History of botany scope of the subject as technology has opened up new techniques and areas of study. Modern molecular systematics, for example, entails the principles and techniques of taxonomy, molecular biology, computer science and more. Within botany there are a number of sub-disciplines that focus on particular plant groups, each with their own range of related studies (anatomy, morphology etc.). Included here are: phycology (algae), pteridology (ferns), bryology (mosses and liverworts) and palaeobotany (fossil plants) and their histories are treated elsewhere (see side bar). To this list can be added mycology, the study of fungi, which were once treated as plants, but
Medicinal plants According to Cancer Research UK, "there is currently no strong evidence from studies in people that herbal remedies can treat, prevent or cure cancer". A 2012 phylogenetic study built a family tree down to genus level using 20,000 species to compare the medicinal plants of three regions, Nepal, New Zealand and the South African Cape. It discovered that the species used traditionally to treat the same types of condition belonged to the same groups of plants in all three regions, giving a "strong phylogenetic signal". Since many plants that yield pharmaceutical drugs belong to just these groups, and the groups