Process of Science PowerPoint

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Critical Thinking Skills and Doing Science
Elements of the scientific method:
1. Observe patterns
2. Ask questions
3. Formulate hypotheses that make specific predictions
4. Perform experiments or observations to test hypotheses
Adapted from “Learning How To Do Science” 3/12/2011 Frontiers in Science Presentation
by Fred C. Dyer, Department of Zoology
Starting Point: OBSERVATIONS
Description of PATTERN and
PROCESS
• You see a pattern in nature
• You also observe other information
that may help you understand the
processes underlying it
• To understand processes, ask
focused QUESTIONS
Adapted from “Learning How To Do Science” 3/12/2011 Frontiers in Science Presentation
by Fred C. Dyer, Department of Zoology
Questions
Write three questions based on
your observations.
Refining questions about pattern
Sometimes it helps first to find out more details about the
thing we are trying to understand:
• Often this involves asking quantitative questions
• What percentage of times do fish jump vs. shoot?
• What is success rate for jumping vs. shooting?
• Just how accurate are the fish?
• It may also be useful to ask qualitative questions
• For example: make a detailed list of the prey types that the animal feeds
on, or the habitats where it feeds
• It will not be possible to get the information needed to answer ALL the
questions.
Adapted from “Learning How To Do Science” 3/12/2011 Frontiers in Science Presentation
by Fred C. Dyer, Department of Zoology
Answering the questions
Formulate hypotheses:
• A hypothesis is a plausible guess as to answer
• Hypotheses are in the form of statements
• Usually it is possible to generate several reasonable
hypotheses
Why do archer fish sometimes jump and sometimes shoot?
Write down at least three distinct hypotheses that would
answer that question
Adapted from “Learning How To Do Science” 3/12/2011 Frontiers in Science Presentation
by Fred C. Dyer, Department of Zoology
Testing Hypotheses
A hypothesis is a possible explanation for a phenomenon
To “explain” something means you understand the cause
What does it mean to say that A causes B?
•It means that B’s occurrence depends upon A occurring
•It also means that there is some material connection that
mediates the causal relationship between A and B
Testing a hypothesis means gathering evidence to
determine whether the hypothesis is correct.
Adapted from “Learning How To Do Science” 3/12/2011 Frontiers in Science Presentation
by Fred C. Dyer, Department of Zoology
Steps so far….
In the following example, write down:
• Observations about particular natural patterns
• Questions about the causes/explanations for these
patterns
• Hypotheses about the possible causes of the
phenomenon
• Predictions that each hypothesis makes if it is true
• An additional observation or experiment that you
could do that would allow you to test this prediction
Adapted from “Learning How To Do Science” 3/12/2011 Frontiers in Science Presentation
by Fred C. Dyer, Department of Zoology
Generalizations About Scientific Hypotheses
• A good hypothesis:
• Is consistent with other known facts about nature
• Can potentially be falsified (proven wrong)
• Uncertainty always exists:
• You can’t prove a hypothesis right, you can only fail to falsify it: other
hypotheses might make same prediction
• But you may not be able to falsify it with absolute certainty: failure to
see effect predicted by hypothesis may occur because experimental
conditions weren’t present
• Value of considering multiple hypotheses:
• There are often multiple causes for phenomena
• Considering multiple causes helps in designing experimental controls
Adapted from “Learning How To Do Science” 3/12/2011 Frontiers in Science Presentation
by Fred C. Dyer, Department of Zoology
Critical Thinking Skills
Critical thinking skills are
valuable tools that will
help students be
successful in all
aspects of their lives.
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