1. 11/8/2015 Nature of Science

2. 11/8/2015 Nature of Science 1. What is science? 2. What is an observation? 3. What is a fact? 4. Define theory. 5. Define law. 6. What is a hypothesis? Pre-Test

3. 11/8/2015 Nature of Science Tentative, uncertain Cannot solve all kinds of problems One way of knowing about the universe Attempts to explain natural phenomena in natural terms Deals only with facts and the operation of natural laws Involves rigorous, systematic use of observations and logic to attempt to disprove or invalidate possible solutions, not prove them Science

4. 11/8/2015 Nature of Science Most fundamental concept is CAUSE AND EFFECT Deals only with natural (physical) universe Based on repeatable observable facts Relies on observation Conviction that natural processes have natural causes Second major characteristic is hypothetico-deductive thinking Science is a thoroughly human enterprise Characteristics

5. 11/8/2015 Nature of Science Observation refers to the ability to sense a natural phenomenon through careful, analytical, attention e.g.-noticing that your cat wakes you at 5:30 AM every morning is an observation. Various tools used Makes use of all human senses Observation

6. 11/8/2015 Nature of Science Facts = verifiable, repeatable observations i.e.- information that has objective reality arrived at through observation Science demands that there be general agreement on the facts e.g., it is a fact, (it is true) that, if I drop a bowling ball from the roof of this building, it will fall to the ground. This act can be repeated many times, by many individuals, with all agreeing on the result It is a fact that a gallon of water weighs 8.34 lbs Facts

7. 11/8/2015 Nature of Science 1. What is the most fundamental characteristic of science? 2. What are the other characteristics of science? 3. What is a fact? 4. Give an example of a fact. 5. What does the term, observation, mean? 6. Give an example of an observation. Quiz

8. 11/8/2015 Nature of Science Most fundamental concept of science is that of cause and effect: i.e., A causes B; Scientists are never satisfied with simply describing events in the natural world; strive to show relationships between events and to explain them Cause & Effect? From http://www.702communications.com/~ahill/Parent.html Cause & Effect

9. 11/8/2015 Nature of Science Inductive reasoning - specific to the general Deductive reasoning - general to the specific Deductive reasoning starts with general rule or premise, then make conclusion about something specific. Hypothetico-Deductive Thinking e.g: All turtles have shells The animal I have captured is a turtle I conclude that the animal in my bag has a shell

10. 11/8/2015 Nature of Science Inductive reasoning - specific to the general Making conclusion based on set of empirical data. If I observe that something is true many times, concluding that it will be true in all instances is a use of inductive reasoning. e.g.: All sheep that I’ve seen are white All sheep must be white Most scientific discoveries made using inductive reasoning The Raven Paradox debates the philosophical problems with this method but it is still accepted as a superior method. Hypothetico-Deductive Thinking

11. 11/8/2015 Nature of Science 1. What is inductive thinking? 2. Give an example of inductive thinking other than the one used above. 3. What is deductive thinking? 4. Give an example of deductive thinking other than the one used above. Quiz

12. 11/8/2015 Nature of Science Data - information about natural world gathered directly/indirectly through senses Quantifiable Greatest accuracy possible Experimenter’s choice Verifiable & verified Data

13. 11/8/2015 Nature of Science Laws - describes what nature does under certain conditions, and will predict what will happen as long as those conditions are met. (http://science.kennesaw.edu/~rmatson/3380theory.html) Theories - comprehensive explanation of an important feature of nature; supported by many facts gathered over time; allow scientists to make predictions about as yet unobserved phenomena. Objective - all data considered Rational - clear, logical connections between data while forming theory Highest level of reliability in science Theories & Laws

14. 11/8/2015 Nature of Science Debate and revision of ideas in science is a natural process. Debate is NOT evidence that a theory is fatally flawed.

15. 11/8/2015 Nature of Science 1. What are data? 2. Explain the difference between data and information. 3. Explain the difference between a law and a theory. 4. Why does the statement, “It’s just a theory”, cause misunderstanding of science by nonscientists? Quiz

16. 11/8/2015 Nature of Science No rigid, lock-step series of procedures always followed by every scientist in every situation Many methods used to do science as long as they meet the criteria described above Methods used depend upon type of science done Methods Repeat nightly 1000x until it has become your mantra:

17. 11/8/2015 Nature of Science Theoretical - employs mathematical models and abstractions in an attempt to explain natural phenomena. Experimental – practical testing of hypotheses via controlled, natural, observational experiment

18. 11/8/2015 Nature of Science Methods always involve the following: Hypothetico-deductive reasoning Careful observation of natural events Asking questions Forming hypotheses (testable assumptions) Testable, verifiable, falsifiable Inference from observations Remember: never proven, never right or wrong Data either support, fail to support, or inconclusive Confirmed hypotheses become points of information within a theory. Testing hypotheses

19. 11/8/2015 Nature of Science Careful Observation From http://www.marinebiodiversity.ca/shark/english/derby_mako.jpg

20. 11/8/2015 Nature of Science Asking Questions From http://i.treehugger.com/files/th_images/dropping-knowledge-d-05.jpg

21. 11/8/2015 Nature of Science Scientists then often form a hypothesis Possible explanation for an event or set of observations, a testable assumption Developed by making an inference from a set of specific observations to reach a general conclusion e.g., you observe that each time you spray an ant, a bee, or a wasp, with Raid™, it dies. From these observations you infer that Raid kills all insects Based on repeatable observation, experience and literature research

22. 11/8/2015 Nature of Science A hypothesis is not an educated guess. Beginning scientists often write down their hypothesis in "if....then" format e.g- since cockroaches are insects, you could write, "If I treat cockroaches with RAID™, then they will die” Not right or wrong; data either support or fail to support Can never, under any circumstances, be proven Must be testable and falsifiable.

23. 11/8/2015 Nature of Science 1. Explain the difference between a scientific law and a scientific theory. 2. Describe a scientific hypothesis. 3. What is a control, and how many are there in a good scientific experiment? 4. What is a control group? 5. Explain the difference between controlled, natural or quasi-, and observational studies. Quiz

24. 11/8/2015 Nature of Science Make predictions based on hypotheses, test the predictions Test these predictions through experiments Mental, mathematical, computer model, physical Variables (conditions that change) Independent vs. dependent Controls (conditions held constant) Positive & negative Control experiment Control group Experimental group Repeatable and repeated

25. 11/8/2015 Nature of Science Can be mental, mathematical, computer simulations, or physical procedures Have variables, or conditions that can change When possible, only one condition changed, and in specific way by the scientist referred to as the independent variable Doing this increases the certainty that the observed results are caused by this variable When possible, changes in the dependent variable must be quantified Dependent variable = condition that changes as result of manipulation of independent variable Scientific Experiments

26. 11/8/2015 Nature of Science To be considered scientifically valid, experiments must be repeatable and repeated i.e.-must be possible to do the experiment over, preferably by different scientists, yielding similar results each time To further strengthen cause-and-effect relationship, all other variables need to be controlled. Good experiments contain at least one experimental group and at least one control group In the experimental group, the chosen variable is changed while all other conditions are held constant In the control group, all conditions are held constant.

27. 11/8/2015 Nature of Science Draw conclusions based upon results Deductive reasoning, i.e., reasoning from the specific to the general Communicate results to other scientists and to public

28. 11/8/2015 Nature of Science List the characteristics of a valid scientific experiment. Quiz

29. 11/8/2015 Nature of Science ….for now.