Short answers, pulled from the story.
Taxonomy in biology is the scientific study of naming, defining, and classifying groups of biological organisms based on shared characteristics. Modern approaches prioritize common ancestry and evolutionary relationships. Organisms are grouped into taxa and assigned a taxonomic rank, building a hierarchy.
Carl Linnaeus, the Swedish botanist who lived from 1707 to 1778, is regarded as the founder of the current system of taxonomy. He developed a ranked system known as Linnaean taxonomy and implemented a standardized binomial naming system through works including Systema Naturae in 1735 and Species Plantarum in 1753.
The principal ranks in modern use are domain, kingdom, phylum, class, order, family, genus, and species. Division is sometimes used in botany in place of phylum. Groups of a given rank can be aggregated into a more inclusive group of higher rank.
The term taxonomy was introduced in 1813 by de Candolle in his work Théorie élémentaire de la botanique. John Lindley provided an early definition of systematics in 1830, though he wrote of systematic botany rather than using the term systematics.
Alpha taxonomy refers to finding, describing, and naming taxa, particularly species. William Bertram Turrill introduced the term in papers published in 1935 and 1937. Ernst Mayr in 1968 defined beta taxonomy as the classification of ranks higher than species.
Charles Darwin's On the Origin of Species, published in 1859, led to classifications based on evolutionary relationships and the principle of common descent. Tree of life representations became popular, and the cladistic method later emerged from the 1960s, arranging taxa so that named groups are monophyletic.
The Catalogue of Life listed 1.64 million species for all kingdoms, claiming coverage of more than three-quarters of the estimated species known to modern science. It is one of several database-driven treatments alongside the Encyclopedia of Life and the Global Biodiversity Information Facility.