History of plant systematics

The history of plant systematics—the biological classification of plants—stretches from the work of ancient Greek to modern evolutionary biologists. As a field of science, plant systematics came into being only slowly, early plant lore usually being treated as part of the study of medicine. Later, classification and description was driven by natural history and natural theology. Until the advent of the theory of evolution, nearly all classification was based on the scala naturae. The professionalization of botany in the 18th and 19th century marked a shift toward more holistic classification methods, eventually based on evolutionary relationships. The peripatetic philosopher Theophrastus (372–287 BC), as a student of Aristotle in Ancient Greece, wrote Historia Plantarum, the earliest surviving treatise on plants, where he listed the names of over 500 plant species. He did not articulate a formal classification scheme, but relied on the common groupings of folk taxonomy combined with growth form: tree shrub; undershrub; or herb. The De Materia Medica of Dioscorides was an important early compendium of plant descriptions (over five hundred), classifying plants chiefly by their medicinal effects. The Byzantine emperor Constantine VII sent a copy of Dioscorides' pharmacopeia to the Umayyad Caliph Abd al-Rahman III who ruled Córdoba in the 9th century, and also sent a monk named Nicolas to translate the book into Arabic. It was in use from its publication in the 1st century until the 16th century, making it one of the major herbals throughout the Middle Ages. The taxonomy criteria of medieval texts is different from what is used today. Plants with similar external appearance were usually grouped under the same species name, though in modern taxonomy they are considered different. Abū l-Khayr's botanical work is the most complete Andalusi botanical text known to modern scholars. It is noted for its detailed descriptions of plant morphology and phenology.