The study of plants has played a significant, if sometimes undervalued, role in history. Plants have been important in science, medicine and economic affairs since Antiquity. The herbal tradition dominated investigations until the Renaissance after which it ran alongside developing areas of expertise in classification and physiology. In the eighteenth century, plant sciences became significant in geographical exploration and in general culture. Nineteenth-century botanists used plants for investigating cell theory and early genetics as well as in evolutionary biology.