The Nature of Science 1-1 What is Science? 1-2 The Scientific Method

Fossil in the Butte In the southwest corner of Wyoming, there is a flat-topped mountain called Fossil Butte. A fossil of a fish was found near the top of Fossil Butte in a rock formation that is about 50 million years old. Fossils of other kinds of fishes, as well as turtles, have been found at Fossil Butte. The land around Fossil Butte is dry, and the Pacific Ocean is more than 1000 km away. How could fossils of sea- dwelling animals have formed at Fossil Butte?

Yum You left out an apple on your table. After 5 days, the apple decays and you notice little worms coming out of the apple. Hmmm… how did the worms get there?

Worms and apples Prior knowledge –What do you know about worms and apples? What did you observe? –Qualitative –Quantitative What do you infer? How can you come up with an experiment?

Designing an Experiment Section 1-2 Flowchart Go to Section: State the Problem Form a Hypothesis Set Up a Controlled Experiment Record Results Analyze Results Draw a Conclusion Publish Results

Control versus Variable Conduct two ALMOST identical experiments Control –Item that is the SAME in BOTH experiments Variable –Item that is the DIFFERENT in BOTH experiments

In any experiment Is it better to have fewer controls or fewer variables? Less variables more control

Steps of the Scientific Method 1.Observing and stating the problem –You have to notice it before you think about it 2.Form a hypothesis –Take a guess to explain it 3.Test the hypothesis –Create an experiment with controls and variables 4.Record and analyze data 5.Form conclusion –Does you data backup your hypothesis? 6.Replicate the work –Can you do it again and get the same conclusion?

OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat. HYPOTHESIS: Flies produce maggots. PROCEDURE Controlled Variables: jars, type of meat, location, temperature, time Manipulated Variables: gauze covering that keeps flies away from meat Uncovered jarsCovered jars Several days pass Maggots appearNo maggots appear Responding Variable: whether maggots appear CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur. Section 1-2 Figure 1-8 Redi’s Experiment on Spontaneous Generation Go to Section:

Gravy is boiled.Flask is open. Gravy is teeming with microorganisms. Gravy is boiled. Flask is sealed. Gravy is free of microorganisms. Section 1-2 Figure 1-10 Spallanzani’s Experiment Go to Section:

Broth is boiled.Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Section 1-2 Figure 1-11 Pasteur’s Experiment Go to Section:

The BOTTOM Line In the end science can only explain the natural world We use the scientific method to explain the natural world We use experiments to observe, interpret, and explain the natural world

In class assignment READ Ch 1-2 and Ch 1-3 Answer all the questions –SA 1-2 and SA 1-3 Turn in to the front basket On a separate sheet of paper –After you are done, create an 8 window cartoon experiment using the scientific method –Color and label

Homework Using the steps of the scientific method, finish your cartoon experiment Return all books properly Study for quiz Have a good day