Flightless bird - wikipedia Flightless bird Penguins are a well - known example of flightless birds Flightless birds are birds that through evolution lost the ability to fly. There are over 60 extant species including the well known ratites ( ostrich, emu, cassowary, rhea and kiwi ) and penguins. The smallest flightless bird is the Inaccessible Island rail ( length 12.5 cm, weight 34.7 g ). The largest ( both heaviest and tallest ) flightless bird, which is also the largest living bird, is the ostrich ( 2.7 m, 156 kg ). Ostriches are farmed for their decorative feathers, meat and their skins, which are used to make leather. Many domesticated birds, such as the domestic chicken and domestic duck, have lost the ability to fly for extended periods, although their ancestral species, the red junglefowl and mallard, respectively, are capable of extended flight. A few particularly bred birds, such as the Broad Breasted White turkey, have become totally flightless as a result of selective breeding ; the birds were bred to grow massive breast meat that weighs too much for the bird 's wings to support in flight. Flightlessness has evolved in many different birds independently. There were also other families of flightless birds, such as the now extinct Phorusrhacidae, that evolved to be powerful terrestrial predators. Taking this to a greater extreme, the terror birds ( and their relatives the bathornithids ), eogruids, gastornithiforms, and dromornithids ( all extinct ) all evolved similar body shapes -- long legs, long necks and big heads -- but none of them were closely related. Furthermore, they also share traits of being giant, flightless birds with vestigial wings, long legs, and long necks with some of the ratites, although they are not related. Contents 1 Origins of flightlessness 1.1 Independent evolution of flightlessness in Paelaeognathes 2 Morphological changes and energy conservation 2.1 Continued presence of wings in flightless birds 3 List of flightless birds 3.1 Ratites 3.2 Anseriformes ( waterfowl ) 3.3 Galliformes ( game birds ) 3.4 Podicipediformes ( grebes ) 3.5 Pelecaniformes ( pelicans, cormorants and allies ) 3.6 Sphenisciformes ( penguins ) 3.7 Coraciiformes ( kingfishers, hornbills and allies ) 3.8 Ciconiiformes 3.9 Gruiformes ( cranes, rails, and coots ) 3.10 Mesitorniformes ( mesites ) 3.11 Charadriiformes ( gulls, terns, auks ) 3.12 Falconiformes ( birds of prey ) 3.13 Psittaciformes ( parrots ) 3.14 Columbiformes ( pigeons, doves ) 3.15 Caprimulgiformes ( nightjars ) 3.16 Strigiformes ( owls ) 3.17 Passeriformes ( perching birds ) 4 See also 5 References 6 External links Origins of flightlessness Divergences and losses of flight within ratite lineage occurred right after the K - Pg extinction event wiped out all non-avian dinosaurs and large vertebrates 66 million years ago. The immediate evacuation of niches following the mass extinction provided opportunities for Palaeognathes to distribute and occupy novel environments. New ecological influences selectively pressured different taxon to converge on flightless modes of existence by altering them morphologically and behaviorally. The successful acquisition and protection of a claimed territory selected for large size and cursoriality in Tertiary ancestors of ratites Temperate rainforests dried out throughout the Miocene and transformed into semiarid deserts causing habitats to be widely spread across the growingly disparate landmasses. Cursoriality was an economic means of traveling long distances to acquire food that was usually low lying vegetation, more easily accessed by walking Traces of these events are reflected in ratite distribution throughout semiarid grasslands and deserts today Gigantism and flightlessness are almost exclusively correlated. This is mostly observed in islands lacking predators and competition. However, ratites occupy environments that are mostly occupied by a diverse number of mammals. It is thought that they first originated through allopatric speciation caused by breakup of the supercontinent Gondwana. However recent evidence suggests this hypothesis first proposed by Joel Cracraft in 1974 is incorrect. Rather ratites arrived in their respective locations via a flighted ancestor and lost the ability to fly multiple times within the lineage. Gigantism is not a requirement for flightlessness. The kiwi does not exhibit gigantism, along with tinamous, even though they coexisted with the moa and rhea that both exhibit gigantism. This could be the result of different ancestral flighted birds arrival or because of competitive exclusion. The first flightless bird to arrive in each environment utilized the large flightless herbivore or omnivore niche, forcing the later arrivals to remain smaller. In environments where flightless birds are not present, it is possible that after the K / T Boundary there were no niches for them to fill. They were pushed out by other herbivorous mammals. New Zealand had more species of flightless birds ( including the kiwi, several species of penguins, the takahe, the moa, and several other extinct species ) than any other such location. One reason is that until the arrival of humans roughly a thousand years ago, there were no large land predators in New Zealand ; the main predators of flightless birds were larger birds. Independent evolution of flightlessness in paelaeognathes Ratites belong to the superorder Palaeognathae birds, which include the volant tinamou, and are believed to have evolved flightlessness independently multiple times within their own group. Some birds evolved flightlessness in response to the absence of predators, for example on oceanic islands. Incongruences between ratite phylogeny and Gondwana geological history indicate the presence of ratites in their current locations is the result of a secondary invasion by flying birds. It remains possible that the most recent common ancestor of ratites was flightless and the tinamou regained the ability to fly However, it is believed that the loss of flight is an easier transition for birds rather than the loss and regain of flight, which has never been documented in avian history. Moreover, tinamou nesting within flightless ratites indicates ancestral ratites were volant and multiple losses of flight occurred independently throughout the lineage. This indicates that the distinctive flightless nature of ratites is the result of convergent evolution. Morphological changes and energy conservation Two key differences between flying and flightless birds are the smaller wing bones of flightless birds and the absent ( or greatly reduced ) keel on their breastbone. ( The keel anchors muscles needed for wing movement. ). Adapting to a cursorial lifestyle causes two inverse morphological changes to occur in the skeleto - muscular system : the pectoral apparatus used to power flight is paedorphically reduced while peramorphosis leads to enlargement of the pelvic girdle for running Repeated selection for cursorial traits across ratites suggests these adaptions comprise a more efficient use of energy in adulthood The name `` ratite '' refers to their flat sternum that is distinct from the typical sternum of flighted birds because it lacks the keel. This structure is the place where flight muscles attach and thus allow for powered flight Though, ratite anatomy presents other primitive characters meant for flight such as the fusion of wing elements, a cerebellar structure, the presence of a pygostyle for tail feathers and an alula on the wing These morphological traits suggest some affinities to volant groups. Palaeognathes were one of the first colonizers of novel niches and were free to increase in abundance until the population was limited by food and territory. A study looking at energy conservation and the evolution of flightlessness hypothesized intraspecific competition selected for a reduced individual energy expenditure, which is achieved by the loss of flight Some flightless varieties of island birds are closely related to flying varieties, implying flight is a significant biological cost. Flight is the most costly type of locomotion exemplified in the natural world. The energy expenditure required for flight increases proportionally with body size, which is often why flightlessness coincides with body mass By reducing large pectoral muscles that require a significant amount of overall metabolic energy, ratites decrease their basal metabolic rate and conserve energy. A study looking at the basal rates of birds found a significant correlation between low basal rate and pectoral muscle mass in kiwis. On the contrary, flightless penguins exude an intermediate basal rate. This is likely because penguins have well - developed pectoral muscles for hunting and diving in the water For ground feeding birds, a cursorial lifestyle is more economical and allows for easier access to dietary requirements Flying birds have different wing and feather structures that make flying easier, while flightless birds ' wing structures are well adapted to their environment and activities, such as diving in the ocean. A number of bird species appear to be in the process of losing their powers of flight to various extents. These include the Zapata rail of Cuba, the Okinawa rail of Japan, and the Laysan duck of Hawaii. All of these birds show adaptations common to flightlessness, and evolved recently from flying ancestors, but have not yet fully given up the use of their wings. They are, however, weak flyers and are incapable of traveling long distances by air. Continued presence of wings in flightless birds Although selection pressure for flight was largely absent, the wing structure has not been lost except in the New Zealand moas. Ostriches are the fastest running birds in the world and emus have been documented running 50 km / hr At these high speeds, wings are necessary for balance and serving as a parachute apparatus to help the bird slow down. Wings are hypothesized to have played a role in sexual selection in early ancestral ratites and were thus maintained. This can be seen today in both the rheas and ostriches. These ratites utilize their wings extensively for courtship and displays to other males. Sexual selection also influences the maintenance of large body size, which discourages flight. The large size of ratites leads to greater access to mates and higher reproductive success. Ratites and tinamous are monogamous and mate only a limited number of times per year. High parental involvement denotes the necessity for choosing a reliable mate. In a climactically stable habitat providing year round food supply, a male 's claimed territory signals to females the abundance of resources readily available to her and her offspring. Male size also indicates his protective abilities. Similar to the emperor penguin, male ratites incubate and protect their offspring anywhere between 85 -- 92 days while females feed. They can go up to a week without eating and survive only off fat stores. The emu has been documented fasting as long as 56 days. If no continued pressures warrant the energy expenditure to maintain the structures of flight, selection will tend towards these other traits. List of flightless birds Many flightless birds are extinct ; this list shows species that are either still extant, or became extinct in the Holocene ( no more than 11,000 years ago ). Extinct species are indicated with a dagger ( † ). A number of species that are suspected, but not confirmed to be flightless, are also included here. Ratites Common Ostrich North Island brown kiwi Ostriches Common ostrich, Struthio camelus Somali ostrich, Struthio molybdophanes Asian ostrich, Struthio asiaticus † Emus Emu, Dromaius novaehollandiae King Island emu, Dromaius novaehollandiae minor † Kangaroo Island emu, Dromaius baudinianus † Tasmanian emu, Dromaius novaehollandiae diemenensis † Cassowaries Dwarf cassowary, Casuarius bennetti Southern cassowary, Casuarius casuarius Northern cassowary, Casuarius unappendiculatus Moa ( Dinornithiformes ) † Elephant birds ( Aepyornithiformes ) † Kiwis Southern brown kiwi, Apteryx australis Great spotted kiwi, Apteryx haastii North Island brown kiwi, Apteryx mantelli Little spotted kiwi, Apteryx owenii Okarito kiwi, Apteryx rowi Rheas Greater rhea, Rhea americana Darwin 's rhea, Rhea pennata Anseriformes ( waterfowl ) Campbell teal Auckland Island teal, Anas aucklandica Campbell teal, Anas nesiotis Steamer ducks Fuegian steamer duck, Tachyeres pteneres Falkland steamer duck, Tachyeres brachypterus Chubut steamer duck, Tachyeres leucocephalus Amsterdam wigeon, Anas marecula † Bermuda flightless duck, Anas pachyscelus † Finsch 's duck, Chenonetta finschi † New Zealand merganser, Mergus australis † Turtle - jawed moa - nalo, Chelychelynechen quassus † Small - billed moa - nalo, Ptaiochen pau † O'ahu moa - nalo, Thambetochen xanion † Maui Nui large - billed moa - nalo, Thambetochen chauliodous † Nēnē - nui, Branta hylobadistes † ( possibly flightless or very weak flier ) Mihirung, Genyornis newtoni † California flightless sea - duck, Chendytes lawi † Kaua'i mole duck, Talpanas lippa † New Zealand geese, Cnemiornis † Galliformes ( game birds ) New Caledonian giant scrubfowl, Sylviornis neocaledoniae † Noble megapode, Megavitornis altirostris † Viti Levu scrubfowl, Megapodius amissus † Podicipediformes ( grebes ) Junin grebe, Podiceps taczanowskii Titicaca grebe, Rollandia microptera Atitlán grebe, Podilymbus gigas † ( reportedly flightless ) Pelecaniformes ( pelicans, cormorants and allies ) Flightless cormorant Flightless cormorant, Phalacrocorax harrisi Jamaican ibis, Xenicibis xymphithecus † Apteribis, A. glenos and A. brevis † Sphenisciformes ( penguins ) King penguin, Aptenodytes patagonicus Emperor penguin, Aptenodytes forsteri Adélie penguin, Pygoscelis adeliae Chinstrap penguin, Pygoscelis antarctica Gentoo penguin, Pygoscelis papua Little blue penguin, Eudyptula minor White - flippered penguin, Eudyptula minor albosignata Magellanic penguin, Spheniscus magellanicus Humboldt penguin, Spheniscus humboldti Galapagos penguin, Spheniscus mendiculus African penguin, Spheniscus demersus Yellow - eyed penguin, Megadyptes antipodes Waitaha penguin, Megadyptes waitaha † Fiordland penguin, Eudyptes pachyrhynchus Snares penguin, Eudyptes robustus Erect - crested penguin, Eudyptes sclateri Rockhopper penguin, Eudyptes chrysocome Royal penguin, Eudyptes schlegeli Macaroni penguin, Eudyptes chrysolophus Chatham penguin, Eudyptes sp. † Coraciiformes ( kingfishers, hornbills and allies ) Saint Helena hoopoe, Upupa antaios † Ciconiiformes Ascension night heron, Nycticorax olsoni † Gruiformes ( cranes, rails, and coots ) Weka Great auk Cuban flightless crane, Grus cubensis † Red rail, Aphanapteryx bonasia † Rodrigues rail, Erythromachus leguati † Woodford 's rail, Nesoclopeus woodfordi ( most likely flightless ) Bar - winged rail, Nesoclopeus poecilopterus † ( probably flightless ) Weka, Gallirallus australis New Caledonian rail, Gallirallus lafresnayanus ( likely † ) Lord Howe woodhen, Gallirallus sylvestris Calayan rail, Gallirallus calayanensis Pink - legged rail, Gallirallus insignis Guam rail, Gallirallus owstoni Roviana rail, Gallirallus rovianae ( flightless, or almost so ) Tahiti rail, Gallirallus pacificus † Dieffenbach 's rail, Gallirallus dieffenbachii † Chatham rail, Cabalus modestus † Wake Island rail, Gallirallus wakensis † Snoring rail, Aramidopsis plateni Inaccessible Island rail, Atlantisia rogersi Laysan rail, Porzana palmeri † Hawaiian rail, Porzana sandwichensis † Kosrae crake, Porzana monasa † Ascension crake, Mundia elpenor † Henderson crake, Porzana atra Invisible rail, Habroptila wallacii New Guinea flightless rail, Megacrex inepta Lord Howe swamphen, Porphyrio albus † North Island takahē, Porphyrio mantelli † Takahē, Porphyrio hochstetteri Samoan woodhen, Gallinula pacifica Makira woodhen, Gallinula silvestris Tristan moorhen, Gallinula nesiotis † Gough Island moorhen, Gallinula comeri Tasmanian native hen, Tribonyx mortierii Giant coot, Fulica gigantea ( adults only ; immature birds can fly ) Hawkins ' rail, Diaphorapteryx hawkinsi † Snipe - rail, Capellirallus karamu † Adzebills, Aptornis otidiformis and A. defossor † Mesitorniformes ( mesites ) Brown mesite Mesitornis unicolor ( possibly flightless, has not been seen flying ) Charadriiformes ( gulls, terns, auks ) Great auk, Pinguinus impennis † Falconiformes ( birds of prey ) Dodo Jamaican caracara, Caracara tellustris † Psittaciformes ( parrots ) Kakapo, Strigops habroptilus Columbiformes ( pigeons, doves ) Dodo, Raphus cucullatus † Rodrigues solitaire, Pezophaps solitaria † Viti Levu giant pigeon, Natunaornis gigoura † Saint Helena dove, Dysmoropelia dekarchiskos † Henderson ground dove, Gallicolumba leonpascoi † Caprimulgiformes ( nightjars ) New Zealand owlet - nightjar, Aegotheles novaezealandiae † Strigiformes ( owls ) Cuban giant owl, Ornimegalonyx spp. † ( possibly flightless ) Cretan owl, Athene cretensis † ( probably flightless ) Andros Island barn owl, Tyto pollens † ( possibly flightless ) Passeriformes ( perching birds ) Lyall 's wren, Xenicus lyalli † Long - billed wren, Dendroscansor decurvirostris † North Island stout - legged wren, Pachyplichas jagmi † South Island stout - legged wren, Pachyplichas yaldwyni † Long - legged bunting, Emberiza alcoveri † See also Birds portal Biology portal Origin of birds : Secondary flightlessness in dinosaurs List of extinct birds Gastornis Phorusrhacidae Dromornithidae References Jump up ^ `` New Zealand Ecology -- Moa ''. TerraNature. Retrieved 2007 - 08 - 27. ^ Jump up to : `` The Bird Site : Flightless Birds ''. Archived from the original on 2007 - 07 - 13. Retrieved 2007 - 08 - 27. ^ Jump up to : Harshman, John ; Braun, Edward L. ; et al. ( 2 September 2008 ). `` Phylogenomic evidence for multiple losses of flight in ratite birds ''. PNAS. 105 ( 36 ) : 13462 -- 13467. doi : 10.1073 / pnas. 0803242105. PMC 2533212. PMID 18765814. Jump up ^ Holmes, Bob ( 2008 - 06 - 26 ). `` Bird evolutionary tree given a shake by DNA study ''. New Scientist. ^ Jump up to : Smith, J.V., Braun, E.L. and Kimball, R.T. ( 2012 ). `` Ratite non-monophyly : Independent evidence from 40 novel loci ''. Systematic Biology : sys067. CS1 maint : Multiple names : authors list ( link ) ^ Jump up to : Phillips, M.J., G.C. Gibb, E.A. Crimp and D. Penny ( 2010 ). `` Tinamous and moa flock together : mitochondrial genome sequence analysis reveals independent losses of flight among ratites. '' Systematic biology 59 : 90 - 107. ^ Jump up to : Noble, J.C. ( 1991 ). `` On ratites and their interactions with plants. '' Revista Chilena de Historia Natural 64 : 85 - 118. ^ Jump up to : Mitchell, K., Llamas B., Soubrier J., Rawlence N., Worthy T., Wood J., Lee M., Cooper A. ( 2014 ). Ancient DNA Reveals Elephant Birds and Kiwi are Sister Taxa and Clarifies Ratite Bird Evolution. Science Magazine ( Internet ). ( April 24, 2014, cited 2014 Oct. 28 ). Jump up ^ Baker, A.J, Haddrath O., Cloutier A, Mcpherson J.D. ( 2014 ) ^ Jump up to : Cracraft, J. ( 1974 ). `` Phylogeny and evolution of the ratite birds. '' International journal of avian science 116 : 494 - 521. Jump up ^ ( ( Baker, A.J, Haddrath O., Cloutier A, Mcpherson J.D. ( 2014 ). Genomic Support for a Moa - Tinamous Clade and Adaptive Morphological Convergence in Flightless Ratites. Molecular Biology and Evolution ( Internet ). ( July 2014, cited 2014 Oct. 28 ) ) ) Jump up ^ `` New Zealand 's Icon : Flightless ''. Archived from the original on 2007 - 08 - 18. Retrieved 2007 - 08 - 27. Jump up ^ Haddrath, O. and A.J. Baker ( 2012 ). `` Multiple nuclear genes and retroposons support vicariance and dispersal of the palaeognaths, and an Early Cretaceous origin of modern birds. '' Proceedings of the Royal Society B : Biological Sciences : rspb20121630. Jump up ^ Harshman, J., E.L. Braun, M.J. Braun, C.J. Huddleston, R.C. Bowie, J.L. Chojnowski, S.J. Hackett, K. - L. Han, R.T. Kimball and B.D. Marks ( 2008 ). `` Phylogenomic evidence for multiple losses of flight in ratite birds. '' Proceedings of the National Academy of Sciences 105 : 13462 - 7. ^ Jump up to : Smith, J.V., E.L. Braun and R.T. Kimball ( 2012 ). `` Ratite non-monophyly : Independent evidence from 40 novel loci. '' Systematic biology : sys067. Jump up ^ Nudds, R.L. ; Slove Davidson, J. ( 2010 ). `` A shortening of the manus precedes the attenuation of other wing - bone elements in the evolution of flightlessness in birds ''. Acta Zoologica. 91 : 115 -- 122. doi : 10.1111 / j. 1463 - 6395.2009. 00391. x. ^ Jump up to : Baker, A.J., O. Haddrath, J.D. McPherson and A. Cloutier ( 2014 ). `` Genomic support for a moa - tinamou clade and adaptive morphological convergence in flightless ratites. '' Molecular biology and evolution : msu153. ^ Jump up to : McNab, B.K. ( 1994 ). `` Energy conservation and the evolution of flightlessness in birds. '' American Naturalist : 628 - 42. ^ Jump up to : Cubo, J. and W. Arthur ( 2000 ). `` Patterns of correlated character evolution in flightless birds : a phylogenetic approach. '' Evolutionary Ecology 14 : 693 - 702. Jump up ^ Elliott, K. `` High flight costs, but low dive costs, in auks support the biomechanical hypothesis for flighlessness in penguins ''. PNAS. Jump up ^ Roots, Clive. Flightless Birds. Westport, CT : Greenwood, 2006. 136 - 37. Print. Jump up ^ Handford, P. and M.A. Mares ( 1985 ). `` The mating systems of ratites and tinamous : an evolutionary perspective. '' Biological Journal of the Linnean Society 25 : 77 - 104. Jump up ^ Hunter, Laurie A ( 1988 ). `` Status of the Endemic Atitlan Grebe of Guatemala : Is it Extinct ? '' ( pdf ). Condor. 90 ( 4 ) : 906 -- 912. doi : 10.2307 / 1368847. JSTOR 1368847. Retrieved 2007 - 04 - 03. Jump up ^ Diamond, Jared ( 1991 ). `` A new species of rail from the Solomon Islands and convergent evolution of insular flightlessness '' ( PDF ). The Auk. 108 ( 3 ) : 461 -- 470. doi : 10.2307 / 4088088. JSTOR 4088088. Jump up ^ Roots, Clive. Flightless Birds. Westport, CT : Greenwood, 2006. 136 - 37. Print. External links TerraNature pages on New Zealand flightless birds Kiwi in Te Ara -- the Encyclopedia of New Zealand Flightless Birds Retrieved from `` https://en.wikipedia.org/w/index.php?title=Flightless_bird&oldid=827938075 '' Categories : Flightless birds Hidden categories : CS1 maint : Multiple names : authors list Wikipedia articles needing clarification from November 2014 All articles with unsourced statements Articles with unsourced statements from July 2012 Talk Contents About Wikipedia বাংলা Bosanski Català Deutsch Español Esperanto فارسی Français Frysk Galego 한국어 हिन्दी Hrvatski עברית 日本 語 Polski Português Русский Simple English Slovenščina Српски / srpski Srpskohrvatski / српскохрватски தமிழ் Українська Tiếng Việt 中文 17 more Edit links This page was last edited on 27 February 2018, at 16 : 56. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. 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Question: why are birds such as kiwi and penguin unable to fly
Answer: through evolution