Plant Taxonomy (BIOL308)  -  Stephen G. Saupe, Ph.D.; Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321; ssaupe@csbsju.edu; http://www.employees.csbsju.edu/ssaupe/

Dichotomous Key Writing - Checklist

Does the key......... 

q       start each couplet with a noun?
q       avoid unnecessary words?
q       avoid negatives?
q       avoid trichotomies?
q       use "absent" vs. "not present"?
q       quantify when possible?
q       have couplets that refer to the same feature?
q       have couplets that include all of the potential variations in the feature?
q       have mutually exclusive statements in each couplet?
q       remember that keys are for identification and not designed to show evolutionary relationships (i.e., keys are "artificial") thus, don't worry about maintaining "natural" groupings?
q       avoid vague terms?
q       rely on features from the same season?
q       avoid the use of taxonomic names (i.e., plant a gymnosperm)?
q       use obvious features and avoid obscure or highly technical ones?
q       use fixed features, avoid highly variable ones?
q       start with the most distinctive features?
q       have n -1 couplets?

Last updated:  08/20/2007 / � Copyright by SG Saupe