-- BIOCHEMICAL SYSTEMATICS 



and suggested that their proper tribal disposition should be in the 

 Anthemideae. Numerous similar cases could be cited. 



Of course, the term "fundamental" as applied to such charac- 

 ters is misleading. They are more appropriately called "key" charac- 

 ters in that they usually furnish an easily observed, mostly constant 

 feature by which to recognize the affinities of a given taxon. It often 

 takes the beginning student many years to appreciate this distinction, 

 and even today some otherwise well-informed professional taxono- 

 mists still think of certain single characters as "making" a given speci- 

 men and/or population a member of this or that species, tribe, family, 



and so forth. 



Cronquist (1957) has appropriately emphasized this pomt m 



stating: 



Every taxonomic character is potentially important, and no character 

 has an inherent, fixed importance; each character is only as important 

 as it proves to be in any particular instance in defining a group which 

 has been perceived on the basis of all of the available evidence. 



Stated otherwise, there is no inherent value in a selected 

 single character. As will be indicated in more detail elsewhere, this is 

 as true for chemical characters as it is for megamorphic features. 



Most systematic work of a biochemical nature has been 

 directed towards the evaluation and construction of phyletic schemes 

 for the higher taxonomic categories. For example, the detailed 

 serological work of Mez eventually resulted in the creation of 

 his now famous "Stammbaum" (Fig. 2-11). It seems apparent that 

 Mez' diagram was influenced by previous work which was based 

 essentially on exomorphic features. A critical discussion of the objec- 

 tives and hmitations of serology will be presented in Chapter 5 of the 



present text. 



With the development of rather rapid chromatographic tech- 

 niques which allow rapid detection of numerous chemical constituents 

 of organisms, it is now possible to make considerable new use of the 

 many phyletic diagrams which have been prepared by various mono- 

 graphers. Most chemotaxonomic studies of a correlative nature have 

 dealt with presumed phyletic relationships at the family level or 

 higher, reflecting, no doubt, the textbook famiharity of such systems 

 to many non-biologists. Interpretations of relationships at this level 

 are perhaps no better than the data on which they are based, and at 

 the present time these data are still quite hmited. 



With present knowledge and techniques, a more meaningful 

 application of biochemical data towards classificatory schemes may be 



