological andenvironmental research (Questions 22–25, Table 1.1). Ecological sys-tems present particular diYculties to the research scientist. Their varia-bility can make them diYcult to sample, but this variability is notsimply a nuisance. It is a fundamental characteristic of ecologicalsystems! For example, at the organism and population levels, geneticvariability and plasticity in development are inherent characteristics. Atthe community or ecosystem level, diVerences in local environment orhistory can make an ecological system unique in an important way that

2 component processes of ecological research

Table 1.1. Questions asked by ecology students at the start of a graduate course inthe scientiWc method. These questions are complete and as they were written bystudents. Questions 16 and 17 contain misuses of the terms ‘‘hypothesis’’ and‘‘prove’’. See Chapters 3, 7, and 8 for correct deWnitions and examples of use

I. Questions about research planning and the scientific method1. How can I come up with a question?2. I have ideas and topics but I don’t have a project.3. How can I refine a question so that an answer can be obtained?4. I have a project. Can I find an innovative way to look at the problem? Can I find

a way where others have not?5. When starting research how do we know what analogies to use? How to get

new ideas?6. Am I making a significant contribution to the body of knowledge?7. I have my project – but have I missed anything out?8. How will I know whether I am duplicating other research?9. How will I know whether my project is relevant or significant to a theory or a

practical question, or just a stupid idea?10. How can I conduct a literature review? How will I know what research is going

on, what has been done? What about research in a foreign language?11. How will I know whether my project is too big or too small?12. How can I confine the question so that it is a Master’s topic and not a lifetime

of study?13. How will I know when to stop (as an individual) given the cyclical nature of

science?14. How do I limit the project so that it can be finished in two years?15. How will I analyze my data and write my thesis? How will I know what to

conclude? Have I got there?16. You make a hypothesis, and then you try to prove it. What if it is incorrect?17. We start by trying to prove a hypothesis, but we end up trying to fit a new

hypothesis to the data?18. Will I collect bad data, or data insufficient to answer the question?19. Some questions have answers. Some problems are exploratory. How do you

present the exploratory work? This is difficult because the scientific cultureexpects answers.

20. What types of control or experimental design will I need?21. How can I interpret my results in an unbiased way so that I do not massage my

results to fit any preconceived viewpoint?

II. Questions about research in ecological science22. How can I ask the right question and measure the right things? How can I

sample a whole ecosystem? How can I avoid samples being influenced byunusual events?

23. How do we extrapolate from research on a limited system (laboratory or fieldplot) to give an understanding of a whole ecosystem?

24. How can I find a place (site) where a question can be answered? There may bedifficulty matching a proposed theory with practical reality.

25. Which techniques are the best for measuring the response of a tree toenvironmental factors? For example, the development of a bioassay?

31.1 questions about the process of research

Table 1.1. (cont.)

III. Questions about working in the research community26. Can I get funded?27. Funding!28. I am interested in funding and individual recognition.29. How do I choose a committee that will give me a broadly based opinion?30. How can I get my committee to stop suggesting things to do?31. What if my committee steers me incorrectly?32. How can I analyze, integrate, and present to the outside world?33. How can I choose a research topic of value? Or if you have chosen a research

topic how can you persuade someone to fund it?34. How can I make research relevant to current topics of theoretical and practical

interest?

must be taken into account in a research study. Because of this variabil-ity, research in ecology can involve two phases of activity: (a) discove-ring a phenomenon or process and developing a theory that explains it,and (b) understanding how important that phenomenon or process is indiVerent situations.

(3) How to work within the scientiWc and natural resource managementcommunities (Questions 26–34, Table 1.1). Supervisors, major profes-sors, and associated faculty and colleagues inXuence a student’s researchthrough their distinct research perspectives, which the student mustidentify and weigh. Local, state, or national agencies frequently fundecological and environmental research, and social factors inXuence whoreceives grants or contracts from them. In addition, much ecologicalresearch investigates practical problems of environmental managementwith the objective of providing solutions. Almost inevitably, any pro-posed solution will have an economic or social impact on someone ormay run counter to his or her ideals. Even the possibility that this mayhappen can inXuence what research is proposed and how it is conduc-ted.

1.2 Scientific methodology

This book presents a methodology for scientiWc research.

methodology

A system of techniques of investigation, methods for applying the techniques,and general principles for how the methods should be used in scientiWc inquiry.


Techniques of investigation used in research, such as experimentation, survey,or constructing computer models, must be applied using methods that ensurean eVective process of scientiWc reasoning. Principles, such as the continuoususe of criticism and being explicit in deWnitions and methods of assessment,must be used consistently for all techniques and methods.

The Wrst objective of this book is to provide a structure for the process ofscientiWc reasoning and research planning. The second is to illustrate particu-lar problems in ecological research that determine how diVerent techniques ofresearch can be used and show how careful we must be in our methods ofusing these techniques. The third is to discuss how social inXuences can aVectscientiWc research. In this respect ecological research faces some particularlydiYcult challenges when a problem is important for resource or environment-al management.

1.3 Distinction between progress and process in scientificresearch

The foundation for answering the questions in Table 1.1 is to recognize thatscientiWc research has two parts. (1) What scientists do – the techniques theyapply to solve problems and make progress. (2) How scientists think – thethought processes scientists use in analyzing a problem.

(1) What scientists do. Scientists analyze problems and then make investiga-tions and/or conduct experiments to discover new information. Theyorder and explain this information in a synthesis by producing theoriesof how the world works. Theories are the result of a dialogue betweenwhat we think we know (our previous theories), and what we see ormeasure in the world (our data). It takes eVort to become proWcient inparticular techniques of investigation, e.g., ecological Weld experiments,vegetation survey and analysis, and to understand how theories areconstructed with information obtained by using them. Not surprisinglythe research questions we choose, and the way we analyze them, may bestrongly inXuenced by the techniques of investigation we have mas-tered. The theories we construct, or rate as most valuable, may be biasedtowards information obtained from the techniques of investigation withwhich we are most familiar. The challenge we face is that theory anddata are interlinked (Fig. 1.1), and this circular nature of investigationcan strongly inXuence what we Wnd out – even when we think we areapproaching new problems. This is why problem analysis is so import-ant at the start of research.

(2) How scientists think. The repeated dialogue scientists conduct betweenTHEORY and DATA requires critical analysis and creativity. DeWni-tion and assessment must be in constant interaction: we deWne our ideas

51.3 distinction between progress and process

Fig. 1.1. The cycle of scientificinvestigation. Althoughscientists use data to assesstheories, the type of data theycollect is determined by thosetheories. Analyzing a scientifictheory so that it can bequestioned by data is a majorchallenge for the scientist.

as a theory, develop new ideas from the theory, assess those ideas usingmeasurements, and redeWne the theories in a new synthesis. However,the interaction between deWnition and assessment must be pushed,prodded, and cajoled by critical analysis. Critical analysis is the funda-mental process we must continually apply to make deWnitions exact andunambiguous, and assessments unbiased (Fig. 1.2).

Criticism is an essential foundation for creativity. This may at Wrst seemcounterintuitive; we often associate criticism with destruction, the opposite ofcreativity. But discovering something new may Wrst require realizing that acurrent theory or set of observations is defective or inadequate in some way.

Scientists themselves are most concerned with what they do in research.They tend to take the thought processes that drive their research for granted.Except for statistical testing, which is one component of assessment, theseprocesses are less discussed than the results of scientiWc research. Mostscientists learn the use of these thought processes indirectly by observingresearch progress. This book emphasizes the advantages of being explicitabout those processes. Ecology is an interesting, but diYcult, subject. Manyof its valuable concepts either require many measurements to deWne them orcan not be measured directly but are deWned by theory. This book deWnes amethod of reasoning for analyzing ecological concepts, how a new synthesis ismade following research, and how that synthesis can be assessed.

1.4 Section I: Developing an analytical framework

Doing research is a diVerent activity from learning by course work. Thisbecomes apparent when research planning starts. Section I of this bookprovides answers to Questions 1–21 (Table 1.1) in the form of a description


Fig. 1.2. Critical analysis andcreativity must motivate thecycle of scientific advance.Critical analysis must ensurerigor in definition of problem,theory, and assessment of data.Creativity can occur duringboth theory definition and dataanalysis and is frequentlystimulated by critical analysis.

of the process of research that can be followed, particularly at the planningstages when the task is analysis of the problem and how to solve it.

Chapter 2 discusses in detail Questions 1–21 (Table 1.1) as they relate tothe Wve processes of research planning: (1) deWning a research question; (2)applying creativity to develop new research ideas; (3) ensuring the proposedresearch has relevance to prior scientiWc knowledge; (4) ensuring the proposedresearch is technically feasible and can be completed with available resources;and (5) determining how conclusions can be drawn.

Chapter 3 details the key to research planning: making a conceptual andpropositional analysis by deWning three types of knowledge (Fig. 3.1): axioms,what we assume we know; postulates, what questions we have but stated in apropositional form so they can be classiWed as true or false using the research;and data statements, which deWne the data needed to classify the postulates astrue, false, or acceptable with a certain probability. The hardest work can bein determining exactly what can be taken as an axiom and what must beresearched as a postulate. The key to this is deWning the individual conceptsthat make up axioms and postulates.

Chapter 4 illustrates conceptual and propositional analysis with anexample, an investigation of the use made by small mammals of piles ofwoody debris cast up alongside a river after Xoods. Conceptual and proposi-tional analysis is a progressive process that may take weeks or months tocomplete. This very active phase of research brings together published infor-mation in the scientiWc literature, information known about a Weld site orspecies, and knowledge of what can be done practically.

Chapter 5 presents a Wrst discussion of the development and use ofecological theories to illustrate the importance of analysis. Though we contin-ually seek generalities in our theories, we must modify them to investigatespeciWc situations. Development of a theory to describe the post-glacial

71.4 i : developing an analyt ical framework

invasion of Alaska by tree species shows how both a theory, and the logic usedto investigate it, can change. An investigation of interbreeding betweenrelated species of anadromous Wsh shows the diYculties in using a theorydeveloped for one system as the basis for analyzing another one, even thoughthe species are related.

Chapter 6 illustrates problems that can arise in making measurements andplanning experiments. The properties of measurements to be made must beanalyzed for their eYciency in representing the concept, their accuracy, andtheir precision. The example presented, concerning the control of photosyn-thesis rate of foliage on a mature Pinus strobus tree, illustrates how to proceedwhen encountering an unexpected result. It shows the importance of havingcompeting postulates in research and of making more than one measurementof a new concept.

Chapter 7 introduces methods of reasoning used by scientists in theirresearch and diYculties associated with them. Deduction and the rules oflogic are descibed and the general inductive approach followed in research isillustrated. Conditions when it is possible to falsify a postulate are described,and why that can be an important procedure, and the logic for havingcompeting postulates, rather than just one, is illustrated. In ecology wedepend upon causal reasoning; diVerent types of causes are illustrated.

Chapter 8 distinguishes between scientiWc and statistical inference. Thetests and procedures that statistical science has produced are based on statisti-cal theories whose assumptions must be understood before they can beapplied. This is particularly important for ecological and environmentalresearch, where some assumptions used in statistical theory may not hold inimportant ways. This chapter emphasizes the need for exploratory analysis toestablish whether, and how, a statistical test can be constructed.

Chapter 9 concludes Section I by describing diVerent individual scientiWcphilosophies and how these inXuence research by motivating diVerent typesof analysis of scientiWc problems. Philosophies are neither right nor wrong,but are sets of ideas about how research is, or should be, conducted. Aphilosophy can bring both strengths and weaknesses to a research investiga-tion. Some philosophies do make assumptions about the nature of what willbe found out in ecology.

1.5 Section II: Making a synthesis for scientific inference

Ecology is characterized by use of concepts such as ecosystem, community, andpopulation and properties such systems have such as diversity, stability, orpersistence. These concepts can not be measured directly; we have to constructtheory to deWne them. In Chapter 10 these are classiWed as integrativeconcepts and we build theory about them using both functional concepts, thatdeWne how organisms and the environment interact directly, and natural


concepts, that deWne organisms and environmental factors or conditions.This classiWcation acts as a heuristic for the development of ecologicalknowledge. We also have to recognize that our theories about integrative andfunctional concepts can take time to develop and, explicitly, that any theorymay not be universally true. For example, a theory that explains high and lowspecies diversity between examples of one type of ecosystem may not explainit between examples of another. We should not simply assume generality inthe theories we propose. The idea that theories have domains of application isintroduced in Chapter 10 and is used to illustrate how theories may developand be reconciled with other, aparently conXicting, theories.

Ecological theories, particularly those deWning integrative concepts, arecomplex and they can not be rejected by single, critical, investigations. Weseek to know whether such theories are good explanations. In Section II adeWnition is made of what constitutes an explanation, and the idea ofexplanatory coherence for making an assessment is introduced; examples aregiven in each chapter of the section.

The use scientists make of ecological theory, and their concern about howto develop it, determine research strategy. Chapter 11 discusses some diVer-ent research strategies described by philosophers who have studied science.They are used to illustrate what is critical in the diVerent tasks of establishinga new theory and stimulating the development of a growing theory. Thechapter discusses further applications of the conceptual classiWcation given inthis section and the development of explanatory coherence in diVerentsituations.

DiYculties in both the analysis of ecological systems, and the use ofintegrative concepts for making a synthesis, have led to the use of quantitativemodels. Chapter 12 illustrates assumptions of diVerent types of model anddiscusses the diYculties those assumptions cause for using models to repre-sent, or even replace, theory.

1.6 Section III: Working in the research community

In this book, attention is paid to the relationship between what we do asscientists and the social environment in which we work. A critical approach isthe essential requirement for a research scientist; but this can be stronglyinXuenced by colleagues, research sponsors, and sometimes environment andnatural resources managers. Scientists must be aware of those inXuences andtheir consequences. Socially imposed restrictions on criticism and innovationcan be the most diYcult problem a young scientist encounters. This bookstresses the need for scientists to develop the logical basis for their research andin this way to become an integral part of a community of scholars. Social andeducational factors, however, can inXuence attempts to become part of acommunity.

91.6 i i i : working in the research community

Chapter 13 discusses the types of social inXuence in science and their eVecton planning and conducting research and in preparing scientiWc papers forpublication. The social diYculties that may be encountered in research arenot simply something extra to be coped with. They are due to the very natureof research as an imprecise activity – where recent results are still insecure andwe can not be certain of the best way ahead.

Chapter 14 illustrates particular diYculties faced by doing ecologicalresearch in an applied context where a natural resource is managed or impactson people’s economic or cultural well-being. Decisions about environmentalpolicy and the management of natural resources are made from particularstandpoints. ScientiWc research can inXuence these decisions but the ways thismight occur most eVectively still seem uncertain and can be inXuenced by thestandpoints of scientists, managers, and policy-makers. Examples are givenwhere scientiWc analysis was central to a particular resource managementpolicy, and where it was excluded. In both cases major changes becameinevitable: in the Wrst as society’s demands changed; in the second whenenvironmental catastrophes occurred.

1.7 Section IV: Defining a methodology for ecologicalresearch

At appropriate points in the Wrst three sections there are discussions of thestrengths and weakness of well known techniques of investigation. A numberof innovations are introduced for analyzing ecological research problems andmaking synthesis of results to develop new theory. Chapter 15 is an integrateddescription, presented as a methodology for ecological research, of ProgressiveSynthesis. This methodology has three principles:

There should be continuous application of just and eVective criticism.Precision is required in deWning axioms and concepts, postulates anddata statements, and theories.Explicit standards must be used to examine the relation between theoryand data.

These principles are applied to a method for reasoning designed for makinginference about ecological concepts and theories. This method focuses onhow change can take place through concept deWnitions and the constructionof theory, use of comparisons, and development and assessment of scientiWcexplanations.

Chapter 16 reviews criticisms of ecological research: that there has beenlack of progress, no general theory has emerged, ecological concepts areinadequate, and that ecologists fail to test their theories. These criticisms arebased upon ideals about what types of knowledge we should be Wnding out inecology and what are the most appropriate techniques of investigation. They


have frequently been formed through observing sciences with diVerent typesof problem from those encountered in ecology. In contrast, ProgressiveSynthesis focuses on the method of reasoning that should be used in ecologi-cal research and how appropriate techniques of investigation can be applied.

1.8 Synopsis of methodological problems facing a newresearcher in ecology

(1) Frequently the processes of scientiWc research are not made explicit tograduate students (Stock 1985, 1989). This book tackles this deWcitdirectly by illustrating how to reWne a question into a program ofmeasurement and methods for making scientiWc inference.

(2) You have to master multiple processes to make progress in research.Simultaneously, you have to deWne what has been done, devise ques-tions and research to answer them that will advance knowledge, con-struct investigations that will actually work, and most likely learn whatprocedures of statistical inference to use. This complete process ofscientiWc research is diYcult the Wrst time you attempt it: as when ridinga bicycle, you must learn to balance, watch the road ahead, and pedal,all at the same time. This book shows how to deWne a scientiWcobjective, even for complex problems in ecology, and this providesdirection that enables you to balance your diVerent activities.

(3) As an undergraduate, you may have read original scientiWc papers andlearned to debate opposing views. In research, you come closer to thecenter of discussion and debate, where opposing views have not beenreconciled, and sometimes are not even fully deWned, so no reconcili-ation may yet be possible. Then arguments are Werce, and social factorscan play an important role in deciding who follows what argument.This book deWnes these issues to help you to identify the ideals thatindividuals and organizations may have and how those ideals may aVectresearch objectives, methods, and interpretations.

(4) Ecology has some unique problems in the method of scientiWc reason-ing for its important concepts. When ecologists express diVerencesabout the value of particular techniques of investigation they use, it isnot always clear whether the resultant debates are about the scientiWcdetails or the philosophies behind their use of particular techniques.This book shows why diVerent types of research problem requirediVerent techniques of investigation and presents a methodology forreasoning about ecological concepts and theories.

1.9 How to use this book to develop your research skills

The challenge of ecological research is not just in what you must learn but also

111.9 how to use this book

in how you must think. The focus in this book is on developing a criticalattitude about a scientiWc problem and constructing a procedure for assess-ment. The book will have the most practical value if you can follow foursuggestions:

(1) Adopt a scientiWc question you wish to investigate. Establishing the logicalbasis for an investigation and determining what type of scientiWcinference should be made are best learned by applying the techniques ofSection I to a real problem. Do not be concerned if your ideas are notyet crystal-clear – this book is designed for you! The techniques pres-ented help to sharpen general ideas into speciWc research plans.

(2) Practice the development of a ‘‘logic for discovery’’ with other students. Setup small discussion groups with three or four other students working onsimilar research problems. It is most important to learn the art ofcriticism, particularly self-criticism, without being personally destruc-tive either to your ideas or to those of others. It is essential to learn, inthe planning stage, that an idea that you had was incomplete and toknow what it feels like to improve that idea through further work, or toreject it and adopt another. You must learn how to treat an idea not aspart of your own identity but as something to be turned over, poked at,and examined to see how it Wts with other ideas.

(3) Do not be apprehensive about, or dismissive of, philology or philosophy.Philology is the science of language. Much science is about deWningterms and much progress in ecology is made by developing deWnitionsof concepts. Concepts start imprecise, become more precise as a re-search plan takes shape, and then sharpen even more by the end of theresearch. This process of deWnition and redeWnition requires work – andextensive critical analysis. This book deliberately sets out to give you aframework for deWning ideas, and deciding how certain you are abouttheir deWnition. Words are all we have with which to express ideas inscience. So being exact in science means being exact about how wedeWne and use words. A philosophy is a system of thinking about things.We all have philosophies, though we may not think of them as such.The philosophy we hold can have a major inXuence on the way that weWrst cast a scientiWc problem – and it is frequently our philosophy thatwe have to question rigorously. This book examines diVerent philos-ophies held by scientists and how they inXuence the approach toresearch.

(4) Understand the strengths and weakness of science as a social activity. Part ofdeveloping as a scientist is to associate with groups of people withinterests in similar problems and frequently with similar approaches tosolving them. For students starting research, ‘‘socialization’’ into aparticular scientiWc group is very important if you are to absorb a


detailed understanding of problems and techniques. However, becausethe basis of good science requires developing a critical approach, youmay sometimes Wnd yourself challenging the very ideas, and ideals(philosophies), that the members of the group you have joined holdmost dear.

1.10 Further reading

Mahoney (1976) gives a strong, and sometimes vehement, description of thelogical diYculties of the scientiWc method and, particularly, scientists’ failureto confront them. Stearns (1986, 1987) advises graduate students how toproceed in their research; Huey (1987) ampliWes and debates that advice. Therelationship between research student and supervisor is discussed in a publica-tion of the Council of Graduate Schools (Anon. 1990), and lists of practicalsuggestions are given for both students and supervisor. Smith (1990) gives aguide for graduate students in the sciences to most practical things graduatestudents must do and be involved in and Locke et al. (1993) describe andanalyze eVective dissertation proposals.

The two questions ‘‘How can we Wnd things out?’’ and ‘‘How do we knowwhether our answers are correct?’’ are the problems of developing a heuristicand an assessment procedure. Through his description of the types of theoryconstructed and whether, and on what grounds, they have been accepted,McIntosh (1980) shows how methodological problems associated with heu-ristics and assessment have been central to the development of ecology. Hisaccount is valuable as a background for understanding why some questions inecology have been studied repeatedly and apparently not resolved.

131.10 further reading

scientiﬁc method for ecological...

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