Nature of Science

1. Nature of Science August 2014 Bio X

2. From the Solutions Lab • What do you observe? Look for patterns in the “data.” • What do you infer each solution to be? • What evidence do you have for your inference? • How confident are you in your answer? • What would make you more sure?

3. How is what you were doing like science? • Based on evidence/data (empirical) • You made inferences from observations • Your ideas are never 100% sure and could change with more data (tentative) • You worked with others (collaborative) • Your ideas were checked by each other (peer review) • You used your background knowledge to guide your inferences (subjective)

4. Nature of Science • Empirical – based on data, testable • Tentativeness – subject to change, never certain, 100% • Observation vs. Inference – inferences make sense of observations, consistent with patterns in data • Subjectivity – each person’s background knowledge & scientific conceptual framework impact how they view data and even their observations • Collaborative – scientists work with each other, within individual labs as well as by building on each other’s findings throughout the world • Peer Reviewed – scientists make their findings public (presentations or publications) and findings are reviewed by other scientists Science is limited – it can only address questions about things that can be observed.

5. What Is Science? • Latin word scientia = knowledge • Search for knowledge • Something is science if it can be experimentally tested over and over • It is objective and unbiased

6. Limitations of Science • Science cannot answer questions regarding judgment • Questions involving vague or intangible concepts (superstitions, “bad luck”) cannot be answered by science • Many times, scientific experiments don’t yield answers but lead to more questions.

7. Types of Science • Pure science- done to learn more and gain knowledge (for the sake of knowing) • Ex. Experiment used to learn how a new drug works • Applied science- puts knowledge to use • Ex. Using the drug to treat an illness

8. Branches of Science • Biology • Zoology • Chemistry • Physics • Astronomy • Botany • Hydrology • Physiology • Biochemistry • many many more!

9. How Do We Study Science? • Make an initial observation • Formulate a hypothesis • Design an experiment • Test hypothesis (conduct experiment) • Collect Data • Analyze Data • Draw conclusions • Communicate findings

10. Initial Observation • Curiosity is the beginning of experimentation • The scientific method generally begins with an unexplained observation about nature. • Observations lead to questions

11. Forming A Hypothesis • Possible answer to a scientific question • TESTABLE! • From the hypothesis made, scientists can make predictions that logically follow the hypothesis that was made

12. Experiment Design • Plan out how you will test your hypothesis • Performing the Experiment: • Designate a control group • Designate an experimental group • Independent Variable • Dependent Variable

13. Performing an Experiment • Control: standard to which you measure experimental results to • Independent Variable: factor that is being tested • Dependent Variable: responding variable (“depends” on the independent variable) • Constant: factor(s) that remain the same in an experiment.

14. Collecting & Analyzing Data • Quantitative Data vs. Qualitative Data • Quantitative: measurements (numbers) • Must determine if results are reliable (errors?) • Compare results • Charts/Tables • Graphs (Bar graphs, Line graphs, Pie Charts) • Qualitative: descriptions • Ex.: descriptions of behavior, color changes, etc.

15. Drawing Conclusions • Biologists analyze their tables, graphs & charts to determine if a hypothesis is supported or not • Scientists make inferences from data • Inference: conclusion made on the basis of facts and previous knowledge rather than on direct observations • Scientists communicate their findings

16. Theory vs. Law • Theory: Highly tested and confirmed idea that can explain a great amount of data. • Ex: Theory of evolution, Cell theory • Law: Statement of fact that explains an action or set of actions. It is generally accepted to be true and universal • Ex: Law of gravity