Taxonomy is the science of naming, describing and classifying organisms and includes all plants, animals and microorganisms of the world. Using morphological, behavioural, genetic and biochemical observations, taxonomists identify, describe and arrange species into classifications, including those that are new to science. Taxonomy identifies and enumerates the components of biological diversity providing basic knowledge underpinning management
and implementation of the Convention on Biological Diversity. Unfortunately, taxonomic knowledge is far from complete. In the past 250 years of research, taxonomists have named about 1.78 million species of animals, plants and micro-organisms, yet the total number of species is unknown and probably between 5 and 30 million. Click here for information on the biography and legacy of the
"father of taxonomy", Carl Linnaeus. What's in a Name?1 Different kinds of animals, fungi and plants and microorganisms are called different ‘species’. This reflects a real biological difference – a species is defined as a potentially interbreeding group of organisms that can produce viable offspring that themselves can interbreed. Thus animals of two different species, like a horse and a zebra, cannot interbreed, while animals of the
same species can. Taxonomists provide unique names for species, labels that can help us find out more about them, and enable us to be sure that we are all talking about the same thing. Of course, there are names for organisms in many languages, but it is important, for example, when discussing the hedgehog to know whether one is talking about the small spiny insectivore Erinaceus europaeus, other members of the same family, cacti of the genus Echinocerus, or the orange fungus Hydnum
repandum, all of which have the same ‘common’ name in English. For this reason the Latin ‘scientific’ name, is given as a unique universal identifier. How to Name a Species: the Taxonomic Process1 Taxonomists begin by sorting specimens to separate sets they believe represent species. Once the specimens are sorted the next job is to see whether or not they already have names. This may involve working through identification guides, reading descriptions written
perhaps 200 years ago, and borrowing named specimens from museums or herbaria to compare with the sample. Such comparison may involve external characters, need to dissect internal structures, or even molecular analysis of the DNA. If there is no match the specimens may represent a new species, not previously given a name. The taxonomist then has to write a description, including ways in which the new species can be distinguished from others, and make up a name for it, in a Latin format. The name
and the description must then be properly published so that other taxonomists can see what has been done, and be able to identify the species themselves. From finding the specimens to the name appearing in print can take several years. 1. Text taken from: Secretariat of Convention on Biological Diversity. 2007. Guide to the Global Taxonomy Initatiative, CBD Technical Series # 27
NOTIFICATIONSIn the 18th century, Carl Linnaeus published a system for classifying living things, which has been developed into the modern classification system. People have always given names to things that they see, including plants and animals, but Linnaeus was the first scientist to develop a hierarchal naming structure that conveyed information both about what the species was (its name) and also its closest relatives. The ability of the Linnean system to convey complex relationships to scientists throughout the world is why it has been so widely adopted. Despite existing for hundreds of years, the science of classification — taxonomy — is far from dead. Classification of many species, old and new, continues to be hotly disputed as scientists find new information or interpret facts in new ways. Arguments are fierce and species do change names, but only after a wealth of information has been gathered to support such a big step. One of the new reasons why species are being re-evaluated is because of DNA analysis. Basic genetic analysis information can change our ideas of how closely two species are related and so their classification can change, but how does the whole system work? Nature of scienceImproved technologies have altered our understanding of the world. In astronomy, the invention of the telescope enabled astronomers to observe outer space and see what they hadn’t been able to see before, and biologists use the microscope to observe the unseen world. Now, DNA technology has allowed scientists to re-examine the relationships between organisms to refine the classification system. KingdomWhen Linnaeus first described his system, he named only two kingdoms – animals and plants. Today, scientists think there are at least five kingdoms – animals, plants, fungi, protists (very simple organisms) and monera (bacteria). Some scientists now support the idea of a sixth kingdom – viruses – but this is being contested and argued around the world. PhylumBelow the kingdom is the phylum (plural phyla). Within the animal kingdom, major phyla include chordata (animals with a backbone), arthropoda (includes insects) and mollusca (molluscs such as snails). Phyla have also been developed and reorganised since the original work by Linnaeus – as scientists discover more species, more categories and subcategories are put in place. ClassEach phylum is then divided into classes. Classes within the chordata phylum include mammalia (mammals), reptilia (reptiles) and osteichthyes (fish), among others. OrderThe class will then be subdivided into an order. Within the class mammalia, examples of an order include cetacea (including whales and dolphins), carnivora (carnivores), primates (monkeys, apes and humans) and chiroptera (bats). FamilyFrom the order, the organism will be classified into a family. Within the order of primates, families include hominidae (great apes and humans), cercopithecidae (old world monkeys such as baboons) and hylobatidae (gibbons and lesser apes). Genus and speciesFinally, the classification will come to the genus (plural genera) and species. These are the names that are most commonly used to describe an organism. One outstanding feature of the Linnean classification system is that two names are generally sufficient to differentiate from one organism to the next. An example within the primate family is the genus Homo for all human species (for example, Homo sapiens) or Pongo for the genus of orangutan (for example, Pongo abelii for the Sumatran orangutan or Pongo pygmaeus for the Bornean orangutan). Constant evolutionWhile this system of classification has existed for over 300 years, it is constantly evolving. Classification in the 1700s was based entirely on the morphological characteristics (what something looks like) of the organism. Those that looked most alike were put closest together in each category. This can be depicted as a tree, with the diverging branches showing how different the species become as you move out from the kingdoms (trunk). Now, a radical shift in the grouping of organisms is occurring with the development of DNA technologies. Sequencing of the genetic code of an organism reveals a great deal of information about its similarity with and relationship to other organisms, and this classification often goes against the traditional morphological classification. Scientists are debating which species are most closely related and why. Currently in New Zealand, there are projects to sequence kiwi and tuatara DNA that may revolutionise the way we think about these species and their closest living relatives. However, DNA technology is still expensive and time-consuming, so the first step in any classification continues to rely on a comparison of morphological features, similar to the process that Linnaeus undertook in the 1700s. Activity ideaYour students can learn more about how the Linnaean classification system works with this activity, Insect mihi. Students write a formal introduction for an insect species of their choice, including information about the insect’s relationship to other animals and also the land. Find out moreClassification is not a field that stays still and this means scientists and taxonomists sometimes have to reassess classifications. Learn more in Leon Perrie's thought provoking blog, Why do scientific names change? Would you like to take a short survey?This survey will open in a new tab and you can fill it out after your visit to the site. Why is the standardized taxonomic system of classifying organisms important?Why is taxonomy so important? Well, it helps us categorize organisms so we can more easily communicate biological information. Taxonomy uses hierarchical classification as a way to help scientists understand and organize the diversity of life on our planet.
Which of the following best explains why a standardized classification system is important to the scientific community?Which of the following best explains why a standardized classification system is important to the scientific community? It allows different kinds of organisms to be easily identified based on their characteristics.
What is the importance of a classification system nomenclature and identification?Explanation: It is important because the classification of organisms show the relationship between the organism and its contemporaries. It also shows evolutionary relationships between the organism and its ancestors. Organisms grouped in similar ranks show similarities amongst its members.
Which best explains the need for a system of biological classification?Which best explains the need for a system of biological classification? Scientists can gather more meaningful information by studying relationships among various organisms.
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Which of the following best explains the importance of having a standardized taxonomic classification system when determining the relatedness of organisms?
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