The Murgon fossil site is a paleontological

Paleontology

Paleontology "old, ancient", ὄν, ὀντ- "being, creature", and λόγος "speech, thought") is the study of prehistoric life. It includes the study of fossils to determine organisms' evolution and interactions with each other and their environments...

 site of early Eocene

Eocene

The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 age in south-eastern Queensland

Queensland

Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

, Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. It lies near the town of Murgon, some 270 km north-west of Brisbane

Brisbane

Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...

. The Murgon site is important as the only site on the continent with a diverse range of vertebrate fossils dating from the early Tertiary Period (55 million years ago, only 10 million years after the extinction of the dinosaurs), making it a crucial period in mammal

Mammal

Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

 evolution. It is also important in demonstrating Australia's Gondwana

Gondwana

In paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...

n links with South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 in the form of similar fossils from the two continents.

Fossil fauna

Fossils from Murgon include the world's oldest songbird

Songbird

A songbird is a bird belonging to the suborder Passeri of the perching birds . Another name that is sometimes seen as scientific or vernacular name is Oscines, from Latin oscen, "a songbird"...

s, the oldest Australian marsupial

Marsupial

Marsupials are an infraclass of mammals, characterized by giving birth to relatively undeveloped young. Close to 70% of the 334 extant species occur in Australia, New Guinea, and nearby islands, with the remaining 100 found in the Americas, primarily in South America, but with thirteen in Central...

s, the only known fossils of leiopelmatid

Leiopelmatidae

Leiopelmatidae, or New Zealand and North American primitive frogs, is a family belonging to the suborder Archaeobatrachia. Their relatively primitive form indicates that they have an ancient lineage...

 frog

Frog

Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...

s, and the only Australian fossil salamanders. Evidence of the Gondwanan connection comes with the appearance of a madstoiid snake

Snake

Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...

 in the genus Alamitophis

Alamitophis

Alamitophis is a genus of fossil snake in the extinct family of Madtsoiidae. Its length is 80 cm and it fed on frogs, lizards, and small mammals. It is found in Australia and Argentina.-References:*...

, also found in Argentina, and of microbiotheriid marsupials

Microbiotheria

The Monito del Monte is the only extant member of its family and the only surviving member of an ancient order, the Microbiotheria. The oldest microbiothere currently recognised is Khasia cordillerensis, based on fossil teeth from Early Palaeocene deposits at Tiupampa, Bolivia...

, otherwise only known from South America. Other notable examples of the Murgon fauna are:

• Thylacotinga bartholomaii – a strange marsupial omnivore
  Omnivore
  Omnivores are species that eat both plants and animals as their primary food source...
  
  
• Tingamarra porterorum – a condylarth
  Condylarth
  Condylarthra is an order of extinct placental mammals known primarily from the Paleocene and Eocene epochs. Condylarths are among the most characteristic Paleocene mammals and they illustrate the evolutionary level of the Paleocene mammal fauna....
  
   and Australia's oldest placental
  Eutheria
  Eutheria is a group of mammals consisting of placental mammals plus all extinct mammals that are more closely related to living placentals than to living marsupials . They are distinguished from noneutherians by various features of the feet, ankles, jaws and teeth...
  
   land mammal
• Australonycteris clarkae
  Australonycteris clarkae
  Australonycteris is a monotypic extinct genus of microchiropteran bat with the single species Australonycteris clarkae. The species is known from fragmentary remains found at the Murgon fossil site, in south-eastern Queensland, dating to the early Eocene, 54.6 million years ago...
  
  – Australia’s earliest known bat
  Bat
  Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...
  
  species