Taxonomy (Biology)
In biology, taxonomy (from Ancient Greek τάξις (taxis), meaning 'arrangement', and -νομία (-nomia), meaning 'method') is the science of naming, defining (circumscribing) and classifying groups of biological organisms on the basis of shared characteristics. Organisms are grouped together into taxa (singular: taxon) and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a super-group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain, kingdom, phylum (division is sometimes used in botany in place of phylum), class, order, family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, as he developed a system known as Linnaean taxonomy for categorizing organisms and binomial nomenclature for naming organisms. With the advent of such fields of study as phylogenetics, cladistics, and systematics, the Linnaean system has progressed to a system of modern biological classification based on the evolutionary relationships between organisms, both living and extinct.
History
While some descriptions of taxonomic history attempt to date taxonomy to ancient civilizations, a truly scientific attempt to classify organisms did not occur until the 18th century. Earlier works were primarily descriptive and focused on plants that were useful in agriculture or medicine. There are a number of stages in this scientific thinking. Early taxonomy was based on arbitrary criteria, the so-called "artificial systems", including Linnaeus's system of sexual classification. Later came systems based on a more complete consideration of the characteristics of taxa, referred to as "natural systems", such as those of de Jussieu (1789), de Candolle (1813) and Bentham and Hooker (1862–1863). These were pre-evolutionary in thinking. The publication of Charles Darwin's On the Origin of Species (1859) led to new ways of thinking about classification based on evolutionary relationships. This was the concept of phyletic systems, from 1883 onwards. This approach was typified by those of Eichler (1883) and Engler (1886–1892). The advent of molecular genetics and statistical methodology allowed the creation of the modern era of "phylogenetic systems" based on cladistics, rather than morphology alone.
Reference: Wikipedia
The taxonomy of biologic organisms used on this website roughly follows the 7 Kingdoms of Life classification system proposed by Ruggiero, et al (2015), as opposed to a Domain or other classification system. The following quote is from the Ruggiero et al publication:
"We are proposing a two-superkingdom (Prokaryota and Eukaryota), seven-kingdom classification that is a practical extension of Cavalier-Smith’s six-kingdom schema; the latter has been used, for example, in the compendious checklist of marine biota of Chinese seas and in the first comprehensive national inventory of biodiversity for New Zealand. For each of these kingdoms we had to exercise our taxonomic judgment and reach a practical compromise among diverse opinions and usages and conflicting evidence about certain phylogenetic questions important for defining the boundaries between and ranks of major taxa, including kingdoms. Our schema includes: the prokaryotic kingdoms Archaea (Archaebacteria) and Bacteria (Eubacteria), and the eukaryotic kingdoms Protozoa, Chromista, Fungi, Plantae, and Animalia."
Reference: www.ncbi.nlm.nih.gov
