This document discusses the classification of organisms and the evolution of taxonomy. It describes Aristotle's early classification system and how Linnaeus improved on it by developing a hierarchical system of classification from kingdom down to species. The Linnaean system is more accurate than Aristotle's because it is based on evolutionary relationships and morphology. Binomial nomenclature assigns every species a two-part scientific name. Modern taxonomy uses multiple lines of evidence, including fossils, morphology, embryology, and molecular comparisons to construct phylogenetic trees showing evolutionary relationships.