Alcoota
Encyclopedia
The Alcoota Fossil Beds are an important paleontological site located on Alcoota Station in Central Australia
, 200km north-east of Alice Springs. It is notable for the occurrence of well-preserved, rare, Tertiary
vertebrate fossils, which provide evidence of the evolution of the Northern Territory’s fauna and climate. The Alcoota Fossil Beds are also significant as a research and teaching site for palaeontology students.
The Alcoota deposit is a series of intermittently interconnected lakes within a large basin. Evidence suggests that the concentration of fossils is due to a phenomenon called ‘waterhole-tethering’: During dry periods, animals concentrated in the intermediate area of the continually shrinking spring-fed lake, resulting in the death of many animals. The Alcoota and Bullock Creek
fossil faunas provide evidence that aridification was in progress in northern Australia during the mid Miocene
geological time period.
commenced an annual excavation program. In 1988 a permanent field station was erected on site and the valuable Alcoota Beds were fenced in order to provide them with some protection.
The Alcoota fauna is about 8 million years old and has a rich concentration of vertebrate fossils. This makes it especially interesting as it lies between the older faunas of Kutjamarpu (Southern Australia) and Bullock Creek (Northern Territory) and the younger deposits of Riversleigh
(Queensland) and Beaumaris
(Victoria). Because of its intermediate age, remote ancestors of the well-studied Australian megafauna
as well as of some existing forms can be recognized.
s, bird
s and crocodile
s, including the greatest variety of species of Diprotodontidae
that has ever been described.
The species found include one of the largest birds that ever lived, Stirton's Thunderbird Dromornis stirtoni, the giant birds Ilbandornis lawsoni and Ilbandornis woodburnei, the wolf-sized Powerful Thylacine (Thylacinus potens
) and the large leopard-sized Alcoota Marsupial Lion (Wakaleo alcootaensis
). Also found at Alcoota are fossils of herds of the wombat-like diprotodontoids Kolopsis torus and Plaisiodon centralis, the trunked Palorchestes painei, Pyramio alcootense as well as other kangaroo
s, crocodiles, bandicoot
s, possum
s and small birds.
Central Australia
Central Australia/Alice Springs Region is one of the five regions in the Northern Territory. The term Central Australia is used to describe an area centred on Alice Springs in Australia. It is sometimes referred to as Centralia; likewise the people of the area are sometimes called Centralians...
, 200km north-east of Alice Springs. It is notable for the occurrence of well-preserved, rare, Tertiary
Tertiary
The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...
vertebrate fossils, which provide evidence of the evolution of the Northern Territory’s fauna and climate. The Alcoota Fossil Beds are also significant as a research and teaching site for palaeontology students.
The Alcoota deposit is a series of intermittently interconnected lakes within a large basin. Evidence suggests that the concentration of fossils is due to a phenomenon called ‘waterhole-tethering’: During dry periods, animals concentrated in the intermediate area of the continually shrinking spring-fed lake, resulting in the death of many animals. The Alcoota and Bullock Creek
Bullock Creek
The Bullock Creek Fossil site is one of three known vertebrate fossil sites in the Australia's Northern Territory, along with the Alcoota Fossil Beds on Alcoota Station and the Kangaroo Well site on Deep Well Station. It is located about 550km south-southeast of Darwin, on Camfield Station...
fossil faunas provide evidence that aridification was in progress in northern Australia during the mid Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
geological time period.
History
The Alcoota Fossil Beds are one of only three known vertebrate fossil sites in the Northern Territory, along with Bullock Creek and the Kangaroo Well site. Although locals had known about the existence of fossils at Alcoota for a long time, it was not until 1962 that the first serious studies were conducted. Further excavations were conducted sporadically until 1984, when the Museum and Art Gallery of the Northern TerritoryMuseum and Art Gallery of the Northern Territory
The Museum and Art Gallery of the Northern Territory is the main museum in the Northern Territory. The museum is located in the inner Darwin suburb of Fannie Bay...
commenced an annual excavation program. In 1988 a permanent field station was erected on site and the valuable Alcoota Beds were fenced in order to provide them with some protection.
The Alcoota fauna is about 8 million years old and has a rich concentration of vertebrate fossils. This makes it especially interesting as it lies between the older faunas of Kutjamarpu (Southern Australia) and Bullock Creek (Northern Territory) and the younger deposits of Riversleigh
Riversleigh
Riversleigh, in North West Queensland, is Australia's most famous fossil site. The 100 km² area has fossil remains of ancient mammals, birds and reptiles of Oligocene and Miocene age...
(Queensland) and Beaumaris
Beaumaris, Victoria
Beaumaris is a suburb in Melbourne, Victoria, Australia, 20 km south-east from Melbourne's central business district. Its Local Government Area is the City of Bayside. At the 2006 Census, Beaumaris had a population of 12,441....
(Victoria). Because of its intermediate age, remote ancestors of the well-studied Australian megafauna
Australian megafauna
Australian megafauna are a number of large animal species in Australia, often defined as species with body mass estimates of greater than 30 kilograms, or equal to or greater than 30% greater body mass than their closest living relatives...
as well as of some existing forms can be recognized.
Fossils
The fossil deposit consists of a series of bone-bearing lenses on a single horizon. The individual lenses are about one metre across and extend for 170m. Bones and teeth are so abundant and often tightly packed that it can be difficult to excavate one fossil without breaking the one below it. The fossils indicate the existence of a complex community of marsupialMarsupial
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, bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s and crocodile
Crocodile
A crocodile is any species belonging to the family Crocodylidae . The term can also be used more loosely to include all extant members of the order Crocodilia: i.e...
s, including the greatest variety of species of Diprotodontidae
Diprotodontidae
Diprotodontidae is an extinct family of large, actively mobile marsupial, endemic to what would be Australia, during the Oligocene through Pleistocene periods from 28.4 mya—11,000 years ago, existing for approximately .-References:...
that has ever been described.
The species found include one of the largest birds that ever lived, Stirton's Thunderbird Dromornis stirtoni, the giant birds Ilbandornis lawsoni and Ilbandornis woodburnei, the wolf-sized Powerful Thylacine (Thylacinus potens
Thylacinus potens
Thylacinus potens was the largest species of the family Thylacinidae, known from a single poorly preserved fossil discovered by Michael O. Woodburne in 1967 in a Late Miocene locality near Alice Springs, Northern Territory. It preceded the modern thylacine by 4–6 million years, and was 5% bigger,...
) and the large leopard-sized Alcoota Marsupial Lion (Wakaleo alcootaensis
Wakaleo
Wakaleo , was a genus of medium-sized thylacoleonids that lived in Australia in the early to late Miocene. It was approximately 2.5 ft long, or the size of a dog...
). Also found at Alcoota are fossils of herds of the wombat-like diprotodontoids Kolopsis torus and Plaisiodon centralis, the trunked Palorchestes painei, Pyramio alcootense as well as other kangaroo
Kangaroo
A kangaroo is a marsupial from the family Macropodidae . In common use the term is used to describe the largest species from this family, especially those of the genus Macropus, Red Kangaroo, Antilopine Kangaroo, Eastern Grey Kangaroo and Western Grey Kangaroo. Kangaroos are endemic to the country...
s, crocodiles, bandicoot
Bandicoot
Bandicoots are a group of about 20 species of small to medium-sized, terrestrial marsupial omnivores in the order Peramelemorphia.- Etymology :...
s, possum
Possum
A possum is any of about 70 small to medium-sized arboreal marsupial species native to Australia, New Guinea, and Sulawesi .Possums are quadrupedal diprotodont marsupials with long tails...
s and small birds.
External links
- http://www.lostkingdoms.com/snapshots/miocene_late_alcoota.htm Australia's Lost Kingdoms - Late Miocene period - About Alcoota
- http://www.nt.gov.au/nreta/heritage/managing/facts/pdf/alcoota.pdf Alcoota Fossil Beds