Cladistics illustrates the ever-developing evolutionary relations between life forms, while the Linnaean system classifies organisms according to fixed physical traits. Cladistics organizes all life within a frame of evolutionary theory, while the Linnaean system reaches back to an Aristotelian concept of scientific names.
Cladistics is a method developed to pair the evolutionary model with the practical need for classification of organisms. Cladistics shows branches of evolution and allows users to see how closely related one species is to another species at any point of their evolutionary histories. Cladistics organizes life in accordance to the history of development rather than to the similarity of one life form with another at any one time. Cladistics is not intended for use outside work involving the theory of evolution.
Carl Linnaeus developed his system in an attempt to give every distinct form of life a universal name and a place within a structure of all life according to physical similarities. This structure designates a species, genus, family, order, class and kingdom for each organism. Linnaeus relied on a previous model of classification offered by Aristotle, though Linnaeus changed and enlarged Aristotle's model. The Linnaean system groups species with physical similarities together regardless of the different ways those traits were developed in each species.