BIOL 1001 Chapter 19: chapter 19
Document Summary
Systematic biology, classification and taxonomy help us organize and understand information about the biological world. The science of systematics- the study of the diversity of life and its evolutionary relationships- has two major goals: one is to reconstruct the phylogeny or evolutionary history of a group of organisms, presented as phylogenetic trees. These are formal hypotheses identifying likely evolutionary relationships among species: the second goal is taxonomy, the identification and naming of species and their placement in a classification. A classification is an arrangement of organisms into hierarchical groups that reflect their relatedness. Classifications should mirror phylogenetic history and the adaptive radiation (evolutionary history) of the group of organisms in question. Linnaeus described and named thousands of species on the basis of their similarities and differences. The organisms included within any category of the taxonomic hierarchy compromise a taxon. Systematists use guidelines to select characters for study. They seek characters that are independent markers of underlying genetic similarity and difference.