Lab 1 pre-lab.
Your task in Lab 1 will be to get familiar with your group and the scientific process. Over the next three weeks, you will conduct an animal behavior experiment on the environmental preferences of terrestrial isopods. You will analyze your results, create a scientific poster detailing your research, and discuss your results as a class. You will be reusing the skills established in this introductory unit throughout BIOL 123.
How does science work?
Science is a systematic way to gain new information about the natural world. It requires testable questions, falsifiable hypotheses, and objective measurement and analysis. Pursuit of scientific knowledge therefore requires a prescribed process, known as the scientific method. You have no doubt studied the steps of the scientific method many times. They can be described somewhat differently from source to source, but contain the same basic ideas. The figure at right contains six steps with cyclical components based on specific outcomes.
Descriptions of each step are provide below Ask a question
Questions can arise from observations in the field, in the lab, from the scientific literature (e.g., scientific posters, presentations or papers), or from pre-existing data. In this class, sometimes your question will be provided to you and other times you will get to decide what questions you want to investigate. Conduct background research
This is a literature review process, in which researchers dig deep into what is already known about their topic of choice and what questions still remain. Often, the literature review helps to refine questions and direct hypothesis formation. Background research will be provided to you in our first few labs, but you will also do some research on your own in later lab activities. Construct a hypothesis
A quality hypothesis must be testable, objectively measurable, specific, and falsifiable. It must include a prediction and potential mechanism(s) based in the literature or from previous work. You will do this often in BIOL 123. Test with an experiment
There are various approaches to research design, based on your research question. These range from purely descriptive to experimental designs, which involve manipulation of a variable or variables. Regardless of the method selected, the design should have clearly identified variables by type, and should be both valid and reliable. You will have varying levels of input on the experiments we conduct in lab. Analyze the data & draw conclusions
The methods used for analysis are largely based on the research design. In the biological sciences, analysis almost always involves the use of statistical tests and graphical representations of data. We will use several different types of statistics throughout this course. Communicate your results
This last step is essential. For our understanding of the natural world to grow, new research must be shared so others can draw on what is known to expand our understanding. Results can be communicated through technical reports, presentations at conferences, scientific posters, and manuscripts which appear in scientific journals. You will create many of these products throughout BIOL 123 |
|
Common Misconceptions.
Although the process appears fairly simple, there are several common misconceptions that can really limit your understanding of how science works:
Although the process appears fairly simple, there are several common misconceptions that can really limit your understanding of how science works:
- The method does begin by asking a question, but not one conjured from thin air. The ideas for what questions to ask come from observations in the scientific literature, or while working in the lab or field.
- After forming your question, you do not go directly to experimentation. Is you question relevant? What potential mechanisms might explain your observation? These answers are found in the scientific literature: What do we already know about this topic? What else can be explained, refuted, or supported?
- The scientific method, although often pictured in a straight line, is never linear. It involves multiple iterations or cycles depending on the outcomes.
- It is also never complete without disseminating or publishing results, because the goal is to move science forward with contributions.
- It never ends in the development of a theory, and biological theories do not one day become laws (more on this later).
|
Experimental Design.
Generating a quality hypothesis is the first step to a quality research design, but all hypotheses are not created equal. It is imperative that your hypothesis be testable, objectively measurable, specific, and falsifiable. It must be accompanied by a null hypothesis, which states what we should expect if nothing of note or interest is occurring (e.g., no difference between groups, no relationship among variables, no influence of factors) and is often though of as inverse to the proposed hypothesis. Hypotheses must also generate a prediction and contain at least one potential mechanism (i.e., the cause of your observation). Once this process is complete, the next step is to carefully design your test to best answer your question. This will sometimes involve controlled experiments, or simple data collection and analysis in the case of observational studies. First you need to identify your dependent variable(s), or DVs (the variable being tested), and independent variable(s), or IVs (the variable that may influence the test variable). Next you need to identify any confounding variables. These are variables that can effect your results if they are not eliminated or controlled. Review the "White Squirrel Scenario" in the sidebar for an example of hypothesis creation and experimental design. |
Click here to review the "White Squirrel Scenario."
|
Be sure you know the general steps of the scientific method and common misconceptions.
|
Review the example with the white squirrels and make sure you can follow the reasoning involved.
|
Be sure you know the characteristics of a quality hypothesis and associated concepts like the null, your prediction, and the potential mechanism.
|
Know the key concepts involved in experimental design including: DV, IV, and confounding variables.
|
Do you know enough about animal behavior & terrestrial isopods?
All scientific research is based in theory. Biological questions are often based in evolutionary or ecological theory, which we will explore in detail throughout BIOL 123. Our fist series of labs is based in ethological theory, which has been informed by both evolutionary and ecological concepts. Ethology is the study of animal behavior. "Imprinting" is a classic example attributed to Konard Lorenz (a founding father of ethology). Check out this short clip of wild turkeys imprinting on their adoptive dad, naturalists Joe Hutto. Information on the full documentary can found HERE.
Ethological theory has two primary components:
Ethological theory has two primary components:
- Behavioral traits can be inherited or learned. We refer to inherited or ingrained behavioral traits as innate. Organisms are born with these behaviors and practice them (as instinctual) from birth. Learned behaviors are developed over time as a result of experience and exposure to various stimuli.
- Behavior changes to achieve survival (i.e., it is adaptive). Behavioral traits follow the same patterns that govern other inheritable traits. Positive traits that increase fitness, an organisms ability to survive and reproduce, will be selected for and increase in frequency across the population. Similarly, traits that make it possible for organisms to learn behaviors would also be selected for if they are adaptive.
Hover over each image for a description.
|
Kinesis is a simple innate behavior wherein individuals move rapidly or slowly in response to a stimulus. If you have ever flipped a rock and watched pillbugs scurry...you have witnessed positive kinesis! In this week's lab, we will focus on the innate behavior of taxis: Positive taxis refers to movement toward a stimulus, where negative taxis refers to movement away from a stimulus.
There are many different types of taxis, but in this lab we will be studying the phototaxis and hydrotaxis of terrestrial isopods. Different types of Taxis
Terrestrial isopods are arthropods. Although we call them "pillbugs" and "sowbugs," they are actually crustaceans that occur in moist, dark areas, such as: forest floors, leaf and grass piles, and under dead logs where they eat detritus. Watch the short You Tube video and read over these 15 Natural History Traits of terrestrial isopods (pillbugs & sowbugs). Please note...these little guys cannot hurt you. They do not bite or sting and are quite gregarious & fun to work with.
|
Be sure you know the bold-face terms regarding animal behavior and the taxonomy of terrestrial isopods.
Know what ethology is, how it's related to ecological and evolutionary theory, and at least one good example.
Watch the short YouTube video on pillbugs. They share many traits with sowbugs.
Be sure you read over the 15 natural history traits of pillbugs/sowbugs.
|
what will we do in lab and how will we do it?
|
Lab 1 contains three exercises.
|
|
If you feel confident with this material, click the bridge icon below and navigate to Blackboard to take the LABridge for week 1. Be ready to be tested on this material before you go to the quiz. It is a timed assessment. * Please note, there is no Lab Notebook assignment for LABridge 1.
Click here to get to WKU's Blackboard to take your LABridge for this week.
Lab 1 Protocol
Following this lab you should be able to...
- Use the scientific method including hypothesis creation and data collection.
- Conduct an experiment using appropriate concepts like independent variables, dependent variables, and confounding variables.
- Examine different categories of behaviors and categorize them in proper ethological terms.
Overview. In today's lab you will get to know your lab mates and practice the scientific method by completing animal behavior experiments on terrestrial isopods.
- Exercise I. Group Contracts
- Exercise II. Animal Behavior Experiment
- Exercise III. Prepare for Data Analysis
exercise i. create a Group contract
Everyone has different opinions about group work, and depending on your past experiences and your own personality, group work may be exciting or dreaded. Maybe you consistently feel like you have to drag your group along to finish a project. Maybe you always feel a bit behind. Maybe you are just not terribly social and would prefer to work on your own. All these feelings are understandable, and group work can sometimes be problematic. However, scientific research is a team undertaking. None of us work in a bubble. To do and be our best, we rely on close relationships with colleagues for assistance, advice, shared knowledge, and shared resources. You will be working in groups throughout BIOL 123 and the best way to have a good group experience is to keep these important things in mind:
Procedure.
|
Roles for each member of your group. Click to enlarge.
Click here to download the contract.
|
Exercise Ii. Animal behavior experiment
Knowing the ecology of terrestrial isopods, we can make predictions about how they might perform in the lab when exposed to different environments (e.g., light vs. dark or wet vs. dry). However, we do not know which stimulus affects them the most. Do they prefer dark/dry places over wet/light places, or vice versa? Today, you will conduct an experiment to answer that question. Generating hypotheses can be a bit tricky if you struggle understanding the difference between your working hypothesis and your null hypothesis. Please review the descriptions below carefully before you begin.
- A null hypothesis (H0, or HNULL) represents the default position that there is nothing interesting going on in your data and your findings exist as result of chance and randomness (e.g., there is no difference between groups or there is no relationship between variables). We attempt to reject this idea and find support for our alternative hypothesis. Think: none, zero, zip, nada, null, nothing going, no difference, no preference, no relationship. The null is not "just the opposite" of your hypothesis.
- An alternative (or working) hypothesis (HA, H1, H2) states your claim or prediction. It is what you think might be happening. This hypothesis cannot be proven or accepted. If the H0 can be rejected based on our data, we may be able to show support for this idea.
Materials: You will be provided with pillbugs & sowbugs and should use your phones to take photos as you go and time your tests.
Procedure.
Notes: Our isopods are kept in a mixed community, housing both pillbugs and sowbugs. For this lab, you can use either or a mix of both species. You can use the paint brushes to direct them into your testing chambers. Tests 1 and 2 can be completed simultaneously if directed by your TA.
Notes: Our isopods are kept in a mixed community, housing both pillbugs and sowbugs. For this lab, you can use either or a mix of both species. You can use the paint brushes to direct them into your testing chambers. Tests 1 and 2 can be completed simultaneously if directed by your TA.
|
Download your Lab 1 Notebook Guide and Excel data sheet before you begin. Both are located in the sidebar.
Test 1:
|
Handle the isopods with care: they cannot hurt you, they are pretty resilient but be careful. Ethical treatment of animals is our responsibility.
Click to download.
Click to open your data sheet in Excel.
|
Exercise III. Preliminary AnalysisNext week, we will use the Chi-Square Goodness of Fit analysis to reveal which stimulus is preferred, if any, by your pill bugs. This statistic compares your distribution of data (your OBSERVED DATA) to that of a distribution you might predict from randomness, or you null hypothesis (the EXPECTED DATA). We need to do some preliminary analysis first.
Procedure.
How to save your lab notebook guide as as a pdf for submission
|
Expected vs. observed distributions.
Options for your "observed" data.
Enter your data here: Class Isopod Google Sheet.
|
Faculty Spotlight: Bruce Schulte
|
Bruce Schulte is our department's animal behaviorist, and he focuses on the communication and social behavior, mostly of herbivorous mammals, such as elephants, manatees, beavers, prairie dogs, and horses. Recently, he has collaborated on marine mammal research in Alaska. He uses a conservation behavior approach to reduce human-wildlife conflict by studying the behavioral ecology of these species. This research aims to increase our understanding of behavior to facilitate positive human-animal interactions. The Schulte lab has a major partnership project, Elephants and Sustainable Agriculture in Kenya (ESAK) that involves universities in Kenya, Wildlife Works, and citizen scientists through the EarthWatch Program. If you are interested in this type of research, please reach out to him today or checkout his course offerings TopNet. You can visit his lab webpage HERE and two recent publications are available below. Students who are interested in this work, please email @ [email protected].
|
2021. The chemical ecology of elephants: 21st century additions to our understanding and future outlooks.
2021. Musth and sexual selection in elephants: a review of signaling properties and potential fitness consequences.