1.2 The Scientific Method
Learning Objectives
By the end of this section, you will be able to:
- Understand the process of scientific inquiry.
- Differentiate between questions that can and cannot be answered using science.
- between questions that can and cannot be answered by scientific practices.
- Identify the elements of the scientific method.
- Identify elements of a scientific experiment, including variables and control groups, and describe their function.
Hypothesis Testing
Biologists study the living world by posing questions about it and seeking science-based responses. This approach is common to other sciences as well and is often referred to as the scientific method. The scientific process was used even in ancient times, but it was first documented by England’s Sir Francis Bacon (1561–1626), who set up inductive methods for scientific inquiry. The scientific method is not exclusively used by biologists but can be applied to almost anything as a logical problem solving method.
Question
The scientific process typically starts with an observation (often a problem to be solved) that leads to a question. As mentioned in the previous section, science is very good at answering questions having to do with observations about the natural world, but is very bad at answering questions having to do with purely moral questions, aesthetic questions, personal opinions, or what can be generally categorized as spiritual questions. Science cannot investigate these areas because they are outside the realm of material phenomena, the phenomena of matter and energy, and cannot be observed and measured.
| Questions that can be answered using science | Questions that cannot be answered using science |
| • What is the optimum temperature for the growth of E. coli bacteria? | • How tall is Santa Claus? |
| • Do birds prefer bird feeders of a specific color? | • Do angels exist? |
| • What is the cause of this disease? | • Which is better: classical music or rock and roll? |
| • How effective is this drug in treating this disease? |
|
Let’s think about a simple problem that starts with an observation and apply the scientific method to solve the problem. Imagine that one morning when you wake up and flip a switch to turn on your bedside lamp, the light won’t turn on. That is an observation that also describes a problem: the lights won’t turn on. Of course, you would next ask the question: “Why won’t the light turn on?”
Hypothesis
A hypothesis is a suggested explanation that can be tested. A hypothesis is NOT the question you are trying to answer – it is what you think the answer to the question will be and why. Several hypotheses may be proposed as answers to one question. For example, one hypothesis about the question “Why won’t the light turn on?” is “The light won’t turn on because the bulb is burned out.” There are also other possible answers to the question, and therefore other hypotheses may be proposed. A second hypothesis is “The light won’t turn on becau