Moas are eleven species in six genera of now extinct flightless birds endemic to New Zealand. Prior to the settlement of the New Zealand Islands by the Polynesians around 1280, the Moa population is estimated to have fluctuated around 58,000 individuals. Moas have been the dominant herbivores in New Zealand’s forest, shrub and subalpine ecosystems for millennia. Moa disappeared around 1300 — 1440 ± 30 years, mainly due to over-hunting by the newly arrived Maori people.
Origin of the species and description
Moas belong to the order Dinornithiformes, which belongs to the group of ratites. Genetic studies have shown that its closest relative — a South American tinamou that can fly. Although it was previously believed that kiwi, emu and cassowary were most closely related to moa.
Video: Moa bird
Dozens of moa species were described in the late 19th and early 20th centuries, but many varieties were based on partial skeletons and duplicated each other. Currently, 11 species are officially recognized, although recent studies of DNA recovered from bones in museum collections suggest that there are different lineages. One factor that has caused confusion in Moa taxonomy is the intraspecific change in bone size between ice ages, as well as the extremely large sexual dimorphism in several species.
Interesting fact: Dinornis species probably have there was the most pronounced sexual dimorphism: females reach up to 150% of the height and up to 280% of the severity of males, so until 2003 they were classified as separate species. A 2009 study showed that Euryapteryx gravis and curtus are the same species, and in 2012 a morphological study interpreted them as subspecies.
DNA analyzes have determined that a number of mysterious evolutionary lines occurred in several genera of Moa. They may be classified as species or subspecies; M. benhami is identical to M. didinus because the bones of both have all the basic symbols. Size differences can be explained with their habitats combined with temporal inconsistencies. A similar temporary change in size is known in Pachyornis mappini from the North Island. The earliest remains of moas come from the Miocene fauna of Saint Batan.
Appearance and Features
The moa remains found were reconstructed into skeletons in a horizontal position to project the bird’s original height. An analysis of the joints of the vertebrae shows that in animals the head was tilted forward in a kiwi pattern. The spine was attached not to the base of the head, but to the back of it, indicating horizontal alignment. This gave them the ability to graze through low vegetation, but also be able to raise their heads and view the trees if necessary. This data led to a revision of the height of the larger moa.
Interesting fact: Some species of moa reached gigantic sizes. These birds did not have wings (they did not even have their rudiments). Scientists have identified 3 moa families and 9 species. The largest, D. robustus and D. novaezelandiae, grew to gigantic sizes relative to the currently existing birds, namely, their height was somewhere around 3.6 m, and their weight reached 250 kg.
Although no record of the moa’s vocalizations survives, some clues about their vocal calls can be inferred from the bird’s fossils. The tracheae of the MSCs in moas were supported by numerous rings of bones, known as tracheal rings.
The excavations of these rings showed that at least two genera of Moa (Emeus and Euryapteryx) had elongated tracheas, namely, their trachea reached 1 m in length and created a huge loop inside the body. They are the only birds that have this feature, in addition to this, several groups of birds that live today have a similar structure of the larynx, including: cranes, guinea fowls, mute swans. These characteristics are associated with a resonant deep sound that can reach great distances.
Where did the moa live?
Moa is endemic to New Zealand. An analysis of the fossil bones found has provided detailed data on the preferred habitat of specific moa species and revealed characteristic regional faunas.
Two species D. robustus and P elephantopus is native to the South Island.
They favored two main faunas:
- west coast beech forest fauna or Nothofagus with high rainfall;
- dry rain forest and scrub fauna east of the Southern Alps has been inhabited by species such as Pachyornis elephantopus (thick-legged moa), E. gravis, E. crassus, and D. robustus.
Two others South Island moa species, P. australis and M. didinus, may be included in the subalpine fauna along with the common D. robustus and P. australis.
Bones of the animal have been found in caves in the northwestern regions of Nelson and Karamea (such as Sota Hill Cave), as well as in some places in the Wanaka region. The species M. didinus was called the mountain moa because its bones are more often found in the subalpine zone. However, this also happened at sea level, where suitable steep and rocky terrain existed. Their distribution in coastal areas was unclear, but they were found in several locations such as Kaikoura, the Otago Peninsula, and Caritane.
Less information is available on the paleofaunas of the North Island due to the scarcity of fossil remains. The basic pattern of the relationship between moa and habitat was similar. Although some similar species (E. gravis , A. didiformis) lived on the South and North Islands, the majority belonged to only one island, which shows a divergence over several thousand years.
In the high rainfall forests of the North Island, D. novaezealandiae and A. didiformis dominated. Other moa species present on the North Island (E. gravis, E. curtus and P. geranoides) lived in drier forest and scrub areas. P. geranoides was found throughout the North Island, while the distribution of E. gravis and E. curtus were almost mutually exclusive, with the former only being found in coastal areas in the south of the North Island.
Now you know where she lived moa bird. Let’s see what she ate.
What does a moa eat?
No one has seen how and what the moa eats, however, their diet was restored by scientists from the fossilized contents of the stomachs of the animal, from the preserved droppings, and also indirectly as a result of the morphological analysis of skulls and beaks and the analysis of stable isotopes from their bones. The moa was known to feed on a range of plant species and plant parts, including fibrous twigs and leaves taken from low trees and shrubs. The mao’s beak was similar to a pair of secateurs and could cut the fibrous leaves of the New Zealand formium flax (Phórmium) and twigs with a diameter of at least 8 mm.
The moa on the islands filled an ecological niche that was occupied elsewhere by large mammals such as antelopes and llamas. Some biologists claim that a number of plant species have evolved to avoid moa viewing. Plants such as Pennantia have small leaves and a dense network of branches. In addition, pseudopanax thickifolia has tough, juvenile leaves, and is a possible example of a plant that has evolved.
Like many other birds, the moa swallowed stones (gastroliths) that were held in their muscular gizzards, providing a grinding action that allowed them to consume coarse plant material. The stones were generally smooth, round, and quartz-like, but stones over 110 mm long have been found among the preserved contents of the Mao’s stomach. Stomachs of birdscan often contain several kilograms of such stones. Moa was selective in choosing stones for the stomach and chose the hardest pebbles.
Character and lifestyle features
Because moa — this is a group of flightless birds, questions arose as to how these birds arrived in New Zealand and from where. There are many theories about the arrival of moa to the islands. The most recent theory suggests that the moa birds arrived in New Zealand about 60 million years ago and diverged from the “basal” moa species, Megalapteryxabout 5.8. This does not necessarily mean that there was no speciation between the arrival of 60 mya and the basal splitting of 5.8 mya, but fossils are missing and most likely the early lineages of the moa have disappeared.
Moa lost the ability to fly and began to move on foot, eating fruits, shoots, leaves and roots. Before humans, moa evolved into different species. In addition to gigantic moas, there were also small species that weighed up to 20 kg. About eight moa tracks have been found on the North Island with fossilized footprints in fluvial mud, including Waikane Creek (1872), Napier (1887), Manawatu River (1895), Palmerston North (1911), Rangitikei River ( 1939) and in Lake Taupo (1973). An analysis of the distance between the tracks shows that the walking speed of the moa was between 3 and 5 km/h.
Moa were clumsy animals that slowly moved their massive bodies. Their color did not stand out among the surrounding landscape. Based on the few remains of moa (muscles, skin, feathers) preserved by desiccation when the bird died in a dry place (for example, a cave with a dry wind blowing through it), some idea of u200bu200bneutral plumage has been drawn from these remains. moa. The plumage of mountain species was a denser layer to the very base, which covered the entire body area. This is probably how the bird adapted to life in high mountain snow conditions.
Social structure and reproduction
Moas are characterized by low fecundity and a long maturation period. Sexual maturity was most likely reached at about 10 years of age. Larger species took longer to reach adult size than smaller moa species, which had rapid skeletal growth. No evidence has been found that moa built nests. Accumulations of eggshell fragments have been found in caves and rock shelters, but almost no nests have been found. Excavations of rock shelters in the eastern part of the North Island during the 1940s unearthed small depressions apparently carved into soft, dry pumice.
Moa nesting material has also been excavated from rock shelters in the Central Otago area of the South Island, where the arid climate favored the preservation of the plant material used to build the nesting platform (including branches that were clipped with the moa’s beak. Seeds and pollen found on nesting material , show that the nesting season was late spring and summer.Moa eggshell fragments are often found in archaeological sites and sand dunes off the coast of New Zealand.
Thirty-six whole moa eggs kept in museum collections vary greatly in size (120–241 mm long, 91–179 mm wide). On the outer surface of the shell there are small slit-like pores. The eggshells of most moas are white, although mountain moas (M. didinus) have blue-green eggs.
Fun fact: A 2010 study found that some species of very fragile, only about a millimeter thick. Surprisingly, several thin-shelled eggs belong to the heaviest form of moa in the genus Dinornis and are the most fragile of all bird eggs known today.
Furthermore, external DNA isolated from eggshell surfaces shows that these thin eggs were most likely incubated by lighter males. The thin eggshell nature of the larger moa species suggests that the eggs of these species often cracked.
Moas’ natural enemies
Before the arrival of the Maori people, the only The moa’s predator was the huge Haast Eagle. New Zealand was isolated from the rest of the world for 80 million years and had few pre-human predators, meaning that its ecosystems were not only extremely fragile, but native species lacked adaptations to fight predators.
The Maori people arrived sometime before 1300, and the Moa lineage soon became extinct due to hunting them, to a lesser extent due to habitat reduction and deforestation. By 1445, all moas were extinct, along with Haast’s eagle, which fed on them. Recent studies using carbon have shown that the events that led to the extinction took less than a hundred years.
Interesting fact: Some scientists have suggested that several species of M. didinus could have survived in remote parts of New Zealand until the 18th and even 19th centuries, but this view was not widely accepted.
Maori observers have claimed that they were chasing birds as early as the 1770s, but these accounts most likely did not refer to the hunting of real birds, but to a now-lost ritual among the southern islanders. In the 1820s, a man named D. Pauley made an unconfirmed claim that he saw a moa in the Otago region of New Zealand.
An expedition in the 1850s led by Lieutenant A. Impi reported two emu-like birds on a hillside in the South Island. An 80-year-old woman, Alice Mackenzie, stated in 1959 that she saw moas in the bushes of Fiordland in 1887 and again on a Fiordland beach when she was 17 years old. She claimed that her brother also saw moas.
Population and species status
Moa bones found closest to us date back to 1445. Confirmed facts of the further existence of the bird have not yet been found. Periodically, there are speculations about the existence of moa in later periods. At the end of XIX — century, and more recently, in 2008 and 1993, some people testified that they saw moas in various places.
Interesting fact: The rediscovery of the takaha bird in 1948 after no one had seen it since 1898 demonstrated that rare species of birds can exist undetected for a long time. But still, the takaha is a much smaller bird than the moa, which is why experts continue to argue that moa are unlikely to survive.
The moa has often been cited as a potential candidate for resurrection through cloning. The cult status of the animal, combined with the fact that it went extinct only a few hundred years ago, i.e. a significant number of moa remains have survived, meaning that advances in cloning technology may allow moas to be resurrected. Pre-processing related to DNA extraction was done by Japanese geneticist Yasuyuki Chirota.
Interest in the moa’s potential for resurgence arose in mid-2014 when New Zealand MP Trevold Mellard proposed the restoration of small moa species. The idea was ridiculed by many, but nonetheless received support from several natural history experts.