Biology is the study of the phenomena of life, and biological scientists- researchers, teachers, and students-observe living systems and organisms, ask questions, and propose explanations for those observations. Scientific investiga- tion is a way of testing those explanations. Science assumes that biological sys tems are understandable and can be explained by fundamental rules or laws. Scientific investigations share some common elements and procedures, which are referred to as the scientific method. Not all scientists follow these procedures in a strict fashion, but each of the elements is usually present. Science is a creative human endeavor that involves asking questions, making observations, develop- ing explanatory hypotheses, and testing those hypotheses. Scientists closely scrutinize investigations in their field, and each scientist presents his or her work at scientific meetings or in professional publications, providing evidence from observations and experiments that supports the scientist's explanations of biological phenomena. In this lab topic, you will not only review the process that scientists generally use to ask and answer questions about the living world, but you will develop 2 LAS Scientific Investigation the skills to conduct and critique scientific investigations. Like scientists, you will work in research teams in this laboratory and others, collaborating as you ask questions and solve problems. Throughout this laboratory manual, you will be investigating biology using the methodology of scientists, asking ques- tions, proposing explanations, designing experiments, predicting results, col- lecting and analyzing data, and interpreting your results in light of your hypotheses. EXERCISE 1.1 Questions and Hypotheses This exercise explores the nature of scientific questions and hypotheses. Before going to lab, read the explanatory paragraphs, answer the questions, and then be prepared to present your ideas in the class discussion. Lab Study A. Asking Questions Scientists are characteristically curious and creative individuals whose curios- ity is directed toward understanding the natural world. They use their study of previous research or personal observations of natural phenomena as a basis for asking questions about the underlying causes or reasons for these phenomena. For a question to be pursued by scientists, the phenomenon must be well defined and testable. The elements must be measurable and controllable. There are limits to the ability of science to answer questions. Science is only one of many ways of knowing about the world in which we live. Consider, for example, this question: Do excessively high temperatures cause people to behave immorally? Can a scientist investigate this question? Temperature is certainly a well-defined, measurable, and controllable factor, but morality of behavior is not scientifically measurable. We probably could not even reach a consensus on the definition. Thus, there is no experiment that can be per- formed to test the question, and this question cannot be pursued through the scientific process. Which of the following questions do you think can be answered scientifically? 1. Are domesticated dogs as smart as wolves? 2. Will drinking milk from arthritic goats reduce HIV levels in infected individuals? 3. Do urban honey bees prefer processed sugar over flower nectar? 4. How effective are marigold and rosemary as insect repellants? 5. Should governments prohibit distribution of GM food during severe. famine? How did you decide which questions can be answered scientifically?