Taxonomy

• Taxonomy is a branch of biology that solely focuses on identifying and classifying organisms. In taxonomy, scientists place organisms into groups with similarities. The order of groupings, from largest to smallest, is kingdom, phylum, class, order, family, genus and species. The largest grouping is called "kingdom," and includes large numbers of organisms. For instance, the group "animalia" includes all animals and currently includes over a million species. The smallest grouping is "species" and refers to one specific type of organism. There are several variations on the taxonomic system that have more or fewer kingdoms, but most current biologists use the five-kingdom system that Robert Whittaker created in 1969.
  
  

Evolution

• One of the primary reasons for taxonomy is to study evolution. Organisms with common traits -- for instance, horses and zebras -- evolved from common ancestors. By studying organisms that are alive today and grouping them by similar traits, scientists can speculate on these common ancestors, determining what they were like and how they evolved. This in turn helps scientists to study the relationships between similar organisms today and to determine what evolutionary directions organisms might take next. It also helps with understanding species diversity and how species evolve to fit different ecological niches.
  
  

Conservation

• Along with categorizing species, taxonomy describes and identifies them. This has many practical uses, including protecting the environment. If a species is described correctly, then it is possible to accurately identify and monitor instances of that species in an ecosystem. This helps a scientist determine what areas a species inhabits and how large an area it inhabits. This is useful for both keeping track of species that are becoming endangered or extinct and keeping track of invasive species that may be causing harm to an ecosystem.
  
  

Nomenclature

• Arguably the most important reason for taxonomy and categorizing species is so that scientists have a common language for communication. In the taxonomic system, every identified species has two names, called binomial nomenclature. In binomial nomenclature, the first name of a species is its genus and the second is a word that describes the organism. In this way, looking at the name of an organism tells a scientist both what other organisms are related and the specific organism that is being described. Because every species, even similar species, has its own name, it is possible for scientists to communicate information about organisms, even across languages, since the scientific name is the same in every language. If a species has been categorized correctly, there is no confusion over which species is under discussion.