Create Your Own Dichotomous Key

Question

In this project, you will be creating a dichotomous key. Dichotomous keys are tools used by scientists to identify unknown organisms. To create your key, follow the steps outlined below. All completed projects will be worth 50 points and will be graded according to the attached rubric. Good Luck, Have Fun, and Be Creative!
1. Choose a group of non-scientific items that interest you. Example: Candy, Shoes,
Aliens, etc.
2. Select 10 different species from this group. Locate and print out or create
pictures of each one. These will be included in your project.
3. Decide upon a way to divide the items into two groups. Think of identifying
characteristics such as shape, size, position, color, texture, etc. One characteristic must be defined and used to decide which items are placed in which group. For example: a group of big cats could be divided into those with long tails and those with short tails. The groups created must be opposites of each other.
4. Record what factor was used to make the division and note which members of the
original group belonged to each resulting group.
5. After two groups (A and B) have been created, divide the first group (A) into two more groups based again on one criterion (C and D). For example, if group A were the short tailed cats, group C might be short tailed cats with a plain colored coat. Group D would then be short tailed cats with a patterned coat.
6. Do the same with Group B.
7. Continue to divide the groups until each item is by itself. Keep careful records of
the groups that were created and the dividing criteria.
8. Looking at your records and the divisions you made, create a dichotomous key that
would lead someone else to make the same distinctions you did. Begin your key by recalling the first factor you used to divide into two groups. Again using the big cat example: The first group was created depending on tail length. So, the first question in the key should be: Does the cat have a short tail? If so, go to step 2. The second question should be the other choice: Does the cat have a long tail? If so, go to step ??? (You may need to wait until you have worked through several steps of the key to assign the second destination.
9. You can use the attached paper as a framework to fill in your key or you can type
your own.
10. When your key is complete, ask someone else to use it to classify and identify the
items. Does your key lead others to the same identifications you made? If not, you may need to make some changes.
Important Requirements!!!
✓ Include a page with the 10 illustrations you selected. They should be identified
ONLY by the letters A-J. DO NOT INCLUDE THE NAMES ON THIS PAGE!!!
✓ Provide an answer key as the last page of
Helpful Hints:
your project.
1. While you are constructing your key, you must be as specific as possible so that
the user does not become confused. If the two choices are not precise, a user can easily choose the wrong one, and may get the wrong classification or have to start over.
2. Have several people use the key to see if their answers match with yours. If
they do not, analyze the key with them and compare your choices to see where they got confused. You may need to re-word your choices.
3. All keys should have one fewer steps than items. So your key should have 2
steps with two choices for each one.
Grading Rubric: Your project will be graded according to the following rubric:
10 pts. Ten colourful, clear, accurate, and easy to understand illustrations were
provided.
5 pts. A completed answer key was provided.
10 pts. All steps of Dichotomous Key were complete.
10 pts. The Dichotomous Key followed the proper structure (identifying
characteristics were used to create steps of paired opposites).
10 pts. The Dichotomous Key was accurately worded. I successfully used it to
identify all 10 items.
5 pts. The Dichotomous Key included proper spelling, punctuation and grammar.
All included documents were neat, legible, and easy to identify.
/50 Total points
Grading Rubric: Your project will be graded according to the following rubric:
10 pts. Ten colorful, clear, accurate, and easy to understand illustrations
were provided.
5 pts. A completed answer key was provided.
10 pts. All steps of the Dichotomous Key were complete.
10 pts. The Dichotomous Key followed the proper structure (identifying
characteristics were used to create steps of paired opposites).
10 pts. The Dichotomous Key was accurately worded. I successfully used it
to identify all 10 items.
5 pts. The Dichotomous Key included proper spelling, punctuation and grammar. All included documents were neat, legible, and easy to identify.
/50 Total points

Answer 1

Project: Dichotomous Key for Types of Candy

Step 1: Choose Group

The group I've chosen is Candy.

Step 2: Select 10 Different Species

1. Chocolate Bar
2. Gummy Bear
3. Lollipop
4. Hard Candy
5. Marshmallow
6. Taffy
7. Licorice
8. Sour Candy
9. Jellybean
10. Candy Cane

Step 3: Divide Items into Two Groups

First Division Criterion: Texture

• Group A (Soft Texture): Gummy Bear, Marshmallow, Taffy
• Group B (Hard Texture): Chocolate Bar, Lollipop, Hard Candy, Licorice, Sour Candy, Jellybean, Candy Cane

Step 4: Group Records

• Group A (Soft Texture):

  • Gummy Bear
  • Marshmallow
  • Taffy

• Group B (Hard Texture):

  • Chocolate Bar
  • Lollipop
  • Hard Candy
  • Licorice
  • Sour Candy
  • Jellybean
  • Candy Cane

Step 5: Divide Group A

Second Division Criterion for Group A: Flavor

• Group C (Fruity Flavor): Gummy Bear, Marshmallow

• Group D (Creamy Flavor): Taffy

• Group C (Fruity Flavor):

  • Gummy Bear
  • Marshmallow

• Group D (Creamy Flavor):

  • Taffy

Step 6: Divide Group B

Second Division Criterion for Group B: Type

• Group E (Chocolate or Creamy): Chocolate Bar, Licorice

• Group F (Non-Chocolate): Lollipop, Hard Candy, Sour Candy, Jellybean, Candy Cane

• Group E (Chocolate or Creamy):

  • Chocolate Bar
  • Licorice

• Group F (Non-Chocolate):

  • Lollipop
  • Hard Candy
  • Sour Candy
  • Jellybean
  • Candy Cane

Step 7: Further Divide Each Group

• Group C (Fruity Flavor):

  • Gummy Bear
  • Marshmallow
  • (Fruity Flavor: Gummy Bear; Non-Fruity Flavor: Marshmallow)

• Group E (Chocolate or Creamy):

  • Chocolate Bar
  • Licorice
  • (Chocolate: Chocolate Bar; Non-Chocolate: Licorice)

• Group F (Non-Chocolate):

  • Lollipop
  • Hard Candy
  • Sour Candy
  • Jellybean
  • Candy Cane
  • (Sucker: Lollipop; Non-Sucker: Hard Candy, Sour Candy, Jellybean, Candy Cane)

Final Steps of Group F:

• Hard Candy:
  • Hard Candy
  • (Soft: Sour Candy; Other: Jellybean; Hard: Candy Cane)

Summary of Deductions

• Group C (Fruity):

  • Gummy Bear (A)
  • Marshmallow (B)

• Group E (Chocolate):

  • Chocolate Bar (E)
  • Licorice (F)

• Group F (Non-Chocolate):

  • Lollipop (G)
  • Hard Candy (H)
  • Sour Candy (I)
  • Jellybean (J)
  • Candy Cane (K)

Create the Dichotomous Key

1. Does the candy have a soft texture?

   • Yes → Go to 2 (Group A)
   • No → Go to 5 (Group B)

2. Does the candy have a fruity flavor?

   • Yes → Gummy Bear (A)
   • No → Marshmallow (B)

3. Is the candy chocolate or creamy?

   • Yes → Go to 6 (Group E)
   • No → Go to 7 (Group F)

4. Is the candy a bar?

   • Yes → Chocolate Bar (C)
   • No → Licorice (D)

5. Is the candy round and on a stick?

   • Yes → Lollipop (E)
   • No → Go to 8 (Group F)

6. Is the candy hard?

   • Yes → Hard Candy (F)
   • No → Go to 9

7. Is the candy sour?

   • Yes → Sour Candy (G)
   • No → Go to 10

8. Is the candy jelly-shaped?

   • Yes → Jellybean (H)
   • No → Candy Cane (I)

Illustrations

On a separate page, include illustrations labeled A-K corresponding to each type of candy without any written names.

Answer Key

1. A: Gummy Bear
2. B: Marshmallow
3. C: Chocolate Bar
4. D: Licorice
5. E: Lollipop
6. F: Hard Candy
7. G: Sour Candy
8. H: Jellybean
9. I: Candy Cane

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Important Notes:

• Ensure illustrations are colorful, clear, and easy to recognize.
• Double-check that the text is free from spelling and grammatical errors.
• Test the key with others for effectiveness. Adjust as necessary based on feedback.