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39-453: † Traversia Acanthisitta Xenicus † Dendroscansor Fossil genus, see text The New Zealand wrens are a family ( Acanthisittidae ) of tiny passerines endemic to New Zealand . They were represented by seven Holocene species in four or five genera , although only two species in two genera survive today. They are understood to form a distinct lineage within the passerines, but authorities differ on their assignment to

78-578: A genetic bottleneck caused by the marine transgression during the Oligocene , when most of New Zealand was under water. The earliest known fossil is Kuiornis indicator from the Early Miocene St Bathans fauna . Kuiornis is thought to be more closely related to Acanthisitta than to other Acanthisittids. The relationships between genera and species were formerly poorly understood. The extant genus Acanthisitta has one species,

117-557: A pre- Paleogene origin of passerines is highly disputed and tends to be rejected in more recent studies. As no evidence indicates passerines were flightless when they arrived on New Zealand (that apomorphy is extremely rare and unevenly distributed in Passeriformes), they are not required by present theories to have been distinct in the Mesozoic . As unequivocal Passeriformes are known from Australia some 55 million years ago,

156-542: A stick or stone". Historically, Lyall's wren was found only on Stephens Island . Prehistorically, it had been widespread throughout New Zealand before the land was settled by the Māori . Its bones can be found in caves and deposits left by laughing owls on both main islands. Its disappearance from the mainland was probably due to predation by the Polynesian rat or kiore ( Rattus exulans ), which had been introduced by

195-477: A synapomorphy is the marker for the most recent common ancestor of the monophyletic group consisting of a set of taxa in a cladogram. What counts as a synapomorphy for one clade may well be a primitive character or plesiomorphy at a less inclusive or nested clade. For example, the presence of mammary glands is a synapomorphy for mammals in relation to tetrapods but is a symplesiomorphy for mammals in relation to one another—rodents and primates, for example. So

234-484: A yellow stripe through the eye. Its underside was grey in females and brownish-yellow in males and its body feathers were edged with brown. Most distinctively, Lyall's wren was flightless , with a reduced keel on its breastbone and short rounded wings. It is the best known of the five flightless passerines (songbirds) known to science, all of which were inhabitants of islands and are now extinct . The others were three other New Zealand wrens (the long-billed wren and

273-526: Is a member of the family Acanthisittidae, or the New Zealand wrens – which are not wrens but a similar-looking lineage of passerines , originating in the Oligocene , and the sister group to all other songbirds . DNA analysis has confirmed that T. lyalli, the only member of its genus, is the oldest and most distinct lineage in the Acanthisittidae. Lyall's wren had olive-brown plumage with

312-406: Is either wrong or has been misinterpreted, starting with the account by Rothschild (1905) who claimed that a single cat had killed all of the birds. The research of Galbreath and Brown (2004) and Medway (2004) has uncovered much of the actual history of the bird during the short time that it was known to researchers. "there is very good reason to believe that the bird is no longer to be found on

351-557: The Ancient Greek words σύν ( sún ), meaning "with, together"; ἀπό ( apó ), meaning "away from"; and μορφή ( morphḗ ), meaning "shape, form". Lampreys and sharks share some features, like a nervous system, that are not synapomorphic because they are also shared by invertebrates . In contrast, the presence of jaws and paired appendages in both sharks and dogs, but not in lampreys or close invertebrate relatives, identifies these traits as synapomorphies. This supports

390-446: The Early Miocene St Bathans fauna New Zealand wrens are tiny birds; the rifleman is the smallest of New Zealand's birds. Their length ranges from 7 to 10 cm and their weight ranges from as little as 5–7 g for the rifleman, to an estimated 50 g for the extinct stout-legged wren . The New Zealand rock wren (and probably the bushwren) weighs between 14 and 22 g and the extinct long-billed wren weighed around 30 g. The plumage of

429-577: The Monterey pine . It also enters other human-modified habitat when it adjoins native forest. Like all New Zealand passerines, the New Zealand wrens are sedentary and are not thought to undertake any migrations . It is not known if the extinct species migrated, but it is considered highly unlikely, as three of the extinct species were flightless. The situation with the New Zealand rock wren is an ornithological mystery, as they are thought to live above

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468-690: The New Zealand rock wren , being restricted to alpine areas. Both the remaining species are poor fliers and four of the five extinct species are known or suspected to have been flightless. Along with the long-legged bunting from Tenerife , one of the Canary Islands , they are the only passerines known to have lost the ability to fly. Of the species for which the plumage is known, they are drab-coloured birds with brown-green plumage. They form monogamous pair bonds to raise their young, laying their eggs in small nests in trees or amongst rocks. They are diurnal and like all New Zealand passerines, are, for

507-559: The Stephens Island wren ( Traversia lyalli ) was a small, flightless passerine belonging to the family Acanthisittidae, the New Zealand wrens . Now extinct, it was once found throughout New Zealand, but when it came to the attention of scientists in 1894, its last refuge was Stephens Island in Cook Strait . Often claimed to be a species driven extinct by a single creature (a lighthouse keeper's cat named Tibbles),

546-473: The oscines or suboscines (the two suborders that between them make up the Passeriformes). More recent studies suggest that they form a third, most ancient, suborder Acanthisitti and have no living close relatives at all. They are called "wrens" because of similarities in appearance and behaviour to the true wrens (Troglodytidae) but are not members of that family. New Zealand wrens are mostly insectivorous foragers of New Zealand's forests, with one species,

585-475: The ovenbirds and antbirds . Sibley's 1970 study comparing egg-white proteins moved them to the oscines, but later studies, including the 1982 DNA-DNA hybridization study, suggested the family was a sister taxon to the suboscines and the oscines. This theory has proven most robust since then and the New Zealand wrens might be the survivors of a lineage of passerines that was isolated when New Zealand broke away from Gondwana 82–85 million years ago (Mya), though

624-494: The rifleman , and the other surviving genus, Xenicus , includes the New Zealand rock wren and the recently extinct bushwren. Some authorities have retained Lyall's wren in Xenicus as well, but it is often afforded its own monotypic genus, Traversia . The stout-legged wren (genus Pachyplichas ) was originally split into two species, but more recent research disputes this. The final genus was Dendroscansor , which had one species,

663-467: The Māori. The presence of a flightless bird on an island 3.2 km from the mainland, along with Hamilton's frog ( Leiopelma hamiltoni ), which can be killed by exposure to salt water, may seem puzzling, but Stephens Island was connected to the rest of New Zealand during the last glaciation when sea levels were lower. Much of what is commonly assumed to be established knowledge about this species' extinction

702-482: The New Zealand wrens is only known for the four species seen by European scientists. All these species have dull green and brown plumage and all except Lyall's wren have a prominent supercilium above the eye. The plumage of males and females were alike in Lyall's wren and the bushwren; the New Zealand rock wren shows slight sexual dimorphism in its plumage and differences between the plumage of riflemen are pronounced, with

741-443: The absence of mammals for many millions of years and the family was losing the ability to fly . Three species are thought to have lost the power of flight: the stout-legged wren, the long-billed wren and Lyall's wren. The skeletons of these species have massively reduced keels in the sternum and the flight feathers of Lyall's wren also indicate flightlessness. Contemporary accounts of the Lyall's wrens on Stephens Island describe

780-616: The acanthisittids' ancestors likely arrived in the Late Paleocene from Australia or the then- temperate Antarctic coasts. Plate tectonics indicate that the shortest distance between New Zealand and those two continents was roughly 1,500 km (930 mi) at that time. New Zealand's minimum distance from Australia is a bit more today – some 1,700 km (1,100 mi) – whereas it is now at least 2,500 km (1,600 mi) from Antarctica. The extant species are closely related and thought to be descendants of birds that survived

819-490: The alpine areas of the South Island and is considered vulnerable. The taxonomy of the New Zealand wrens has been a subject of considerable debate since their discovery, although they have long been known to be an unusual family. In the 1880s, Forbes assigned the New Zealand wrens to the suboscines related to the cotingas and the pittas (and gave the family the name Xenicidae). Later, they were thought to be closer to

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858-408: The birds' disappearance, was apparently not significant: in 1898, the island was described as heavily forested and there was little interference with habitat beyond the lighthouse and its associated buildings. Large-scale destruction of habitat started in late 1903, by which time T. lyalli was certainly extinct. About 16–18 specimens (excluding subfossil bones) are now known. They were collected by

897-531: The concept can be understood as well in terms of "a character newer than" ( autapomorphy ) and "a character older than" ( plesiomorphy ) the apomorphy: mammary glands are evolutionarily newer than vertebral column, so mammary glands are an autapomorphy if vertebral column is an apomorphy, but if mammary glands are the apomorphy being considered then vertebral column is a plesiomorphy. These phylogenetic terms are used to describe different patterns of ancestral and derived character or trait states as stated in

936-495: The cost of the state." Considering Buller's August 1895 note, it is probable that the species was exterminated by feral cats during the winter of 1895. Assuming the date of February 1894 for cat introduction was correct (there were certainly cats around in the winter months of that year), the winter of 1895 would see the second generation of cats born on the island reaching an age where the wren would have made ideal prey. Habitat destruction , sometimes given as an additional reason for

975-510: The hypothesis that dogs and sharks are more closely related to each other than to lampreys. The concept of synapomorphy depends on a given clade in the tree of life. Cladograms are diagrams that depict evolutionary relationships within groups of taxa. These illustrations are accurate predictive device in modern genetics. They are usually depicted in either tree or ladder form. Synapomorphies then create evidence for historical relationships and their associated hierarchical structure. Evolutionarily,

1014-547: The island, and, as it is not known to exist anywhere else, it has apparently become quite extinct. This is probably a record performance in the way of extermination." "And we certainly think that it would be as well if the Marine Department, in sending lighthouse keepers to isolated islands where interesting specimens of native birds are known or believed to exist, were to see that they are not allowed to take any cats with them, even if mouse-traps have to be furnished at

1053-626: The lighthouse keeper's cat, by the keepers themselves and by professional collectors. Apomorph Examples of apomorphy are the presence of erect gait , fur , the evolution of three middle ear bones , and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles , which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. The word synapomorphy —coined by German entomologist Willi Hennig —is derived from

1092-504: The long-billed wren. A mitochondrial DNA study in 2016 resolved much of the phylogeny, though the placement of Dendroscansor was unresolved due to lack of DNA testing due to the rarity of its remains. It was found that Xenicus was paraphyletic with respect to Pachyplichas , and that the stout legged wrens must have evolved from a gracile-legged ancestor, and the paper suggested placing the Pachyplichas species within Xenicus. It

1131-410: The male having bright green upperparts and the female being duller and browner. Both the New Zealand rock wren and the rifleman also show sexual dimorphism in size; unusually for passerines , the female is larger than the male. The female rifleman also exhibits other differences from the male, having a slightly more upturned bill than the male and a larger hind claw . The New Zealand wrens evolved in

1170-441: The most part, are sedentary . Like many New Zealand birds, New Zealand wrens suffered several extinctions after the arrival of humans in New Zealand. Of the seven Holocene species, only two survive today. The South Island stout-legged wren , North Island stout-legged wren , and long-billed wren became extinct after the arrival of the Māori and the Polynesian rat . They are known to science only from subfossil remains. At

1209-495: The rarest fossil finds in New Zealand. After the wave of extinctions and range contractions caused by the arrival of mammals in New Zealand, the New Zealand wrens have a much reduced range. The New Zealand rock wren is now restricted to the South Island and is declining in numbers. The range of the rifleman initially contracted with the felling of forests for agriculture, but it has also expanded its range of habitats by moving into plantations of introduced exotic pines , principally

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1248-572: The rifleman and bushwren included southern beech forest and podocarp-broadleaf forest, with the range of the bushwren also including coastal forest and scrub, particularly the Stewart Island subspecies. Currently, the New Zealand rock wren is confined to alpine and subalpine zones (900–2500 m altitude) on the South Island. It is possible that the species was once present in the North Island, although this has never been proven. Lyall's wren

1287-454: The same time, Lyall's wren became extinct on the main islands and survived only as a relict population on Stephens Island in the Cook Strait . Lyall's wren and the bushwren became extinct after the arrival of Europeans in 1895 and 1972 respectively. Of the two remaining species, the rifleman is still common in both the North and South Islands. The New Zealand rock wren is restricted to

1326-503: The snow line where obtaining food during the winter would be extremely difficult. Searches have found no evidence that they move altitudinally during the winter, but they are also absent from their normal territories. They may enter a state of torpor (like the hummingbirds of the Americas or a number of Australian passerines) during at least part of the winter, but this has not yet been proved. Lyall%27s wren Lyall's wren or

1365-584: The species as scurrying on the ground rather than flying. The New Zealand wrens are endemic and restricted to the main and offshore islands of New Zealand; they have not been found on any of the outer islands such as the Chatham Islands or the Kermadec Islands . Prior to the arrival of humans in New Zealand (about 1280 CE), they had a widespread distribution across both the North and South Islands and on Stewart Island/Rakiura . The range of

1404-462: The two species of stout-legged wren ) and the long-legged bunting from Tenerife , one of the Canary Islands , all of which were only recently discovered as fossils and became extinct in prehistoric times. Living Lyall's wrens were seen only twice. The lighthouse keeper described the 'rock wren', as he called it, as almost nocturnal, "running around the rocks like a mouse and so quick in its movements that he could not get near enough to hit it with

1443-510: The wren in fact fell victim to the island's numerous feral cats . The wren was described almost simultaneously by both Walter Rothschild and Walter Buller . It became extinct shortly thereafter. The bird's scientific name commemorates the assistant lighthouse keeper, David Lyall, who first brought the bird to the attention of science. It was described as a distinct genus, Traversia , in honour of naturalist and curio dealer Henry H. Travers , who procured many specimens from Lyall. Traversia

1482-554: Was also found that the split between Lyall's wren and other acanthisittids probably took place during the Oligocene, over 30 million years ago, so acanthisittids must have survived the Oligocene drowning . A cladogram is given below: † Lyall's wren , Traversia lyalli † Kuiornis indicator Rifleman , Acanthisitta chloris † Bushwren , Xenicus longipes New Zealand rockwren , Xenicus gilviventris † Pachyplichas – stout-legged wrens † Kuiornis indicator from

1521-490: Was once thought to have been restricted to the tiny Stephens Island in Cook Strait, but fossil evidence has shown the species was once widespread in both the North and South Islands. The stout-legged wren was similarly found on both islands, but fossils of the long-billed wren have only been found in the South Island. Fossils of the long-billed wren are far less common than those of the other species, in fact, its bones are

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