Systematics and Phylogeny

Abstract

The aim of systematic research is to organize the huge diversity of organisms. This requires the recognition of species and their classification into systematic groups of higher rank (genera, families, etc.). Challenges in systematics include the description and naming of species and higher systematic groups and the provision of the means of identifying them in the form of a key. Since C. Darwin’s recognition of biological evolution (see Chap. 9), systematics has endeavored to reflect the natural relationships between organisms and groups of organisms when classifying individuals into species as well as classifying species into genera, genera into families, and so on. The only objective basis for classifying organisms is to use phylogenies that reflect natural relationships. In recent years, systematics has come much closer to its aim of classifying organisms according to relatedness because of the greater availability of DNA information for systematic analyses. The interpretation of this information in systematics, together with information from “traditional” character sources such as morphology, is tightly linked with the application of mathematical methods. Thus, the quality of systematic hypotheses can be tested statistically.