A rationale for problembased learning in ecology: theory and practice

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A rationale for problem-based learning
in ecology theory and practice

• Dr. Malcolm McElhone, Department Humanities and
  Sciences, University of Wales College, Newport
• http//ecospace.newport.ac.uk
• E-mail malcolm.mcelhone_at_newport.ac.uk

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A rationale for problem-based learning
in ecology theory and practice

• What are the aims of teaching second year
  ecology?
• What is the rationale for teaching students to
  think scientifically
• How is problem based learning used to achieve
  these aims?
• What are the outcomes?

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Aims of the ecology module

• Science is distinguished from non-science in a
  rough and ready way and scientists seem to accept
  some theories rather than others.
• Attempt to heighten the students' level of
  critical awareness of how science need not
  concern itself with certainty yet be quite
  capable of distinguishing good theories from bad
  ones, and truth from falsity.

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Aims of the ecology module

• To appreciate the difference between science and
  non-science and to understand why certain
  theories have withstood criticism and others have
  not.
• To improve the students' knowledge of competing
  theories regarding plant succession and community
  structure.
• To examine weaker and stronger ecological
  theories

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Aims of the ecology module

• To improve the students' ability to negotiate,
  criticise, communicate and improve their
  knowledge of a chosen ecological theory
• To initiate original thinking necessary for the
  solution of the ecological problems.
• Introduce students to the excitement of science

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Previous Observation
Problem
Belief
Insight
Informal private phase
Existing theory
Working hypothesis
Formal Hypothesis
Formal test phase
Prediction
Corroboration
Falsification
Comparison with observation
From Rigler and Peters (1995)
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What factors influence lichen distribution and
abundance? Brainstorming !
Physical factors e.g Light intensity
Competition
Lichen distribution
Characteristics of bark
Grazing
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Strong inference problem orientated (sharp
exclusions)
1. Devise alternative hypotheses
2. Devise a crucial experiment to exclude one
of the hypothesis
Y
N
3. Carry out experiment to get a clean result
N
Y
4. Repeat procedure
1. Devise terminative hypotheses
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. Our trouble is that when we make a single
hypothesis, we become too attached to it. Platt
(1964, 350)

• Concise report evaluating the state of critical
  discussion
• Does the theory solve the problem?
• How can we test it?
• Has stood up to tests - evaluation of performance
• Can it predict anything with sufficient
  precision?

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What can we ask from a theory?

• Does it prohibit certain things?
• Can it be shown to be wrong?
• What ingenious tests are there?
• Can it explain more than it rivals?
• Is it a simple theory?
• Does it unify ideas?
• Is it sufficiently general?

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Creating environments wherein students can
discover knowledge problem based learning and
learning by doing

• The learner brings a base of experience to the
  problem and takes more responsibility for
  learning
• The discipline boundaries are blurred and there
  is an interconnection between theory and
  practice
• The teaching role shifts from one of instruction
  to fostering autonomous learning
• There is greater focus on communication and
  interpersonal skills

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PBL enables Students to

• Practise logical, analytical approach to
  unfamiliar situations
• Activate their existing knowledge
• Elaborate new knowledge
• Learn in the context in which it is to be used
• Learn in an integrated fashion
• Practise application of new knowledge
• Practise critical reasoning
• Practise self-directed learning
• Practise communication skills
• Practise collaboration in a team.

From Engels (1991)
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Species area relationships abstract, general,
mathematical, predictive, simple and testable.
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Species Area Curves approaches and situations
for learning.
Field work for practical activity
Short lectures for the presentation of the
problem
Students as an active inquirer
Web-based resources for improving learning
Laboratory work for identification and
statistics
Home or library for study
new
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Species richness and area development of skills
of analysis, communication and critical
engagement are all supported on the internet.
Fieldwork
Data analysis
Report writing
Identifying plants
Organising and tabulating data
Structuring the report
Sampling
Drawing graphs
Reviewing literature
Calculating a regression line
Critically engaging with ideas, methods and data
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Web-based resources for fostering the scientific
approach using problem-based learning

• Advantages of problem-based learning
• Popper's approach to problem solving simplified
• Evaluating your problem
• Initiating, planning and developing your project

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Web-based resources for fostering the scientific
approach using problem-based learning

• Review and progress
• What is understood by an ecological scientific
  theory?
• Mistakes
• Evaluating the scientific merit of your work
  desiderata of scientific theory
• Further reading

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Evidence of improved learning.
Web-based learning a methodology and a case
study involving teaching and learning ecology.
-

• Current Situation
• lecturing
• fieldwork

Unintended consequences
Recognition of impediment to learning

• Design of web page for improving learning.
• Setting of web-based exercises.

• Learning improved by
• More student control
• More flexibility
• Greater efficiency
• More supportive learning environment