U1L2 - Scientific Knowledge

Unit 1 Lesson 2 Scientific Knowledge

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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.


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.



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.



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.



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.



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.



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.


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.



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.



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.



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.


U1L2 - Scientific Knowledge

Education

Transcript of U1L2 - Scientific Knowledge