Classification and Keying p. 33
Dichotomous keys establish relationships among organisms based on shared traits,
and grouping them into clades.
Each key involves making a choice between two possibilities: does the organism possess the key (trait) or not?
Note the shared trait should be something the organism has, not something it does not have.
- Keys should be unique to a clade.
- Keys should not be repeated.
Example for five geometrical figrures:
PROCEDURE p. 34
PART A - KEYING CLASSMATES
Construct a key for 6-8 students.
PART B - KEYING "FISH" p. 35
Construct a key for fish;
may be helpful to know fish anatomy.
An example incorrect key.
PART C - KEYING OF SHELLS
PART D - KEYING AND BIODIVERSITY p. 36
PART E - QUESTIONS