1. Unit 1 Lesson 2 Scientific Knowledge
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2. Unit 1 Lesson 2 Scientific Knowledge
Florida Benchmarks
SC.8.N.1.3 Use phrases such as “results support” or “fail to support” in science, understanding that science does not offer conclusive ‘proof’ of a knowledge claim.
SC.8.N.1.5 Analyze the methods used to develop a scientific explanation as seen in different fields of science.
SC.8.N.3.2 Explain why theories may be modified but are rarely discarded.
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3. Unit 1 Lesson 2 Scientific Knowledge
Florida Benchmarks
LA The student will record information (e.g., observations, notes, lists, charts, legends) related to a topic, including visual aids to organize and record information, as appropriate, and attribute sources of information.
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4. Method Acting How do scientists choose their methods?
Unit 1 Lesson 2 Scientific Knowledge
Method Acting
How do scientists choose their methods?
Scientists plan their investigations to address a specific problem or question.
Their goal is to come up with a scientific explanation.
Each problem or question is unique and so requires a unique method and the proper tools.
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5. How do scientists choose their methods?
Unit 1 Lesson 2 Scientific Knowledge
How do scientists choose their methods?
When choosing their methods, scientists rely on the tools available.
Scientists, however, know they don’t always have the tools they need.
Some tools may be too expensive, and others may not exist.
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6. How do scientists choose their methods?
Unit 1 Lesson 2 Scientific Knowledge
How do scientists choose their methods?
Scientists also need to be creative in the ways they use their tools.
Tools are useful only if the scientists using them can interpret the data they provide.
This skill is a large part of the education of a scientist.
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7. How do scientists choose their methods?
Unit 1 Lesson 2 Scientific Knowledge
How do scientists choose their methods?
Based on the subject under study, scientists may plan to do experiments or fieldwork.
When doing experiments, scientists control different variables under precise conditions in a laboratory.
Generally, physicists and chemists do a lot of experiments.
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8. How do scientists choose their methods?
Unit 1 Lesson 2 Scientific Knowledge
How do scientists choose their methods?
In contrast, scientists doing fieldwork make observations of what is around them.
They watch, observe, and try to make sense of what they see.
Instead of controlling variables, they try to determine what variables are at work and how they relate to each other.
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9. How do scientists choose their methods?
Unit 1 Lesson 2 Scientific Knowledge
How do scientists choose their methods?
A large part of doing fieldwork is coming to understand the variables that exist.
Biologists and geologists generally do a lot of fieldwork.
Sometimes, a scientist will do fieldwork and then take a specimen back to a laboratory to do more testing.
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10. Well, Prove It! How do scientific theories become accepted?
Unit 1 Lesson 2 Scientific Knowledge
Well, Prove It!
How do scientific theories become accepted?
Some theories are quickly accepted; others are not.
A good scientific theory is one that is supported by most of the evidence and can account for new observations as they arise.
Such a theory becomes widely accepted.
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11. How do scientific theories become accepted?
Unit 1 Lesson 2 Scientific Knowledge
How do scientific theories become accepted?
At times, as new evidence is discovered, scientists may find that an earlier theory is incorrect or incomplete.
Good scientific theories often get modified but are rarely rejected.
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12. How can you know who’s right?
Unit 1 Lesson 2 Scientific Knowledge
How can you know who’s right?
The most reliable scientific information is found in professional science journals, but it may not be easy to understand.
You should be cautious of accepting scientific explanations from advertisers or anyone trying to sell you something.
When you assess any scientific claim, ask yourself if it makes sense logically and whether the results support it.
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13. How can you know who’s right?
Unit 1 Lesson 2 Scientific Knowledge
How can you know who’s right?
Remember that science does not claim to prove anything.
Science attempts to provide an explanation that agrees with the results of observation and testing.
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14. A Theory for the Birds Dinosaurs take flight
Unit 1 Lesson 2 Scientific Knowledge
A Theory for the Birds
Dinosaurs take flight
The fossil Archaeopteryx gave the first solid evidence linking dinosaurs to modern birds.
Although it had wings and feathers and may have been able to fly, it seems it was more dinosaur than bird.
It had jaws with teeth, three-fingered claws, and a tail.
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