Taxonomy is the science of naming, describing and classifying organisms. It underpins everything from picking out different plants at the nursery to being able to rapidly identify new invasive species. Like most fields of study, taxonomy is continuously evolving based on new scientific discoveries (new species being described), as well as techniques such as genetic sequencing and advanced imaging which can change the way researchers understand existing species.


Organising species with the ALA’s ‘taxonomic backbone’


Taxonomy is the fundamental basis for how data in the Atlas of Living Australia (ALA) are organised. To do this, we’ve developed a way to arrange species in the ALA – we call it our ‘taxonomic backbone’. Learn more about how the ALA manages taxonomy, even as taxonomy changes over time.

How organisms are organised

All living things are at least distantly related to one another, some more closely than others. To group like organisms together, taxonomists use levels known as ‘ranks’ to classify how a species or group is related to other living things. The combination of names in this hierarchy allows scientists to build a picture of how all species are interrelated. The broadest taxonomic rank is ‘kingdom’. Most of the species we would recognise in daily life would belong to kingdoms Animalia, Plantae, or Fungi, but there are others, such as Archaea and Protists. Moving down a few ranks, we have ‘class’. Many of the animals that are familiar to most people are grouped in one of these classes, such as Mammalia (mammals), Reptilia (reptiles), Aves (birds), and Amphibia (amphibians).


For example, the koala (Phascolarctos cinereus), belongs to:

animalia (kingdom) – chordata (phylum) – mammalia (class) – diprotodontia (order) – phascolarctidae (family) – Phascolarctos (genus) – cinereus (species)


a koala, and the various taxonomic ranks it belongs to

Left: Koala (Phascolarctos cinereus); right: the taxonomic ranks (groupings) Koala belongs to.



Species names

For most organisms, ‘species’ is the most specific level of the taxonomic tree. All species have a common name and a scientific name. Day to day, most of us refer to species using what’s known as their ‘common’ or ‘vernacular’ name. For example, the koala (Phascolarctos cinereus), or golden wattle (Acacia pycnantha). For most of our daily needs, this is sufficient and convenient.

The ALA displays Indigenous names for species, where they are available and we have consent to do so. Some species can have multiple Indigenous names, even from a single language group. For example, the Emu (Dromaius novaehollandie) has many Indigenous names shown in the ALA.

Several Indigenous language names for species in the ALA



For scientific purposes, using common names alone lacks the curatorial controls and precision that that scientists need in their work. For example, a common name for a species may act as an umbrella term which actually encapsulates multiple species (e.g. salt bush, gum tree, kangaroo). In addition, common names can be similar and easily confused, e.g. bush stone-curlew and beach stone-curlew (Burhinus grallarius & Esacus magnirostris). Finally, a single species may have multiple commons names, e.g. Eucalyptus camaldulensis (Called river red gum, and Murray red gum as well as flooded gum and many other local names).


To overcome this, taxonomists use a species, or ‘scientific’ name to refer to a living organism.  All living things known to science have a scientific name. These names are comprised of a generic name (the first part) and a specific name – the ‘specific epiphet’ (the second part). For example, the koala’s scientific name is Phascolarctos cinereus. Phascolarctos is the generic name and cinerus is the specific epiphet. Scientific names are always italicised, with the generic name (Phascolarctos) is capitalised and the specific epithet (cinereus) always in lower case. Normally, the scientific name is included in brackets after the common name.


common name (koala), generic name (phascolarctos) and specific epiphet (cinereus) for the koala


Scientific names are derived from Latin, as the science of naming species began in the 18th century when Latin was the dominant language used in all science. The scientific name will often describe a species, the circumstances of its naming or be named after someone. For example, what most people know as river red gum has the scientific name Eucalyptus camaldulensis. In the cause of the river red gum, camaldulensis refers to the French private estate garden (L'Hortus Camaldulensis di Napoli) where the type specimen was grown from seed from Australia.



two images of the river red gum, showing the whole tree and a close up of the leaves

River Red Gum (Eucalyptus camaldulensis) tree (left) and close up detail of leaves (right).



Taxonomists apply a scientific name by publishing a scientific description of the new species based on a particular series of specmens. These specimens are known as ‘type specimens’ and are stored in permanent biological collections such as museums and herbaria. New species can also be described with other forms of evidence, such as detailed photographs and sound recordings. Genetic characteristics are also playing an increasingly important role in species differentiation and taxonomic naming.


As we learn more about the relationships between species, species names can change. For example, a species may need to be moved into a different genus from the one in which it was originally described, or a widely-distributed species may be found to actually be several unique species. This is why some species can have additional names – ‘synonyms’ – to allow users to see the links between existing and previous names.


Subspecies, forms, varieties and strains

Some species can also have sub-units known by names such as subspecies (abbreviated as subsp.), forms (f.), varieties (var) or strains. For example: the eastern subspecies of the regent parrot is known as (Polytelis anthopeplus) sub species (monarchoides Schodde), 1993. In this example, monarchoides identifies the eastern form of the regent parrot. The specific (epiphet anthopeplus) tells us we are talking about the regent parrot and Polytelis is the group of parrots to which the regent parrot belongs, which includes two other species, the princess parrot (Polytelis alexandriae) and the superb parrot (Polytelis swainsonii).


three birds within genus Polytelis

Three species within genus Polytelis – left: the eastern regent parrot (Polytelis anthopeplus subsp. monarchoides); middle: princess parrot (Polytelis alexandriae); right: superb parrot (Polytelis swainsonii).



Author names

Scientific names are correctly referred to including the author name at the end. For the eastern regent parrot (Polytelis anthopeplus sub species monarchoides) Schodde, 1993 – it tells us that Schodde described the eastern regent parrot subspecies in 1993.



Informal names

Did you know? Around two thirds of the species in Australia are currently unknown to western science!


Taxonomy is an exciting science that classifies and names species all the time. Around two thirds of the species in Australia are currently unknown to western science. Like all branches of science, taxonomists have theories that they test when describing new species and they use an informal name or phrase name system when they suspect there is a new species. For example Eucalyptus aff. camaldulensis is a species that has affinities with river red gum but might be a new species. A more certain identification might be described as Eucalyptus Bulahdelah (RGB 20455 Bert) which represents a (fictional) probable new specimens identified by a specific specimen at a specific herbarium from a specific area.



Taxonomy is the science of naming, describing and classifying organisms. Scientists use a scientific name derived from Latin to name species – this is to ensure clarity and precision. Species may also have one or more ‘common’ or ‘vernacular’ names, as well as names in Indigenous languages. Taxonomists organise species into different groups, the levels of these different groups are known as ‘ranks’. These ranks get broader as we move up the tree of life, and include genus, family, class, and kingdom, though there are several others.