Scientific Method

1. Scientific Method

2. Science • Science is something you know and something you do. • Body of knowledge and getting answers about the natural world. • Pure science seeks to answer questions about how the natural world works. • Applied science uses the information from the pure sciences to solve problems • Ecology is the the study of how living things interact with each other and their nonliving environments.

3. Pure or Applied • Applied • Pure • ecology • biology • environmental science • physics • medicine • engineering • chemistry

4. Scientific Method • Observation • Questions • Hypothesis • Experiment and Data Collection • Summarizing Data • Communicating Results

5. How it Begins • All science begins with observations. • Use your senses: see, hear, smell, feel (not taste) • Use instruments: X-rays, thermometers, etc. • Lead to Questions • Why, how, what if. . . Asking interesting questions is the basis of all science. • A Hypothesis is a testable explanation for the question or observation. • A possible answer that we can investigate

6. Good Design • Need two groups • Experimental group • Control group • Only change one thing (variable) • Everything else must be kept the same. Why? 1

7. Studying Warblers • Theory predicted that two species with identical ecological requirements would compete and push each other out. • Observation: 5 species of very similar warblers live together in a northeastern spruce forest. • Question: • Hypothesis:

8. Ways to Test a Hypothesis • Observation • Benefits: In the field (natural environment), can observe natural behavior • Limitations: Hard to control experiment, hard to collect quantitative data • Experiment • Benefits: Can set-up and control experiment, focus on one thing to collect data from. • Limitations: Not natural environment, can’t replicate all cases. • Modeling : using computer programs to predict • Benefits: predict future or what if events, don’t disturb environment. • Limitations: Must include as many factors as possible in model, hard to measure all components to include, lots of assumptions must be made.

9. Setting up an Experiment • Hypothesis is tested under controlled conditions. • Two groups are studied • Only one variable changed • All other variables are controlled • Control group show what would happen with no treatment (normal) • Why only change one thing?

10. Why Control • Control groups show us that the variable we are changing is truly causing the result. • If we see the same result in both the control and experimental group what does that mean? • If we change more than one variable we can’t tell which one is causing the result.

11. What to do with Data • Data is most useful when it has been organized and presented in easy to understand ways. • Three main ways to organize data • Tables • Graphs (line and bar for example) • Pie Charts • Easier to see trends when presented

12. Examples • Observation: • Question: • Hypothesis: • Experiment:

13. And then . . . • Scientist want to share their results . . . • To advance other discoveries • To gain credit for their work • Publish results in scientific journals • Peer reviewed • Searchable • Science builds on science • Learn from past experiments • Change and update results as new information is available