The Science of Plant Classification

GOALS of TAXONOMYIDENTIFY all members of the plant kingdom

NAME all plants

ARRANGE plants into a HIERARCHY that indicates their TRUE relationship to another

HISTORY of PLANT CLASSIFICATION

ARTIFICIAL CLASSIFICATION

NATURAL CLASSIFICATION

PHYLOGENTIC CLASSIFICATION

ARTIFICIAL CLASSIFICATIONForm and Use

Ancient Greeks

THEOPHRASTUS (371-287 BCE)

DIOSCORIDES (40-90 CE)

ARTIFICIAL CLASSIFICATIONMiddle Ages

Monocots vs. dicotsVascular vs. non-vascularDescriptive names

Herbalistsherbariums

ARTIFICIAL CLASSIFICATION LINNAEUS (1707-1778

CE)Binomial NomenclatureSystem based on the

flower and sexual parts

NATURAL CLASSIFICATIONSystem based on

MORPHOLOGY of plant parts (shape or form)

French Botanists

Used today, although not considered “true relationships”, but closer

PHYLOGENETIC CLASSIFICATIONBased on TRUE

GENETIC relationships of plants

CHARLES DARWIN (1809-1882 CE)Origin of Species

(1859) Theory of Evolution

explained Natural Selection as a

means of adaptation

TAXONOMY TODAYMade up of NATURAL and PHYLOGENETIC

classification

Governed by International Code of Botanical Nomenclature (ICBN)Rules for naming plantsRevised as new evidence becomes available

Dynamic – ever changing system Based on observations and systematic

gathering of evidence