How to Make a Taxonomy Key

Decide how specific the key needs to be, depending on what is being identified. For example, if you are categorizing types of money, the chart will be fairly simple to make. If you are making a key for the various types of land mammals, the key will need to have many statements, each carefully planned and plotted.

Choose a form to determine how you want the taxonomic key to look. The format can be a spider key, where there are two lines branching out from each category, or it can be more in an outline format. If you choose an outline format, each question will have two answers: Answer A and Answer B. Each of the different answers will then direct you to another question. For example, if you choose "Answer A" you may be told to go to question 2. If you choose "Answer B," you might be told to go to question 3. Whichever format you select, just be certain it is well-organized and easy for the reader to follow.

Develop the questions to ask on the taxonomy key. To do this, you will need to focus on the similarities and the differences between the item you are trying to classify. For instance, if you were trying to create a taxonomy chart to classify money, the first difference to identify would be that some money is made of paper and some money is made of metal. Once you identify this difference, the first question on your taxonomy key could say "Is the item made of paper or metal?" If the user of the taxonomy key chose "paper" (answer choice A) they could be directed to question 2, which might then ask about what color the paper was. If the user of the taxonomy key chose "metal" (answer choice B) they could be directed to question 3, which might then ask about the type of metal or the size of the coin. By continuing to ask questions, you can narrow down the focus of each paired statement until the object is identified.

Check your work. Double the taxonomic key by taking the objects and working through the key to ensure the correct answers and that all statements make sense.