How to Make a Dichotomous Key Using Word

by Timothy Banas

Taxonomists--scientists who classify things into groups--create and use dichotomous keys to help others identify the objects and organisms they are studying. Biologists often create dichotomous keys for the purpose of tree or insect identification, for instance. Typically, the first step of a dichotomous key looks something like this: 1a. The insect has wings................................................go to step 2 1b. The insect has no wings...........................................go to step 5 Reader uses the characteristics presented in each step in a choose-your-own-adventure kind of way to eventually end up at the proper name of the object or organism that he's looking at. Microsoft Word is a useful tool for creating a dichotomous key in the format indicated above, and it is very easy to use.

Create a new Microsoft Word document and call it "Dichotomous Key."

Type the title and any introduction that is necessary to describe your dichotomous key at the top of the page and then go to the first line where you will be typing the steps of your dichotomous key.

Click "Format" in the menu bar at the top of the window and choose "Tabs" from the options presented. You might have to expand the format menu to see the tabs option by clicking on the down arrow at the bottom of the menu.

In the "Tab stop position" box, type the number of inches from the left of the pages that you want each line in your key to end. Use the ruler at the top of the word document to help; a good default number of inches is 6. Press "Enter" and the number will drop into the box below.

Click the number you just typed in the box below the "Tab stop position" box to highlight it.

Under the "Alignment" options, choose "Right."

Under the "Leader" options, choose "........ ."

Click "Set" and then "OK" and the dialog box should disappear.

Type the first step in your dichotomous key and then hit "Tab." A leader consisting of a series of dots will appear and your cursor will be moved to the right side of the page, where you can now type your "Go to step X" instruction.

Press "Enter" to go to the next line and continue adding steps to your key.

Things You Will Need

  • Microsoft Word

About the Author

Timothy Banas has a master's degree in biophysics and was a high school science teacher in Chicago for seven years. He has since been working as a trading systems analyst, standardized test item developer, and freelance writer. As a freelancer, he has written articles on everything from personal finances to computer technology.

Photo Credits

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