39-458: Some 40 living, and see below . Rails (avian family Rallidae ) are a large, cosmopolitan family of small- to medium-sized terrestrial and/or semi-amphibious birds . The family exhibits considerable diversity in its forms, and includes such ubiquitous species as the crakes, coots , and gallinule ; other rail species are extremely rare or endangered. Many are associated with wetland habitats, some being semi-aquatic like waterfowl (such as
78-413: A cosmopolitan species is an endemic (native) species, or one that is found only in a single geographical location. Endemism usually results in organisms with specific adaptations to one particular climate or region, and the species would likely face challenges if placed in a different environment. There are far more examples of endemic species than cosmopolitan species; one example being the snow leopard ,
117-517: A persistently high ability to disperse long distances among tropic Pacific islands, though only the latter two gave rise to flightless endemic species throughout the Pacific Basin. In examining the phylogeny of G. philippensis , although the species is clearly polyphyletic (it has more than one ancestral species), it is not the ancestor of most of its flightless descendants, revealing that the flightless condition evolved in rails before speciation
156-659: A planet too large for local populations to interbreed routinely with each other include genetic effects such as ring species , such as in the Larus gulls, and the formation of clines such as in Drosophila . Cosmopolitan distributions can be observed both in extinct and extant species. For example, Lystrosaurus was cosmopolitan in the Early Triassic after the Permian-Triassic extinction event . In
195-527: A species found only in Central Asian mountain ranges, an environment to which the cats have adapted over millions of years. The caveat "in appropriate habitat" is used to qualify the term "cosmopolitan distribution", excluding in most instances polar regions, extreme altitudes, oceans, deserts, or small, isolated islands. For example, the housefly is highly cosmopolitan, yet is neither oceanic nor polar in its distribution. The term pandemism also
234-422: Is Swinhoe's rail , at 13 cm (5.1 in) and 25 g. The larger species are also sometimes given other names. The black coots are more adapted to open water than their relatives, and some other large species are called gallinules and swamphens. The largest of this group is the takahē , at 65 cm (26 in) and 2.7 kg (6.0 lb). The rails have suffered disproportionally from human changes to
273-467: Is a significant contributor to the rail's remarkably fast loss of flight; as few as 125,000 years were needed for the Laysan rail to lose the power of flight and evolve the reduced, stubby wings only useful to keep balance when running quickly. Indeed, some argue that measuring the evolution of flightlessness in rails in generations rather than millennia might be possible. Another factor that contributes to
312-532: Is extinct) Crex – corn crake Lewinia – rails (4 species) Aptenorallus – Calayan rail Habroptila – invisible rail Gallirallus – weka Eulabeornis – chestnut rail Hypotaenidia – rails and woodhen (12 species of which 4 are extinct) Himantornis – Nkulengu rail Porzana – crakes and sora (3 species) Tribonyx – nativehens (2 species) Paragallinula – lesser moorhen Gallinula – moorhens (7 species of which 2 are extinct) Fulica – coots (11 species of which 1
351-421: Is extinct) Porphyrio – swamphens, gallinules and takahes (12 species of which 2 are extinct) Micropygia – ocellated crake Rufirallus – crakes (2 species) Coturnicops – rails and a crake (3 species) Laterallus – crakes and rails (13 species) Cosmopolitan distribution In biogeography , a cosmopolitan distribution is the range of a taxon that extends across most or all of
390-539: Is home to some indigenous species within the Myrmeleontidae, but nonetheless no one species, nor even genus, of the Myrmeleontidae is cosmopolitan. Conversely, partly as a result of human introduction of unnatural apiculture to the New World, Apis mellifera probably is the only cosmopolitan member of its family; the rest of the family Apidae have modest distributions. Even where a cosmopolitan population
429-430: Is in use, but not all authors are consistent in the sense in which they use the term; some speak of pandemism mainly in referring to diseases and pandemics , and some as a term intermediate between endemism and cosmopolitanism, in effect regarding pandemism as subcosmopolitanism . This means near cosmopolitanism, but with major gaps in the distribution , say, complete absence from Australia. Terminology varies, and there
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#1732779695739468-418: Is one of the best examples of parallel evolution in the animal kingdom. Of the roughly 150 historically known rail species, 31 extant or recently extinct species evolved flightlessness from volant (flying) ancestors. This process created the endemic populations of flightless rails seen on Pacific islands today. Many island rails are flightless because small island habitats without mammalian predators eliminate
507-541: Is recognised as a single species, such as indeed Apis mellifera , there generally will be variation between regional sub-populations. Such variation commonly is at the level of subspecies , varieties or morphs , whereas some variation is too slight or inconsistent for formal recognition. For an example of subspecific variation, consider the East African lowland honey bee ( Apis mellifera scutellata )—best known for being hybridized with various European subspecies of
546-519: Is some debate whether the true opposite of endemism is pandemism or cosmopolitanism. A related concept in biogeography is that of oceanic cosmopolitanism and endemism. Rather than allow ubiquitous travel, the World Ocean is complicated by physical obstacles such as temperature gradients. These prevent migration of tropical species between the Atlantic and Indian/Pacific oceans. Conversely,
585-584: Is the anglicized respelling of the French râle , from Old French rasle . It is named from its harsh cry, in Vulgar Latin * rascula , from Latin rādere ("to scrape"). The rails are a family of small to medium-sized, ground-living birds. They vary in length from 12 to 63 cm (5 to 25 in) and in weight from 20 to 3,000 g (0.7 oz to 6 lb 10 oz). Some species have long necks and in many cases are laterally compressed. The bill
624-561: Is the most variable feature within the family. In some species, it is longer than the head (like the clapper rail of the Americas ); in others, it may be short and wide (as in the coots ), or massive (as in the purple gallinules ). A few coots and gallinules have a frontal shield , which is a fleshy, rearward extension of the upper bill. The most complex frontal shield is found in the horned coot . Rails exhibit very little sexual dimorphism in either plumage or size. Two exceptions are
663-599: The American purple gallinule , have been considered pests . Due to their tendencies towards flightlessness, many island species have been unable to cope with introduced species. The most dramatic human-caused extinctions occurred in the Pacific Ocean as people colonised the islands of Melanesia , Polynesia , and Micronesia , during which an estimated 750–1800 species of birds became extinct, half of which were rails. Some species that came close to extinction, such as
702-485: The Arctic Circle to Antarctica and every coastal and open-water region in-between. Such a taxon (usually a species ) is said to have a cosmopolitan distribution, or exhibit cosmopolitanism , as a species; another example, the rock dove (commonly referred to as a ' pigeon '), in addition to having been bred domestically for centuries, now occurs in most urban areas around the world. The extreme opposite of
741-569: The Arctic tern occur from the Arctic to the Southern Ocean , but at any one season of the year they are likely to be largely in passage or concentrated at only one end of the range. Also, some such species breed only at one end of the range. Seen purely as an aspect of cosmopolitanism, such distributions could be seen as temporal, seasonal variations. Other complications of cosmopolitanism on
780-455: The Lord Howe woodhen , and the takahē, have made modest recoveries due to the efforts of conservation organisations. The Guam rail came perilously close to extinction when brown tree snakes were introduced to Guam , but some of the last remaining individuals were taken into captivity and are breeding well, though attempts at reintroduction have met with mixed results. The family Rallidae
819-650: The watercock ( Gallicrex cinerea ) and the little crake ( Zapornia parva ). The wings of all rails are short and rounded. The flight of those Rallidae able to fly, while not powerful, can be sustained for long periods of time, and many species migrate annually. The weakness of their flight, however, means they are easily blown off course, thus making them common vagrants , a characteristic that has led them to colonize many isolated oceanic islands. Furthermore, these birds often prefer to run rather than fly, especially in dense habitat. Some are also flightless at some time during their moult periods. Flightlessness in rails
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#1732779695739858-483: The western honey bee to create the so-called " African killer bee "—and the Cape bee , which is the subspecies Apis mellifera capensis ; both of them are in the same cosmopolitan species Apis mellifera , but their ranges barely overlap. Other cosmopolitan species, such as the house sparrow and osprey , present similar examples, but in yet other species there are less familiar complications: some migratory birds such as
897-555: The Northern marine regions and Southern Ocean are separated by the tropics , too warm for many species to traverse. Another aspect of cosmopolitanism is that of ecological limitations. A species that is apparently cosmopolitan because it occurs in all oceans might in fact occupy only littoral zones , or only particular ranges of depths, or only estuaries , for example. Analogously, terrestrial species might be present only in forests, or mountainous regions, or sandy arid regions or
936-502: The coot), but many more are wading birds or shorebirds. The ideal rail habitats are marsh areas, including rice paddies , and flooded fields or open forest. They are especially fond of dense vegetation for nesting. The rail family is found in every terrestrial habitat with the exception of dry desert , polar or freezing regions, and alpine areas (above the snow line ). Members of Rallidae occur on every continent except Antarctica . Numerous unique island species are known. "Rail"
975-573: The environment, and an estimated several hundred species of island rails have become extinct because of this. Several island species of rails remain endangered , and conservation organisations and governments continue to work to prevent their extinction. The breeding behaviors of many Rallidae species are poorly understood or unknown. Most are thought to be monogamous , although polygyny and polyandry have been reported. Most often, they lay five to 10 eggs . Clutches as small as one or as large as 15 eggs are known. Egg clutches may not always hatch at
1014-431: The evolution of multiple sizes of flightless rails on the same island as the birds diversify to fill niches. In addition to energy conservation, certain morphological traits also affect rail evolution. Rails have relatively small flight muscles and wings to begin with. In rails, the flight muscles make up only 12–17% of their overall body mass. This, in combination with their terrestrial habits and behavioral flightlessness,
1053-589: The family to ordinal level as the Ralliformes. Given uncertainty about gruiform monophyly , this may or may not be correct; it certainly seems more justified than most of the Sibley-Ahlquist proposals. However, such a group would probably also include the Heliornithidae (finfoots and sungrebes), an exclusively tropical group that is somewhat convergent with grebes , and usually united with
1092-483: The introduction of terrestrial predators such as cats , foxes , weasels , mongooses , rats , and pigs . Many reedbed species are secretive (apart from loud calls), crepuscular , and have laterally flattened bodies. In the Old World , long-billed species tend to be called rails and short-billed species crakes. North American species are normally called rails irrespective of bill length. The smallest of these
1131-430: The like. Such distributions might be patchy, or extended, but narrow. Factors of such a nature are taken widely for granted, so they seldom are mentioned explicitly in mentioning cosmopolitan distributions. Cosmopolitanism of a particular species or variety should not be confused with cosmopolitanism of higher taxa. For example, the family Myrmeleontidae is cosmopolitan in the sense that every continent except Antarctica
1170-526: The modern world, the orca , the blue whale , and the great white shark all have cosmopolitan distribution, extending over most of the Earth's oceans . The wasp Copidosoma floridanum is another example, as it is found around the world. Other examples include humans , cats , dogs , the western honey bee , brown rats , the foliose lichen Parmelia sulcata , and the mollusc genus Mytilus . The term can also apply to some diseases. It may result from
1209-412: The need to fly or move long distances. Flight makes intense demands, with the keel and flight muscles taking up to 40% of a bird's weight. Reducing the flight muscles, with a corresponding lowering of metabolic demands, reduces the flightless rail's energy expenditures. For this reason, flightlessness makes it easier to survive and colonize an island where resources may be limited. This also allows for
Rail (bird) - Misplaced Pages Continue
1248-542: The occurrence of the flightless state is a climate that does not necessitate seasonal long-distance migration; this is evidenced by the tendency to evolve flightlessness at a much greater occurrence in tropical islands than in temperate or polar islands. It is paradoxical, since rails appear loath to fly, that the evolution of flightless rails would necessitate high dispersal to isolated islands. Nonetheless, three species of small-massed rails, Gallirallus philippensis , Porphyrio porphyrio , and Porzana tabuensis , exhibit
1287-794: The population as an entirety, rather than many young that would exhibit less fitness. Unfortunately, with the human occupation of most islands in the past 5,000 to 35,000 years, selection has undoubtedly reversed the tolerance into a wariness of humans and predators, causing species unequipped for the change to become susceptible to extinction. In general, members of the Rallidae are omnivorous generalists. Many species eat invertebrates , as well as fruit or seedlings. A few species are primarily herbivorous . The calls of Rallidae species vary and are often quite loud. Some are whistle-like or squeak-like, while others seem unbirdlike. Loud calls are useful in dense vegetation, or at night where seeing another member of
1326-914: The rails in the Ralli. The cladogram below showing the phylogeny of the living and recently extinct Rallidae is based on a study by Juan Garcia-R and collaborators published in 2020. The genera and number of species are taken from the list maintained by Frank Gill , Pamela Rasmussen and David Donsker on behalf of the International Ornithological Committee (IOC). The names of the subfamilies and tribes are those proposed by Jeremy Kirchman and collaborators in 2021. Neocrex – crakes (2 species) Pardirallus – rails (3 species) Amaurolimnas – uniform crake Aramides – rails (8 species) Rallus – rails (14 species) Crecopsis – African crake Rougetius – Rouget's rail Dryolimnas – rails (2 species of which 1
1365-414: The same time. Chicks become mobile after a few days. They often depend on their parents until fledging, which happens around 1 month old. Some larger, more abundant rails are hunted and their eggs collected for food. The Wake Island rail was hunted to extinction by the starving Japanese garrison after the island was cut off from supply during World War II . At least two species, the common moorhen and
1404-711: The species is difficult. Some calls are territorial . The most typical family members occupy dense vegetation in damp environments near lakes , swamps , or rivers . Reed beds are a particularly favoured habitat. Those that migrate do so at night. Most nest in dense vegetation. In general, they are shy, secretive, and difficult to observe. Most species walk and run vigorously on strong legs, and have long toes that are well adapted to soft, uneven surfaces. They tend to have short, rounded wings, and although they are generally weak fliers , they are, nevertheless, capable of covering long distances. Island species often become flightless , and many of them are now extinct following
1443-413: The surface of the Earth, in appropriate habitats ; most cosmopolitan species are known to be highly adaptable to a range of climatic and environmental conditions, though this is not always so. Killer whales ( orcas ) are among the most well-known cosmopolitan species on the planet, as they maintain several different resident and transient (migratory) populations in every major oceanic body on Earth, from
1482-527: Was complete. A consequence of lowered energy expenditure in flightless island rails has also been associated with evolution of their "tolerance" and "approachability". For example, the (non-Rallidae) Corsican blue tits exhibit lower aggression and reduced territorial defense behaviors than do their mainland European counterparts, but this tolerance may be limited to close relatives. The resulting kin-selecting altruistic phenomena reallocate resources to produce fewer young that are more competitive and would benefit
1521-468: Was introduced (as Rallia) by the French polymath Constantine Samuel Rafinesque in 1815. The family has traditionally been grouped with two families of larger birds, the cranes and bustards , as well as several smaller families of usually "primitive" midsized amphibious birds, to make up the order Gruiformes . The alternative Sibley-Ahlquist taxonomy , which has been widely accepted in America, raises
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