Australornis
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''Australornis'' (Latin: "southern bird") is a
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
seabird Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...
discovered in
New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
. It lived in the
Paleocene epoch The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''palaió ...
, 60.5 to 61.6 million years ago (Ma). The
type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...
name originates from ''australis'', Latin for "southern", and ''ornis'', the Greek word for "bird", and ''lovei'' commemorates Leigh Love, an amateur paleontologist who discovered it. ''Australornis'' is one of the oldest flying seabirds. It is also the first non- sphenisciform (penguins and allies) bird fossil discovered from New Zealand for that age. The fossil originates from an era just after the
Cretaceous–Paleogene extinction event The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary extinction) was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago. With the ...
66 million years ago. The features of the bird indicate that it does not belong to any of the extant bird families, but to a precursor group or
clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...
which is extinct; hence it is a find of global significance with regard to the
evolution of birds Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation t ...
. Though the fossil evidence is incomplete to substantiate phylogeny, ''Australornis'' contributes to the emerging view that the diversification of Neoaves had already begun in the earliest Paleogene. ''Australornis'' is also of zoogeographical significance, as New Zealand was much closer to
Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...
during the
Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...
and
Early Paleocene The Danian is the oldest age or lowest stage of the Paleocene Epoch or Series, of the Paleogene Period or System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretaceo ...
and it would have originated over deep waters of a warm sea off the coast of
Zealandia Zealandia (pronounced ), also known as (Māori) or Tasmantis, is an almost entirely submerged mass of continental crust that subsided after breaking away from Gondwanaland 83–79 million years ago.Gurnis, M., Hall, C.E., and Lavier, L.L., ...
, now a nearly submerged continent or microcontinent that sank after breaking away from Australia between 60 and 85 million years ago and on which New Zealand rests.


Discovery

The fossil was discovered in 2009 by Leigh Love in the
Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), E ...
Waipara Greensand The Waipara Greensand is a geological rock unit found in Canterbury, New Zealand. It dates from just after the Cretaceous–Paleogene extinction event, the Thanetian and Selandian, around 61–62 million years ago in the early Palaeocene. It is ...
of north
Canterbury Canterbury (, ) is a City status in the United Kingdom, cathedral city and UNESCO World Heritage Site, situated in the heart of the City of Canterbury local government district of Kent, England. It lies on the River Stour, Kent, River Stour. ...
on the
South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...
of
New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
. The fossil was deposited in the
Canterbury Museum, Christchurch The Canterbury Museum is a museum located in the central city of Christchurch, New Zealand, in the city's Cultural Precinct. The museum was established in 1867 with Julius von Haast – whose collection formed its core – as its first director ...
, where it lay in museum shelves for a number of years, as earthquakes severely affected the working of the Museum staff. The fossil was described in 2014 by Dr Gerald Mayr, from the Senckenberg Research Institute and Natural History Museum in
Frankfurt-am-Main Frankfurt, officially Frankfurt am Main (; Hessian dialects, Hessian: , "Franks, Frank ford (crossing), ford on the Main (river), Main"), is the most populous city in the States of Germany, German state of Hesse. Its 791,000 inhabitants as o ...
, and Dr Paul Scofield of the Canterbury Museum, who published their findings in the ''Journal of the Royal Society of New Zealand''.


Description

''Australornis'' grew roughly to about long, and has been likened to a pied shag in size. It is thought to have weighed between . ''Australornis'' is known from the following remains: * right
coracoid A coracoid (from Greek κόραξ, ''koraks'', raven) is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is prese ...
(extremitas omalis) * right
scapula The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on eithe ...
(caudal portion) * right
humerus The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
(less the distal end) * right
ulna The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of t ...
(proximal end only) * fragments of the shaft of a
radius In classical geometry, a radius ( : radii) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', meaning ray but also the ...
* left os carpi radiale The wing and pectoral girdle bones of this avian fossil have been found to be quite distinct. While there is not enough fossil material from ''Australornis'' to enable a phylogenetic study linking it with extant bird groups, it has been found to share certain derived characteristics with a number of modern bird taxonomic groups, namely
Procellariiformes Procellariiformes is an order of seabirds that comprises four families: the albatrosses, the petrels and shearwaters, and two families of storm petrels. Formerly called Tubinares and still called tubenoses in English, procellariiforms are of ...
,
Gaviiformes Gaviiformes is an order of aquatic birds containing the loons or divers and their closest extinct relatives. Modern gaviiformes are found in many parts of North America and northern Eurasia (Europe, Asia and debatably Africa), though prehistoric ...
and
Rallidae The rails, or Rallidae, are a large cosmopolitan family of small- to medium-sized, ground-living birds. The family exhibits considerable diversity and includes the crakes, coots, and gallinules. Many species are associated with wetlands, althoug ...
. ''Australornis lovei'' has similarities to two fossil avians from Antarctica - the similarly-sized ''
Vegavis iaai ''Vegavis'' is a genus of extinct bird that lived during the Late Cretaceous (Maastrichtian stage) of Antarctica, some 68 to 66 mya. Among modern birds, most studies show that ''Vegavis'' is most closely related to ducks and geese (Anatidae), b ...
'' (Noriega & Tambussi 1995) from the late Cretaceous (68 - 66 Ma) of
Vega Island Vega Island is a small island to the northwest of James Ross Island, on the Antarctic Peninsula. It is separated from James Ross Island by Herbert Sound. The island was named by Otto Nordenskjold, leader of the Swedish Antarctic Expedition (190 ...
, Antarctica and '' Polarornis gregorii'' (Chatterjee 2002) from the
Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...
López de Bertodano Formation The Lopez de Bertodano Formation is a geological Formation (geology), formation in the James Ross Island, James Ross archipelago of the Antarctic Peninsula. The strata date from the end of the Late Cretaceous (upper-lower Maastrichtian stage) to t ...
of
Seymour Island Seymour Island or Marambio Island, is an island in the chain of 16 major islands around the tip of the Graham Land on the Antarctic Peninsula. Graham Land is the closest part of Antarctica to South America. It lies within the section of the isla ...
of Antarctica. Though ''Australornis'' was found near the fossils of '' Waimanu manneringi'', the oldest fossil penguin, found in the same level of strata in Waipara and regarded to be of the same age, it lacks any morphological resemblances to penguins. In 2017 a phylogenetic study Agnolín and colleagues have found ''Australornis'' to be stem-
anseriform Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which inc ...
s along with '' Polarornis'', ''
Neogaeornis ''Neogaeornis'' is a controversial prehistoric genus of diving bird. The single known species, ''Neogaeornis wetzeli'', was described from fossils found in the Campanian to Maastrichtian Quiriquina Formation of Chile. It lived about 70-67 million ...
'' and ''
Vegavis ''Vegavis'' is a genus of extinct bird that lived during the Late Cretaceous (Maastrichtian stage) of Antarctica, some 68 to 66 mya. Among modern birds, most studies show that ''Vegavis'' is most closely related to ducks and geese (Anatidae), b ...
'' in the family
Vegaviidae Vegaviidae is an extinct family of ornithurines, often regarded as stem-anseriforms, which existed during the Late Cretaceous and possibly the Paleocene. Fossils attributed to the family have been found in Canada, Chile, New Zealand, and Antarct ...
.


References

{{Taxonbar, from=Q16735964 A Paleocene birds Fossil taxa described in 2014 Extinct birds of New Zealand