The system of natural classification created by Linnaeus (1707-1778), exposed in the Systema naturae and universally adopted, is currently being challenged by the so-called Phylo-code. This transformation of taxonomy deeply modifies not only the system of classification, but also, if not above all, the concept of classification itself. Such a radical mutation is not unprecedented, however. Not to speak of Linnaeus' system, a true revolution happened well before, in antiquity. In the 1st cent. AD, indeed, Dioscorides renounced to classify plants according to the four types system created by Theophrastus (ca. 371-ca 287 BC), but adopted a new order, based on a first evolutionist concept of nature. On the basis of a full analysis of ancient treatises in their original language, the paper will present this radical mutation. To this end, it will first briefly present Theophrastus' system and then reconstruct the new one adopted by Dioscorides. It will identify its theoretical fundament, and follow its diffusion and reception in ancient science, focusing then on its persistence and adaptations over time, until the dawn of Pre-Modern Botany.

Key words: Dioscorides, epistemology, history, Linnaeus, phylo-code, plant classification