Correlation, Evaluation, and Presentation of Taxonomic Data

Abstract

Both classification and identification depend upon a certain degree of character correlation and also upon discontinuity in the correlation patterns. Plant identification usually requires the use of only a few of a plant’s more obvious morphological characteristics, and only one or two characteristics are usually considered at any one time as the plant is worked through the key. In plant classification, on the other hand, it is necessary to consider and to evaluate all the pertinent information more or less simultaneously. Up to a point, an experienced taxonomist who has studied his material thoroughly can do this. Experience with a group of plants tends to develop a subconscious “feel” for the entities involved and for their interrelationships, and often this highly subjective evaluation is the basis for taxonomic opinion. So far all plants (and animals) have been classified by this method. This is not to say that the method is perfect or even that it is the best that can be devised. Indeed, as more aspects of biology are brought to bear on problems of relationship it is necessary to devise new ways of presenting larger numbers of variation patterns in such a way that they can be evaluated simultaneously and more objectively. Such methods not only help the taxonomist in his evaluations, but are of tremendous value in showing others how the taxonomist arrived at his conclusions.