Dichotomous keys establish relationships among organisms based on shared characteristics.

Each dichotomous key involves making a choice between two choices using if ... then ... logic.

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• PART A - KEYING PETS

  p. 66 Dog, cat, parakeet, goldfish, rabbit: key:
  

  • fins
  • feathers
  • canines
  • muzzle

  Construct a key for your favorite pet. OPTIONAL: make up a different key.

• PART B - KEYING CLASSMATES

  Construct a key for 6-8 students.

• PART C - KEYING "FISH" p. 67

  Construct a key for fish; may be helpful to know fish anatomy.

  An example incorrect key.

  OPTIONAL: try constructing a key for MendAliens.

• PART D - KEYING AND BIODIVERSITY p. 68

  SKIP

• PART E - QUESTIONS p. 69

  (skip #3, #4 on P. 72)