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Teaching Guide
Educator Notes
Growing Prairie
Indentifying Species
Follow Your Nose

TEACHER NOTE: If you don't have a color printer/copier, this can be done in black and white. Often an animal's color is variable and won't be included as a primary statement in a taxonomic key.


Part 1 - Grouping

  1. What was the first characteristic you used to divide the group? (answers will vary, although many will select to differentiate insects from spiders) Why did you pick this one?(spiders and insects are different groups identified by scientists)
  2. What characteristics did you use to continue dividing the groups up? Why? (Accept all reasonable answers. Use this as an opportunity to compare and contrast types of characteristics used to classify organisms)
  3. How many features did you need to separate all twenty organisms into their own distinct group? (19)
  4. What class do and flies belong to? (insects)
  5. What class do spiders and ticks below to? (arachnids)


  1. How many characteristics are used to differentiate organisms in each step of this key? (one characteristic)
  2. What are the two possible outcomes associated with each statement within a key? (name of the organism or a reference to another step)
  3. How many statement pairs are needed to distinguish between four species? (3 statement pairs)
  4. Did your key work for your partner? If not, what might have been done to improve it? (Answers will vary)


  1. How would you design a sampling technique to insure that you have a fair census of species in a 1,000 square meter field. Assume that the field has similar characteristics throughout. How many 1-square meter transects would you need to insure a representative sample that can be used to project realistic numbers? (answers will vary - but students will create the connection between increasing reliablity and increased samples)
  2. How would you locate these samples? (random selection)
  3. How might the number of samples affect the reliability of your survey? (more samples, less likely to be affected by "clumping" of species)
  4. What characteristics set the "tradeoff" between too few and too many samples? (many factors including uniform spread of organisms, relative density of organisms,. time, money, ease of sampling, terrain)


 Biology/Life Science:

 Science As Inquiry-Content Standard A
 Students should develop abilities necessary to do scientific inquiry,
 Students should develop an understanding about scientific inquiry
 Life Science -Content Standard C
 Students should develop an understanding of structure and function in living systems
 Students should develop an understanding of populations and ecosystems
 Students should develop an understanding of diversity and adaptations in organisms

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