Teaching Principles of Experimental Design While Testing Optimal Foraging Theory

By Schwagmeyer, P. L.; Strickler, Stephanie A. | The American Biology Teacher, April 2011 | Go to article overview

Teaching Principles of Experimental Design While Testing Optimal Foraging Theory


Schwagmeyer, P. L., Strickler, Stephanie A., The American Biology Teacher


ABSTRACT

We describe a simple field study that we have found useful in introducing students to experimental design. Students manipulate the nutritive gain available from flowers to test the hypothesis that the foraging behavior of nectarivorous insects maximizes energy gain rate. They add sucrose solution to some flowers and water to others; additional flowers are left unmanipulated. Visit durations of foraging butterflies are then measured to test the prediction that individuals will forage longer at patches that offer higher energy gains. The project encourages students to consider how a study's design influences the results obtained, and helps to develop scientific reasoning skills.

Key Words: Adaptation; evolution; experimental design; optimal foraging; coevolution; animal behavior.

**********

The concept of adaptation via natural selection can be demonstrated beautifully to students by investigations of animal morphology or physiology, but studies of the behavior of organisms can be equally valuable. Animal behavior is especially amenable to experimental testing of hypotheses about adaptation and, thus, provides an opportunity for students to learn basic principles of experimental design.

Here, we describe a simple study that we have found useful in introducing students to fundamental properties of well-designed experiments in the context of testing hypotheses about adaptation. We use the experiment as the first of a series of projects conducted in an undergraduate animal behavior laboratory class. The course is for upper-division students, and in addition to collecting data, our students also find and read relevant primary literature, enter and analyze the data, and prepare a lab report in journal-style format. These components of student participation could easily be adjusted so that the study could be conducted in introductory biology labs or advanced placement high school biology courses. The project addresses the content category "Science as Inquiry" of the National Science Education Standards, as well as the "Life Sciences" (Behavior of Organisms, Biological Evolution) and "History and Nature of Science" (Nature of Scientific Knowledge) categories (National Research Council, 1996).

* Background

Virtually any behavior can be used for testing hypotheses about adaptation, but foraging is especially convenient because animals do it frequently and because the costs and benefits of various options that a foraging animal might have can be quantified. The cost/benefit approach to the study of foraging behavior, known as "optimal foraging theory," was devised in the late 1960s through mid-1970s, and it has served to explain multiple aspects of the food-acquisition behavior of animals (for a thorough review, see Stephens & Krebs, 1986; for a discussion of the role of optimality models in studies of adaptation, see Parker & Maynard Smith, 1990). One general use of the theory is the generation of predictions about which types of food animals should include in their diets versus which should be ignored. One might ask, "If I offer an animal a choice of prey items, will it prefer those that are of highest nutritive value?" or "If I offer prey items that are time-consuming to handle (e.g., nuts in shells) and also prey items that can be readily consumed (nuts without shells), will the animals prefer the prey with lower time costs?" An alternative application of the theory is to predict how long an individual should remain in a patch of food before leaving it to search elsewhere. If, for example, food patches are widely spaced (and so require a long time to get to), then one would generally predict that the amount of time spent foraging in each patch will be longer than if travel time between patches is very short. Or if environments vary from rich to poor, such that some habitats offer patches yielding high prey density and others have patches containing few prey, one would predict that animals in the rich environments should stay longer in each patch they visit. …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Note: primary sources have slightly different requirements for citation. Please see these guidelines for more information.

Cited article

Teaching Principles of Experimental Design While Testing Optimal Foraging Theory
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen
Items saved from this article
  • Highlights & Notes
  • Citations
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Search by... Author
    Show... All Results Primary Sources Peer-reviewed

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.