1 Nature of Science

Resources

1. Freeman et al. 2024. Biological Sciences (8th ed.), pp. 10–14 (Chapter 1.6).
2. Video and information links on course canvas page.
3. Voves, K.C., T.S. Mitchell, and F.J. Janzen. 2016. Does natural visual camouflage reduce turtle nest predation? The American Midland Naturalist. 176 (1): 166-172.
4. Citations Interchapter, pp. 17–20.

What is Science?

Inspiration for scientific discovery can come from a variety of places. Scientists are curious people who observe something they find interesting, ask questions about what they’ve observed, and then dive deeply into the subject to learn as much as they can.

Scientists follow a particular method for asking questions and designing experiments:

1. Ask a question.
2. Conduct background research (has someone else already answered this question?).
3. Use the initial questions along with what was learned from the background research to construct a hypothesis.
4. Design an experiment to test the hypothesis.
5. Carry out the experiment (often requires troubleshooting along the way).
6. Collect and analyze the data from the experiment.
7. Draw conclusions (do your data support the hypothesis?).
8. Compare experimental results to others published from similar research.
9. Communicate results to others, ideally in a peer-reviewed publication.
10. Very often, following this process, scientists come up with many new questions. What is learned in one experiment is often incorporated into the background information used to design new experiments to help the researcher answer new questions.

In today’s lab, we will be closely examining the process of science to learn how to ask good questions, develop a hypothesis, design an experiment, and read scientific literature. These steps are where the scientific process begins – and much like learning how to use scientific equipment properly, they are important components that need to be learned and practiced. In the next few labs, you will utilize these basic scientific skills repeatedly. Taking the time to learn the foundations now will set you up for a successful semester. Today in lab you will get an opportunity to practice some of these steps and to get some feedback from your classmates and your TA. This lab will require you to work closely with a lab partner to discuss questions, brainstorm ideas, and work through some parts of the scientific process. Don’t be afraid to ask questions and show your curiosity!

 

Step 1 – Ask a Question

The scientific process starts when a scientist asks a question. Inspiration for these questions can come from anywhere (wondering why different people like different foods, watching animals interact with each other, observing human behavior, wondering why leaves change color in the fall, etc.). To help you start thinking creatively, we have selected a few short videos for you to choose from. Watching these videos will lead you to come up with some interesting questions! Use the links on canvas or use one of the lab laptop computers and find the folder labeled Week 2 Videos inside the Biology 2120L folder on the desktop. This file contains four short videos. Select one of the four (described below) that you and your lab partner find most interesting and watch the video in its entirety. After watching the video, answer the questions below.

1. 1. Termite World (a video clip about why termite mounds look the way they do)
   2. Butterfly Eggs and Caterpillar Survival (a video clip about the interactions between a species of butterfly, ant, and wasp)
   3. Venus Fly Traps (a video clip about how some carnivorous plants lure and trap their prey)
   4. Crab Shell Exchange (a video clip showing how hermit crabs find new shell homes)

1. Which video did you choose?
2. What did you find most interesting about the video?
3. What is one new thing you learned from watching the video?
4. How could you learn more about the topic of this video?
5. Based on what you learned in the video, write down two research questions that you would be interested in learning more about.
6. Could the questions you asked above be investigated and tested (provided you had unlimited time and resources)? How would you test them?

Step 2 – Develop a Hypothesis

Now that you know how to ask a question, let’s work on how to develop a hypothesis. Having a clear hypothesis is essential to designing an effective experiment. As is the case in many scientific endeavors, there is some important terminology to familiarize yourself with in order to successfully understand this portion of today’s lab. Match the list of terms below with their definitions.

____________________________: A statement declaring a tentative answer to a question based on observations in nature. It often includes predictions based on stated assumptions so that it can be tested.

____________________________: A factor or condition that is changed by the scientist.

____________________________: A factor or condition that is observed and measured by the researcher, to see how it changes in response to a variable manipulated by the scientist (see above definition).

____________________________: A step-by-step description of how the experiment will be run so that other scientists could replicate it.

____________________________: Treatment in the experiment in which the scientist has changed the independent variable to measure an effect.

____________________________: Treatment in the experiment that the scientist intends to compare to the other treatments to test if there is a real effect of the independent variable. Determining this treatment is straightforward in some experiments and can be difficult in others, depending on the protocol and variables. Sometimes a reference standard is used.

When you have finished the matching activity, your TA will provide you with a question card that you can use to complete the rest of this activity. This activity is designed to help you learn about the structure and writing of hypotheses. For the purpose of this exercise, background information should be limited to what you already know about the subject of your question or a very brief Internet search on the subject. When you develop hypotheses in the future, you will be expected to complete background research to help educate yourself in the effort of writing an effective hypothesis. Read your question carefully, and then use it to complete the following activity:

1. Re-phrase the research question you’ve been provided into a hypothesis. Note that hypotheses are typically formatted in the following way:

“If [I do this], then [this will happen] .”

This allows you to pose a question and make a prediction. Your prediction should not be open- ended. If you expect something to change, it is important that you describe in your hypothesis how you expect it to change. Simply stating something will change is not sufficient.

 

2. If you were to carry out an experiment to test this hypothesis, you would need to develop a protocol. Prepare a brief protocol that you could use to carry out this experiment.
3. What would be your independent variable?
4. What would be your dependent variable?
5. What would be your control?
6. Why is a control necessary?
7. What kind of data would you need to collect in order to test your hypothesis?
8. How would you analyze your data in order to determine the results of your experiment?
9. What do you predict would be the outcome of your experiment?

Step 3 – Understanding Scientific Literature

This section of today’s lab activity will help you to navigate reading and understanding primary scientific literature. One very critical step in the scientific process is to clearly communicate findings to other scientists and to the public. Scientists follow a rigorous process of publishing their work in peer evaluated scientific journals. That means that other scientists evaluate their work before the information is published and presented to a wider public audience. This evaluation helps determine if the methods used in the study are sound and makes sure there was not any bias inherent in the design of the experiment. Peer scientists are able to ask questions and request additional information about the study. Articles that do not pass the robust review process are not published. It is important to note that every journal has its own review process and its own set of standards required for publication.

We have selected a journal article for you to read and evaluate for this part of the lab activity. The article we selected was authored by researchers here at Iowa State University. This is one example of great research being conducted at your university! This particular article was selected because it is straight-forward and easy to read, which makes it a good way to begin learning how to read scientific literature. Learning to read primary literature for the first time can be challenging! It can take a lot of practice to feel comfortable. Take your time reading, make sure you follow the steps below, and ask your partner and TA any questions you have.

The article we’ve chosen is: “Does Natural Visual Camouflage Reduce Turtle Nest Predation?” by Kameron C. Voves, Timothy S. Mitchell, and Frederic J. Janzen.

The full citation for this article is:

Voves, K.C., T.S. Mitchell, and F.J. Janzen. 2016. Does natural visual camouflage reduce turtle nest predation? The American Midland Naturalist. 176 (1): 166-172.

This article has been placed onto the desktop of the laboratory laptop computers in the Nature of Science folder and can also be found on Canvas. Open the article to read and discuss it with your lab partner. Follow the activity below as you read through each section of the paper and answer the associated questions.

1. Read the Introduction

• Identify the hypothesis in this paper. Write it below.

 

• What organism was at the focus of this study?

 

• What is the meaning of the word crypsis?

 

2. Read the Methods

• What is the meaning of the word depredated?

 

• The authors of this study recruited a number of “observers” to rate photographs of nests. What criteria did they use to select these observers?

 

• Why is it important to have more than one observer?

 

• Why is it important for the scientists to include lots of detail in their methods section?

 

• What kinds of data did the scientists collect?

 

3. Read the Results

• How many total turtle nests were included in the study?

 

• Of those, how many remained intact?

 

• How many were depredated?

 

• What was the predation rate?

 

4. Read the Discussion

• Did the researchers’ results show that camouflage was a predictor of nest survival? Were more camouflaged nests less likely to be predated?

 

• The authors of this study provided a list of factors beyond nest cues that may have had an effect on painted turtle nest predation. List 2 of these factors in the space below.

 

• Did the results of this study support the authors’ predictions? Did the results support their hypothesis, or force them to reject their hypothesis?

 

• If the data collected by a researcher forces them to reject their initial hypothesis, does that mean their research was “bad”? “unnecessary”? “worthless”? Why or why not?

 

• Can valuable information be obtained from studies in which hypotheses are rejected?

 

5. Look over the References

• How many references did the authors include in their paper? Why is it important to include so many?

 

• If you wanted to learn more about a different study that the authors mention in the intro (like Spencer and Thompson, 2003), how would you do so?

 

• Why is it important to cite primary literature? What is primary literature?

 

6. Citations

The Literature Cited section at the end of a paper is very important. It provides you with all of the details you would need to find the sources referenced within the paper. If you wanted to find out more about one of the studies the authors referenced, you can look it up and read about the study yourself. For more information on citations, read the Citations Interchapter on pages 17-20.

7. Read the Abstract

• What is the purpose of having an abstract?

 

• Often scientists write the abstract last, why do you think that is?

 

8. Reflect on the Content

• What is one question that you still have after reading this paper?

 

• What was the most confusing part of this paper for you?

 

Step 4: Applying What You Learned

Now that you’ve learned a bit more about the process of science, it is time to start putting your new skills to work! One of the goals of Biology 2120L is to have students practice all steps of the scientific method over the course of the semester while conducting several experiments. These experiments will be done in a group, which is intended to help you learn yet another aspect of the scientific process – collaboration. Most scientists do not conduct their research on their own – science requires people to work together to come up with their best work. Sometimes scientists work with other researchers in their own laboratories, but often those collaborations are with researchers who may be hundreds or thousands of miles away at another university or research facility, perhaps even in another country. As a result, learning to navigate how to conduct a research experiment with others is an important skill.

In addition to learning how to conduct experiments with others, it is also important to learn how to examine the literature to determine what other researchers have learned from similar experiments. Before scientists begin their research, they spend time reading through scientific papers to determine what other scientists have already done. They want to know if the experiment they want to conduct has already been done, and what the findings were. They want to know if there have been other studies with results that may contribute to the knowledge needed to design and conduct a new study to address a new question. Learning about what has already been done helps inform scientists as they form hypotheses and design new experiments.

It is important when gathering information that scientists use reliable sources they can trust. Scientists publish their work in scientific journals, which conduct a peer review before publishing any new work. That means that fellow scientists evaluate the paper, providing comments and feedback to the authors so they can make edits, provide clarification, or conduct additional studies before their work is approved for publication.

As part of a group project you will work on this semester, you will need to find peer-reviewed literature relating to your project that you will use as sources of background information. It will be a good idea to start on this early, so you have plenty of time to locate good sources of information that you can use later in the semester. Spend some time checking out the university library website and/ or Google Scholar to learn how to search for scientific papers.

1. What is a scientific journal? How do scientists publish in a scientific journal?
2. What is peer review?
3. Why should this process produce more reliable information than other information available on the Internet?

This semester, you will be assigned to a small group to work on a research and presentation project. For this project, you and your group will be assigned one of the topics of the class experiments in the next few weeks. Besides planning out and performing the experiment for the week that you are assigned, you will also research that topic in the scientific literature and present on it to the class. You will give a short class presentation on your experiment during Week 8. This will allow you to practice the scientific process from start to finish.