What is Science?

 The goal of science: is to investigate and understand the natural world, to explain events and use those explanations to make predictions.

 1. Observation – gather info in an orderly way.  2. Collect data  Quantitative – numbers  Qualitative – descriptive  3. Data allows us to make inferences – interpreting our data using our prior knowledge.  4. Hypothesis – An explanation for a set of observations. “educated guess”

 Test your observation skills… 

 Designing an experiment  Ask a question  Form a hypothesis (prediction & reason)  Set up a controlled experiment  manipulated – variable that is changed  responding – variable that reacts to the change  controlled – variables (need 2) that stay the same  Record and Analyze Results  Draw a conclusion  Publish/Repeat experiment

 Discuss:  Design a way to experimentally find the “best” chocolate chip cookie.  What are your variables?

 Validity: How well a test measures what it is supposed to measure.  Something in the procedure you did  Reliability: How well you are able to get stable & consistent results.  “R” is for REPEAT.

 Back to the chocolate chip cookie experiment.  How would you make it reliable?  How would you make it valid?

 Biology (and all sciences, really) seek solutions to real-world problems.  A constraint is a problem your real-world solution might encounter.  A limitation is why that constraint is limiting you.

 Some bears are getting into trash cans at campgrounds near the forests. The park rangers plan to trap & relocate these bears to solve the problem of these bears getting into the trash. Describe constraints (other than cost) that park rangers could encounter when trapping/relocating the bears. Describe how each constraint is a limitation.

 When evidence from numerous investigations builds up a hypothesis may become so well supported that we call it a theory  Not as it is used colloquially “just a theory”… gravity is “just a theory”  Theory – WELL TESTED explanation that unifies or explains a broad range of observations.  Example: Why are marsupials (kangaroo) only found in Australia? Both the theory of plate tectonics and the theory of evolution work together to answer this question.