The moa-nalo are a group of

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

aberrant,

goose A goose (: geese) is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera '' Anser'' (grey geese and white geese) and '' Branta'' (black geese). Some members of the Tadorninae subfamily (e.g., Egy ...

-like

duck Duck is the common name for numerous species of waterfowl in the family (biology), family Anatidae. Ducks are generally smaller and shorter-necked than swans and goose, geese, which are members of the same family. Divided among several subfam ...

s that lived on the larger

Hawaiian Islands The Hawaiian Islands () are an archipelago of eight major volcanic islands, several atolls, and numerous smaller islets in the Pacific Ocean, North Pacific Ocean, extending some from the Hawaii (island), island of Hawaii in the south to nort ...

, except

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

itself, in the Pacific. They were the major

herbivore A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...

s on most of these islands until they became extinct after human settlement.

Description

The moa-nalo (the name literally means "lost fowl"; the plural and the singular are the same) were long unknown to

science Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...

, having been wiped out before the arrival of

James Cook Captain (Royal Navy), Captain James Cook (7 November 1728 – 14 February 1779) was a British Royal Navy officer, explorer, and cartographer famous for his three voyages of exploration to the Pacific and Southern Oceans, conducted between 176 ...

(1778). In the early 1980s, their

subfossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

remains were discovered in

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...

s on the islands of

Molokai Molokai or Molokai ( or ; Molokaʻi dialect: Morotaʻi ) is the fifth most populated of the eight major islands that make up the Hawaiian Islands archipelago in the middle of the Pacific Ocean. It is 38 by 10 miles (61 by 16 km) at its g ...

and

Kauai Kauai (), anglicized as Kauai ( or ), is one of the main Hawaiian Islands. It has an area of 562.3 square miles (1,456.4 km2), making it the fourth-largest of the islands and the 21st-largest island in the United States. Kauai lies 73 m ...

. Subsequently, bones were found on

Maui Maui (; Hawaiian language, Hawaiian: ) is the second largest island in the Hawaiian archipelago, at 727.2 square miles (1,883 km2). It is the List of islands of the United States by area, 17th-largest in the United States. Maui is one of ...

Oahu Oahu (, , sometimes written Oahu) is the third-largest and most populated island of the Hawaiian Islands and of the U.S. state of Hawaii. The state capital, Honolulu, is on Oahu's southeast coast. The island of Oahu and the uninhabited Northwe ...

, and Lānai, in

lava tube A lava tube, more rarely called a pyroduct, is a 'roofed conduit through which molten lava travels away from its vent'. If lava in the tube drains out, it will leave an empty cave. Lava tubes are common in low-viscosity volcanic systems. La ...

s, lake beds, and

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water ...

s. They represent four

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

in three

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

so far: * ''Chelychelynechen quassus'' (

turtle-jawed moa-nalo The turtle-jawed moa-nalo (''Chelychelynechen quassus''), also formerly referred to as the large Kauai goose, is a species of moa-nalo (a group of extinct, flightless, large goose-like ducks), which evolved in the Hawaiian Islands of the North P ...

) from Kauai * ''Ptaiochen pau'' (

small-billed moa-nalo The small-billed moa-nalo (''Ptaiochen pau''), also known as the stumbling moa-nalo, is a species of moa-nalo, one of a group of extinct, flightless, large goose-like ducks, which evolved in the Hawaiian Islands of the North Pacific Ocean. It was ...

) from Maui * ''Thambetochen xanion'' (

O'ahu moa-nalo Oahu (, , sometimes written Oahu) is the third-largest and most populated island of the Hawaiian Islands and of the U.S. state of Hawaii. The state capital, Honolulu, is on Oahu's southeast coast. The island of Oahu and the uninhabited Northwe ...

) from Oahu * ''Thambetochen chauliodous'' (

Maui Nui large-billed moa-nalo The Maui Nui large-billed moa-nalo (''Thambetochen chauliodous''), also known as the Maui Nui moa-nalo, is one of two species of moa-nalo in the genus ''Thambetochen''. Moa-nalo are a group of extinct, flightless, large goose-like ducks, which ev ...

) from Maui, Lānai and Molokai (

Maui Nui Maui Nui is a modern Geology, geologists' name given to a prehistoric Hawaii, Hawaiian island and the corresponding modern Biogeography, biogeographic region. Maui Nui is composed of four modern islands: Maui, Molokai, Molokaʻi, Lanai, Lānaʻi, ...

) ''Chelychelynechen'', meaning turtle-jawed goose, had a large, heavy bill like that of a

tortoise Tortoises ( ) are reptiles of the family Testudinidae of the order Testudines (Latin for "tortoise"). Like other turtles, tortoises have a shell to protect from predation and other threats. The shell in tortoises is generally hard, and like o ...

, while the other two genera, ''Thambetochen'' and ''Ptaiochen'', all had serrations in their bills known as pseudoteeth, similar to those of

merganser ''Mergus'' is the genus of the typical mergansers ( ) fish-eating ducks in the subfamily Anatinae. The genus name is a Latin word used by Pliny the Elder and other Roman authors to refer to an unspecified waterbird. The common merganser (''Mer ...

s. All species were

flightless Flightless birds are birds that cannot fly, as they have, through evolution, lost the ability to. There are over 60 extant species, including the well-known ratites ( ostriches, emus, cassowaries, rheas, and kiwis) and penguins. The smal ...

and large, with an average mass of .

Evolution

Some moa-nalo fossils have been found to contain traces of

mitochondrial DNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the D ...

which were compared to living duck species in order to establish their place in the duck family,

Anatidae The Anatidae are the biological family (biology), family of water birds that includes ducks, goose, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted f ...

. Contrary to the expectations of some scientists, the moa-nalo were not related to the large

geese A goose (: geese) is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera '' Anser'' (grey geese and white geese) and ''Branta'' (black geese). Some members of the Tadorninae subfamily (e.g., Egyp ...

(

Anserinae The Anserinae are a subfamily in the waterfowl family Anatidae. It includes the swans and the true Goose, geese. Under alternative systematics, systematical concepts (see e.g., Terres & NAS, 1991), it is split into two subfamilies, the Anserina ...

), such as the surviving

nēnē The Nene (''Branta sandvicensis''), also known as the nēnē or the Hawaiian goose, is a species of bird Endemism in birds, endemic to the Hawaiian Islands. The Nene is exclusively found in the wild on the islands of Maui, Kauai, Kauai, Molokai, ...

, but instead to the

dabbling duck The Anatinae are a subfamily of the family Anatidae (swans, geese and ducks). Its surviving members are the dabbling ducks, which feed mainly at the surface rather than by diving. The other members of the Anatinae are the extinct moa-nalo, a y ...

s of the genus ''

Anas ''Anas'' is a genus of dabbling ducks. It includes the pintails, most teals, and the mallard and its close relatives. It formerly included additional species but following the publication of a molecular phylogenetic study in 2009 the genus was s ...

'', which includes the

mallard The mallard () or wild duck (''Anas platyrhynchos'') is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa. It has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Arge ...

. The present DNA analysis' resolution is not high enough to determine their relationships to different species of ''

'', but

biogeography Biogeography is the study of the species distribution, distribution of species and ecosystems in geography, geographic space and through evolutionary history of life, geological time. Organisms and biological community (ecology), communities o ...

strongly suggests that their closest living relative is the widespread

Pacific black duck The Pacific black duck (''Anas superciliosa''), commonly known as the PBD, is a dabbling duck found in much of Indonesia, New Guinea, Australia, New Zealand, and many islands in the southwestern Pacific, reaching to the Caroline Islands in the no ...

Ecology

The unusual bill shape and size of the moa-nalo can be attributed to their role in the

ecology Ecology () is the natural science of the relationships among living organisms and their Natural environment, environment. Ecology considers organisms at the individual, population, community (ecology), community, ecosystem, and biosphere lev ...

of prehistoric Hawaii. A study of

coprolite A coprolite (also known as a coprolith) is fossilized feces. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour (in this case, diet) rather than morphology. The name ...

s (fossil dung) of ''Thambetochen chauliodous'' found in Puu Naio Cave on lowland Maui has shown they were folivorous, at least in dry shrub or

mesic forest In ecology, a mesic habitat is a type of habitat with a well-balanced or moderate supply of moisture throughout the growing season (e.g., a mesic forest, temperate hardwood forest, or dry-mesic prairie). The term derives from the Greek ''mesos'' ...

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

s eating particularly fronds from

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

s (possibly ''

Asplenium nidus ''Asplenium nidus'' is an epiphytic species of fern in the family Aspleniaceae, native to tropical southeastern Asia, eastern Australia, Hawaii (''ʻēkaha'' in Hawaiian), Polynesia,MacDonald, Elvin "The World Book of House Plants" pp.264 Popul ...

'' or ''

Dryopteris wallichiana ''Dryopteris wallichiana'', the alpine wood fern, is a robust species of deciduous or semi-evergreen fern in the family (biology), family Dryopteridaceae, native plant, native to the Himalayas, Hawaii, Mexico and Jamaica. It grows to tall, occas ...

''). This conclusion is backed up by the shapes of their beaks (James & Burney 1997). This indicates they were the principal browsers on the island. The presence of prominent spines on the leaves and soft young stems of several

Hawaiian lobelioids The Hawaiian lobelioids are a group of flowering plants in the bellflower family, Campanulaceae, subfamily Lobelioideae, all of which are endemic to the Hawaiian Islands. This is the largest plant radiation in the Hawaiian Islands, and indeed t ...

in the genus '' Cyanea''—unusual in an island flora where such defenses are frequently lost, as in the '' ākala'' (Hawaiian

raspberry The raspberry is the edible fruit of several plant species in the genus ''Rubus'' of the Rosaceae, rose family, most of which are in the subgenus ''Rubus#Modern classification, Idaeobatus''. The name also applies to these plants themselves. Ras ...

)—suggests that the ''Cyanea'' evolved these thornlike prickles on new growth because they protect against browsing by the moa-nalo. The moa-nalo themselves filled the niche of herbivore usually filled by mammals such as

goat The goat or domestic goat (''Capra hircus'') is a species of Caprinae, goat-antelope that is mostly kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the ...

s and

deer A deer (: deer) or true deer is a hoofed ruminant ungulate of the family Cervidae (informally the deer family). Cervidae is divided into subfamilies Cervinae (which includes, among others, muntjac, elk (wapiti), red deer, and fallow deer) ...

, or the

giant tortoise Giant tortoises are any of several species of various large land tortoises, which include a number of extinct species, as well as two extant species with multiple subspecies formerly common on the islands of the western Indian Ocean and on the ...

s of Galápagos and other

archipelago An archipelago ( ), sometimes called an island group or island chain, is a chain, cluster, or collection of islands. An archipelago may be in an ocean, a sea, or a smaller body of water. Example archipelagos include the Aegean Islands (the o ...

es. This has implications for the ecology of Hawaiian Islands today, as a major group of species have been lost. Like island

taxa In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

from

Mauritius Mauritius, officially the Republic of Mauritius, is an island country in the Indian Ocean, about off the southeastern coast of East Africa, east of Madagascar. It includes the main island (also called Mauritius), as well as Rodrigues, Ag ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

and

Polynesia Polynesia ( , ) is a subregion of Oceania, made up of more than 1,000 islands scattered over the central and southern Pacific Ocean. The indigenous people who inhabit the islands of Polynesia are called Polynesians. They have many things in ...

, the moa-nalo were unused to

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s and were easily predated on by hunters or the animals that were introduced and became

feral A feral (; ) animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in som ...

, such as

domestic pig The pig (''Sus domesticus''), also called swine (: swine) or hog, is an omnivorous, domesticated, even-toed, hoofed mammal. It is named the domestic pig when distinguishing it from other members of the genus '' Sus''. Some authorities cons ...

References

* James, Helen F. & Burney, David A. (1997): The diet and ecology of Hawaii's extinct flightless waterfowl: evidence from coprolites. '' Biol. J. Linn. Soc.'' 62(2): 279–297
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Description

Evolution

Ecology

See also

References