The following points highlight the thirty-six important Swingle’s principles for plant classification. Swingle’s Principle # 1. Plant relationships are up and down genetic lines and these must constitute the framework of phylogenetic taxonomy. Swingle’s Principle # 2. Some evolutionary processes are progressive while others are regressive. Swingle’s Principle # 3. Evolution does not necessarily involve all organs of the plant [...]
The following points highlight the fifteen important Thorne’s principles (1958) of plant classification. Thorne’s Principle # 1. Existing species have descended with change from pre-existing species and are therefore, the products of evolutionary forces. Thorne’s Principle # 2. Ancestral conditions and trends of specialisation are often recognisable in the organs, tissues and cells of living and fossil angiosperms. Thorne’s Principle [...]
In this article we will discuss about the contribution of various botanists towards plant classification. 1. Sexual (or Artificial) System of Linnaeus: Carolus Linnaeus (1707-1778), a Swedish naturalist published a sexual system of classification in Hortus Uplandicus (1730) and elaborated it in his Genera Plantarum (1737). The latter work is of importance in modern taxonomy as a source of description [...]