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1 How do we know what we know?

1• How do we know what we know?

Observations

&

The Scientific Method

(Hypothesis-Prediction Approach)

1 An Example Close to Home @ Cedar Crest

• Giggle-Fits After Lunch

1 If the Giggle Fits Do Not Reflect Your Company

What did you have for lunch???

• Pasta with Italian Dressing

• Pasta with French Dressing

• Salad with Blue Cheese Dressing

• Vanilla Cone with Sprinkles

• A Controlled Experiment

1 The Scientific Method

• Make observations

• Ask questions

• Form hypotheses

• Make predictions

• Test predictions

1 The Scientific Method

• Make observationsGee, I’m having unusual giggle fits after lunch each day.

• Ask questionsWhy am I having giggle fits?

• Form hypothesesI am having these fits because I am eating pasta with Italian dressing every day.

1 The Scientific Method

• Make PredictionsIf I eliminate pasta with Italian dressing from my lunch, I will no longer have giggle fits.

• Test PredictionsDo not consume pasta with Italian dressing for several days. Do you still have giggle fits?

1 Distinguishing Science from Non-Science

“Scientific methods are the most powerful tools that humans have

developed to understand how the world works. Their strength is founded on the

development of the hypotheses that can be tested… If you understand the

methods of science, you can distinquish science from non-science.”

Source: Your textbook (Purves, et al.), p. 13.

1 Diversity of Life?

Figure 1.8 A Provisional Tree of Life

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Figure 1.2 All Mammals Have Similar Limbs