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Koala (Phascolarctos cinereus) Fact Sheet: Taxonomy & History

Taxonomic History & Nomenclature

Below taxonomy according to Integrated Taxonomic Information System and Colin Groves 2006 (ITIS 2006)

Diprotodontia: Largest order of marsupials with 11 families
Family: Koalas are the only member of Phascolarctidae
Subspecies (Houlden et al.1999) (Sherwin et al. 2000)

  • Three subspecies were historically described but reflect clinal morphological variation, not evoluntionarily distinct units based on genetic evidence (Queensland to Australia)
  • For convenience, established boundaries of the subspecies are state boundaries
  • DNA studies do not show enough differentiation to support the use of subspecies

Common Name: (Dixon et al. 2006)

  • Koala
    • Erroneously reported as stemming from an Aboriginal word meaning "no drink" or "doesn't drink"
    • Progressively Anglicized from the Aborinine Dharuk tribal word gulawañ, gula for short
      • 1798 - settlers near Sydney describe small, sloth-like creatures; assigning the name "cullawine"
      • Coola and koolah quickly emerged as shortened versions; described as a fairly accurate representation of the Aboriginal gula (pronounced both as gula or kula)
      • Scribal error likely introduced koala into the vernacular; koala and koola used through much of the 19th century
  • Also known as monkey bear, native bear, tree-bear, and koala bear (Dixon et al. 2006)

Scientific Name:

  • Phascolarctos
    • phaskolos from Greek for 'leather bag or pouch'
    • arktos from Greek for 'bear'
  • cinereus
    • Latin for "ash-colored"

Evolutionary History

Marsupial and placental mammals diverged around 190 million years ago (Meredith et al 2011)
Koala-like marsuials and wombat-like marsupials diverged about 40 to 30 million years ago (Late Eocene to Early Oligocene) (Kirsch et al. 1997) (Beck 2008):

  • Koalas became arboreal; wombats remained on the ground
  • Koalas have no close living relatives

Koala family (Phascolarctidae) dates at least to 15 million years ago (Middle Miocene) (Sherwin et al. 2000)(Black 1999)

  • Early koalas believed to have been tree-climbing rainforest dwellers (Archer et al. 1991)
  • Diversity of koala fossils is high: 18 named species, 5 genera (Louys et al 2009)

By 11 to 5 million years ago (Late Miocene), koalas began to adapt to drier Eucalyptusdominated open woodlands (Archer et al. 1991)

  • Skull adaptations included strengthened jaws for chewing tough Eucalyptus leaves (Louys et al 2009)

In Pleistocene times Phascolarctos stirton was twice as large as today's koala (Long et al. 2002)
Koalas are the only surviving member of the Phascolarctidae family
Koalas have little in common tree sloths (which are placental mammals), despite frequent comparisons

  • A slow moving lifestyle is the extent of their similarity

Cultural History

Dreamtime (folk) tales of the Arrente tribe in Central Australia often refer to koalas (Reed 2000) (Jackson 2007):

  • One legend describes The Rainbow and the Koala
    • A skilled hunter needed to find his lost boomerang
    • He stretched a killed koala to make an arched bridge to a faraway land
    • People walked over this bridge when they first entered Australia
    • The bridge became multicolored, the first rainbow
    • A boy who was one of the first to arrive was turned into a koala
    • Others who came across the bridge were the founders of the various Australian Aboriginal tribes, each with their own animal totem
  • A second legend is but one of many describing why koalas have no tails:
    • A long time ago koalas had a tail that helped them hang in trees
    • Once during a time of drought, a lyre bird noticed that a koala in a tree seemed to always have water there to drink
    • The lyre bird became jealous and set the tree on fire
    • The tree split into many fragments, releasing its water
    • All the animals gathered to drink torrents of water
    • Sadly, the lyre bird's feathers were singed brown on the edges and the koala tail was consumed in the fire

Koalas figure prominantly in Australian Aboriginal art (Bingham 2005)

Popular culture references

  • Documentary appearances
    • Yindi the Last Koala - 1996
      • An hour long documentary on the Koala, Yindi. We follow the young Koala as he is reunited with his mother after a car crash. Viewers get to witness the special ways humans help Koalas.
    • Cracking the Koala Code - 2012, PBS
      • This hour long episode from season 33 of Nature follows individual koalas from a small social group on an Australian island.
    • Koala Hospital Documentary - 2013
      • An Australian hospital for Koala's is documented for over 3 years. The hospital has been caring for sick and injured Koala's for over 40 years.
  • Other appearances
    • Koalas Saved - National Geographic
      • 2 minute video of Environmentalists in Australia protecting their country's iconic species.


Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Diprotodontia (11 families, 110 species; includes kangaroos, wombats, pygmy possums, gliders and others)

Suborder: Vombatiformes (wombats and koalas)

Family: Phascolarctidae (koalas)

Genus: Phascolarctos

Species: Phascolarctos cinereus — koala


Describer: Goldfuss (1817) as Lipurus cinereus

Source: Jackson and Groves (2015)

Page Citations

Archer et al. (1991)
Beck (2008)
Bingham (2005)
Black (1999)
Dixon et al. (2006)
Houlden et al. (1999)
Jackson (2007)
Kirsch et al. (1997)
Lee & Martin (1988)
Louys et al. (2009)
Meredith et al. (2011)
Reed (2000)
Sherwin et al. (2000)
Takami et al. (1998)

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