ABSTRACT
Systematics aims at developing classifications based on different criteria and, often a distinct methodology is employed for the analysis of data. Data handling to establish relationships between the organisms often makes use of one of the two methods: phenetic methods and phylogenetic methods, often providing different types of classification. Distinction is sometimes also made between phylogenetic and evolutionary classification schemes. Phylogenetic methods aim at developing a classification based on an analysis of phylogenetic data, and developing a diagram termed cladogram or phylogenetic tree, or more recently, simply tree, which depicts the genealogical descent of taxa. Biologists practicing this methodology are known as cladists, and the field of study as cladistics. The term, however, is slowly being replaced by phylogenetic systematics. The phylogenetic concepts present a huge diversity of variation, unfortunately often contradictory, leading to different interpretations of similar results. A brief understanding of these is, therefore, necessary before attempting to explore this complex field. Before the development of modern methods of cladistics, the numerical methods were largely used for drawing phylogenetic inferences from the data analysis. The modern Phylogenetic methods, however, integrate the concepts and practices
of numerical taxonomy with cladistic methods. It is, however, essential to understand the concepts of each, and the final integration in phylogeny reconstruction.
