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{{short description|Polyphyletic group of birds}}
{{Paraphyletic group
| name = Ratites
| fossil_range = [[Paleocene]]–[[Holocene]] {{fossil range|56|0|earliest=70}} <small>Possible [[Late Cretaceous]] record</small>
| image = Ratite Diversity.jpg
| image_upright = 1.2
| image_caption = Members of the four genera of large extant ratites. Clockwise from top left: [[greater rhea]], [[ostrich]], [[southern cassowary]] and [[emu]]
| auto = yes
| parent = Palaeognathae
| includes = {{ubl|[[Struthioniformes]] <small>(ostriches)</small>|
[[Rheiformes]] <small>(rheas)</small>|[[Casuariiformes]] <small>(cassowaries and emus)</small>|†[[Aepyornithiformes]] <small>(elephant birds)</small>|†[[Dinornithiformes]] <small>(moa)</small>|[[Apterygiformes]] <small>(kiwis)</small>}}
| excludes = * [[Tinamiformes]]
* †[[Lithornithiformes]]
| synonyms = {{ubl|Grallae <small>[[Carl Linnaeus|Linnaeus]], 1760</small><ref name="Gray" />
|Nudipedes <small>[[Jacob Christian Schäffer|Schäffer]], 1774</small><ref name="Gray" />
|Fissipedes bidactyles <small>[[Jacob Christian Schäffer|Schäffer]], 1774</small><ref name="Gray" />
|Retipedes <small>[[Giovanni Antonio Scopoli|Scopoli]], 1777</small><ref name="Gray" />
|Struthiones <small>[[John Latham (ornithologist)|Latham]], 1790</small><ref name="Gray" /><ref name="Salvadori" />
|Campestres <small>[[Johann Karl Wilhelm Illiger|Illiger]], 1811</small><ref name="Gray" />
|Cursores <small>[[Johann Karl Wilhelm Illiger|Illiger]], 1811</small><ref name="Salvadori" />
|Proceri <small>[[Johann Karl Wilhelm Illiger|Illiger]], 1811</small><ref name="Gray" /><ref name="Salvadori" />
|Megistanes <small>[[Louis Pierre Vieillot|Vieillot]], 1816</small><ref name="Gray" /><ref name="Salvadori" />
|Brevipennes <small>[[Georges Cuvier|Cuvier]], 1817</small><ref name="Salvadori" />
|Pressirostres <small>[[Georges Cuvier|Cuvier]], 1817</small><ref name="Gray" />
|Inertes <small>[[Coenraad Jacob Temminck|Temminck]], 1820</small><ref name="Gray" />
|Ratitae <small>[[Camillo Ranzani|Ranzani]], 1823</small><ref name="Gray" />
|Rasores <small>[[Nicholas Aylward Vigors|Vigors]], 1826</small><ref name="Gray" />
|Cursitrices <small>[[William MacGillivray|MacGillivray]], 1840</small><ref name="Gray" />
|Grallatores <small>[[Alexander Keyserling|Keyserling]] & [[Bl(Ornithologist)|Bl.]], 1840</small><ref name="Gray" />
|Proceres <small>[[Sunder.]], 1872</small><ref name="Salvadori" />
|Struthiornithiformes <small>[[John Latham (ornithologist)|Latham]], 1790</small>}}
}}

'''Ratites''' ({{IPAc-en|ˈ|ɹ|æ|t|aɪ|t|s}}) are a [[polyphyletic]] group consisting of all [[bird]]s within the infraclass [[Palaeognathae]] that lack [[keel (bird anatomy)|keel]]s and [[flightless bird|cannot fly]].<ref name="ITIS" /> They are mostly large, long-necked, and long-legged, the exception being the [[Kiwi (bird)|kiwi]], which is also the only [[nocturnal]] extant ratite.

The understanding of relationships within the paleognath clade has been in flux. Previously, all the flightless members had been assigned to the order [[Struthioniformes]], which is more recently regarded as containing only the [[ostrich]].<ref name="Brands" /><ref name = TOLweb /> The modern bird infraclass Palaeognathae consists of ratites and the [[Flying and gliding animals|flighted]] [[Neotropic]] [[tinamou]]s (compare to [[Neognathae]]).<ref name="Phillips2010" /> Unlike other flightless birds, the ratites have no [[keel (bird)|keel]] on their [[sternum]]—hence the name, from the Latin {{lang|la|ratis}} ('[[raft]]', a vessel which has no keel—in contradistinction to extant flighted birds with a keel).<ref name="Fowler"/> Without this to anchor their wing muscles, they could not have flown even if they had developed suitable wings.{{citation needed|reason=Archaeopteryx had no keel but could still fly so this factoid needs a citation|date=June 2015}} Ratites are a [[polyphyletic]] group; tinamous fall within them, and are the [[sister group]] of the extinct [[moa]].<ref name="Phillips2010" /><ref name="Allentoft2012" /><ref name="Mitchell2014" /><ref name="Baker2014"/> This implies that flightlessness is a trait that evolved independently multiple times in different ratite lineages.<ref name="Mitchell2014" /><ref name="Sackton"/>

Most parts of the former [[supercontinent]] [[Gondwana]] have ratites, or did have until the fairly recent past.<ref name="Haddrath, O & Baker, A (2001)" /><ref name="Cooper" /> So did Europe in the [[Paleocene]] and [[Eocene]], from where the first flightless paleognaths are known.<ref name="Buffetaut2014"/> Ostriches were present in Asia as recently as the [[Holocene]], although the genus is thought to have originated in Africa.<ref name="Hou2014"/> However, the ostrich order may have evolved in Eurasia.<ref name="Hou2014"/> A recent study posits a [[Laurasia]]n origin for the clade.<ref name="Yonezawa2017"/> [[Geranoidid]]s, which may have been ratites, existed in North America.<ref name= "Mayr2019"/>

== Species ==
{{See also|List of ratites}}

=== Living forms ===
The African [[ostrich]] is the largest living ratite. A large member of this species can be nearly {{convert|2.8|m|ftin}} tall, weigh as much as {{convert|156|kg|lb}},<ref name = Grzimelek /> and can outrun a horse.

Of the living species, the Australian [[emu]] is next in height, reaching up to {{convert|1.9|m|ftin}} tall and about {{convert|50|kg|lb}}.<ref name = Grzimelek /> Like the ostrich, it is a fast-running, powerful bird of the open plains and [[woodland]]s.

Also native to Australia and the islands to the north are the three species of [[cassowary]]. Shorter than an emu, but heavier and solidly built, cassowaries prefer thickly vegetated [[tropical]] forest. They can be dangerous when surprised or cornered because of their razor-sharp [[Talon (anatomy)|talons]]. In [[New Guinea]], cassowary eggs are brought back to villages and the chicks raised for eating as a much-prized delicacy, despite (or perhaps because of) the risk they pose to life and limb. They reach up to {{convert|1.8|m|ftin}} tall and weigh as much as {{convert|85|kg|lb}}<ref name = Grzimelek />

[[South America]] has two species of [[Rhea (bird)|rhea]], large fast-running birds of the [[Pampas]]. The larger [[American rhea]] grows to about {{convert|1.4|m|ftin}} tall and usually weighs {{convert|15|to(-)|40|kg|lb}}.<ref name = Grzimelek />

The smallest ratites are the five species of [[Kiwi (bird)|kiwi]] from New Zealand. Kiwi are [[chicken]]-sized, shy, and [[nocturnal]]. They nest in deep [[burrow]]s and use a highly developed sense of smell to find small insects and grubs in the soil. Kiwi are notable for laying eggs that are very large in relation to their body size. A kiwi egg may equal 15 to 20 percent of the body mass of a female kiwi. The smallest species of kiwi is the [[little spotted kiwi]], at {{convert|0.9|to(-)|1.9|kg|lb}} and {{convert|35|to(-)|45|cm|in}}.<ref name = Grzimelek />

=== Holocene extinct forms ===
At least nine species of [[moa]] lived in New Zealand before the arrival of humans, ranging from turkey-sized to the [[giant moa]] ''[[Dinornis robustus]]'' with a height of {{convert|3.7|m|ftin}} and weighing about {{convert|230|kg|lb}}.<ref name = Grzimelek /> They became extinct by A.D. 1400 due to hunting by [[Māori people|Māori]] settlers, who arrived around A.D. 1280.

''[[Aepyornis maximus]]'', the "elephant bird" of [[Madagascar]], was the heaviest bird ever known. Although shorter than the tallest moa, a large ''A. maximus'' could weigh over {{convert|400|kg|lb}} and stand up to {{convert|3|m|ftin}} tall.<ref name = Grzimelek /> Accompanying it were three other species of ''[[Aepyornis]]'' as well as three species of the smaller genus ''[[Mullerornis]]''. All these species went into decline following the arrival of humans on Madagascar around 2,000 years ago, and were gone by the 17th or 18th century if not earlier.

== Classification ==<!-- AnAcadCiêncBras74:365; CanJZool81:962 -->
[[File:Kiwi, ostrich, Dinornis.jpg|thumb|Comparison of a [[Kiwi (bird)|kiwi]], [[ostrich]], and ''[[Dinornis]]'', each with its egg]]

There are two [[Taxonomy (biology)|taxonomic]] approaches to ratite classification: one combines the groups as [[family (biology)|families]] in the [[order (biology)|order]] '''Struthioniformes''', while the other supposes that the lineages evolved mostly independently and thus elevates the families to order rank ('''Rheiformes''', '''Casuariformes''' etc.).

== Evolution ==

The longstanding story of ratite evolution was that they share a common flightless ancestor that lived in [[Gondwana]], whose descendants were isolated from each other by [[continental drift]], which carried them to their present locations. Supporting this idea, some studies based on morphology, immunology and DNA sequencing reported that ratites are [[monophyletic]].<ref name ="Haddrath, O & Baker, A (2001)"/><ref>{{Cite journal |last=Roff |first=Derek A. |year=1994 |title=The evolution of flightlessness: Is history important? |url=http://link.springer.com/10.1007/BF01237847 |journal=[[Evolutionary Ecology]] |lang=en |volume=8 |issue=6 |pages=639–657 |doi=10.1007/BF01237847 |bibcode=1994EvEco...8..639R |s2cid=13524994 |issn=0269-7653|url-access=subscription }}</ref> Cracraft's 1974 biogeographic vicariance hypothesis suggested that ancestral flightless paleognaths, the ancestors of ratites, were present and widespread in Gondwana during the Late Cretaceous. As the supercontinent fragmented due to [[plate tectonics]], they were carried by plate movements to their current positions and evolved into the species present today.<ref name=Cracraft/> The earliest known ratite fossils date to the [[Paleocene]] epoch about 56 million years ago (e.g., ''[[Diogenornis]]'', a possible early relative of the rhea).<ref name = Laurinetal2012 /> However, more primitive [[paleognathae|paleognaths]] are known from several million years earlier,<ref name = Leonardetal2005 /> and the classification and membership of the Ratitae itself is uncertain. Some of the earliest ratites occur in Europe.<ref name=Buffetaut2014/>

Recent analyses of genetic variation between the ratites do not support this simple picture. The ratites may have diverged from one another too recently to share a common Gondwanan ancestor. Also, the Middle Eocene ratites such as ''[[Palaeotis]]'' and ''[[Remiornis]]'' from Central Europe may imply that the "out-of-Gondwana" hypothesis is oversimplified.

Molecular phylogenies of the ratites have generally placed ostriches in the [[Basal (phylogenetics)|basal]] position and among extant ratites, placed rheas in the second most basal position, with Australo-Pacific ratites splitting up last; they have also shown that both the latter groups are monophyletic.<ref name = "Harshman" /><ref name = "Mitchell2014" /><ref name = Baker2014/> Early mitochondrial genetic studies that failed to make ostriches basal<ref name = "Haddrath, O & Baker, A (2001)"/><ref name = Cooper/> were apparently compromised by the combination of rapid early radiation of the group and long terminal branches.<ref name = Baker2014/> A morphological analysis that created a basal New Zealand clade<ref name = Bourdon/> has not been corroborated by molecular studies. A 2008 study of nuclear genes shows ostriches branching first, followed by rheas and tinamous, then kiwi splitting from emus and cassowaries.<ref name = Harshman/> In more recent studies, moas and tinamous were shown to be [[sister group]]s,<ref name = Phillips2010/><ref name = Allentoft2012/><ref name = Baker2014/>  and elephant birds were shown to be most closely related to the New Zealand kiwi.<ref name = Mitchell2014/> Additional support for the latter relationship was obtained from morphological analysis.<ref name = Mitchell2014/>

The finding that tinamous nest within this group, originally based on twenty nuclear genes<ref name = "Harshman" /> and corroborated by a study using forty novel nuclear loci<ref name = Smith2013/> makes 'ratites' [[Polyphyly|polyphyletic]] rather than monophyletic, if we exclude the tinamous.<ref name = Hackett/><ref name=Sackton/> Since tinamous are weak fliers, this raises interesting questions about the evolution of flightlessness in this group. The branching of the tinamous within the ratite radiation suggests flightlessness [[parallel evolution|evolved independently]] among ratites at least three times.<ref name =Harshman/><ref name = Holmes/><ref name=Sackton/> More recent evidence suggests this happened at least six times, or once in each major ratite lineage.<ref name = "Mitchell2014" /><ref name="Sackton"/> Re-evolution of flight in the tinamous would be an alternative explanation, but such a development is without precedent in avian history, while loss of flight is commonplace.<ref name = Harshman/><ref name="Sackton"/>

{{cladogram
|title= [[Cladogram]] based on Mitchell ''et al.'' (2014)<ref name = Mitchell2014/><br/> and Yonezawa ''et al.'' (2016)<ref name=Yonezawa2017/>
|clades={{Clade
   |style=width:35em;
   |label1=recent [[paleognath]]s
   |1={{Clade
       |1={{clade
          |label1=
          |1=[[Struthionidae]] (ostriches, 2&nbsp;spp.)
          }}
       |label2=
       |2={{Clade
          |1={{clade
               |label1=
               |1=[[Rheidae]] (rheas, 2~3&nbsp;spp.)
               }}
          |label2=
          |2={{Clade
             |1={{clade
                |label1=
                |1={{Clade
                   |label1=
                   |1=†[[Dinornithiformes]] (moa)
                   |2=[[Tinamidae]] (tinamous, 46&nbsp;spp.)
                   }}
                }}
             |label2=
             |2={{Clade
                |label1=
                |1={{Clade
                   |label1=
                   |1=†[[Aepyornithidae]] (elephant birds)
                   |2=[[Apterygidae]] (kiwi, 5&nbsp;spp.)
                   }}
                   |2={{Clade
                      |label1=
                      |1=[[Casuariidae]] (cassowaries, 3&nbsp;spp.)
                      |2=[[Dromaiidae]] (emus, 1&nbsp;sp.)
                      }}
                }}
            }}

            }}

        }}
     }}
 }}

By 2014, a mitochondrial DNA phylogeny including fossil members placed ostriches on the [[Basal (phylogenetics)|basal]] branch, followed by rheas, then a clade consisting of moas and tinamous, followed by the final two branches: a clade of emus plus cassowaries and one of elephant birds plus kiwis.<ref name = Mitchell2014/>

[[vicariance|Vicariant speciation]] based on the [[plate tectonics|plate tectonic]] split-up of Gondwana followed by continental drift would predict that the deepest phylogenetic split would be between African and all other ratites, followed by a split between South American and Australo-Pacific ratites, roughly as observed. However, the elephant bird–kiwi relation appears to require dispersal across oceans by flight,<ref name = Mitchell2014/> as apparently does the colonization of New Zealand by the moa and possibly the back-dispersal of tinamous to South America, if the latter occurred.<ref name = Phillips2010/> The phylogeny as a whole suggests not only multiple independent origins of flightlessness, but also of gigantism (at least five times).<ref name = "Mitchell2014" /> [[Cope's rule|Gigantism]] in birds tends to be [[Island gigantism|insular]]; however, a ten-million-year-long window of opportunity for evolution of avian gigantism on continents may have existed following the [[Cretaceous–Paleogene extinction event|extinction of the non-avian dinosaurs]], in which ratites were able to fill vacant herbivorous niches before mammals attained large size.<ref name = Mitchell2014/> Some authorities, though, have been skeptical of the new findings and conclusions.<ref name = Zimmer2014/>

Kiwi and tinamous are the only palaeognath lineages not to evolve gigantism, perhaps because of competitive exclusion by giant ratites already present on New Zealand and South America when they arrived or arose.<ref name = "Mitchell2014" /> The fact that New Zealand has been the only land mass to recently support two major lineages of flightless ratites may reflect the near total absence of native mammals, which allowed kiwi to occupy a mammal-like nocturnal [[Ecological niche|niche]].<ref name="Le DucRenaud2015"/> However, various other landmasses such as South America and Europe have supported multiple lineages of flightless ratites that evolved independently, undermining this competitive exclusion hypothesis.<ref name=Agnolin2016/>

Most recently, studies on genetic and morphological divergence and fossil distribution show that paleognaths as a whole probably had an origin in the northern hemisphere. Early Cenozoic northern hemisphere paleognaths such as ''[[Lithornis]]'', ''[[Pseudocrypturus]]'', ''[[Paracathartes]]'' and ''[[Palaeotis]]'' appear to be the most basal members of the clade.<ref name=Yonezawa2017/> The various ratite lineages were probably descended from flying ancestors that independently colonised South America and Africa from the north, probably initially in South America. From South America, they could have traveled overland to Australia via Antarctica,<ref name = Tambussi1994/> (by the same route marsupials are thought to have used to reach Australia<ref name = Nilsson2010/>) and then reached New Zealand and Madagascar via "sweepstakes" dispersals (rare low probability dispersal methods, such as long distance rafting) across the oceans. Gigantism would have evolved subsequent to trans-oceanic dispersals.<ref name=Yonezawa2017/>

===Loss of flight===

Loss of flight allows birds to eliminate the costs of maintaining various flight-enabling adaptations like high [[Bird anatomy#Muscular system|pectoral muscle]] mass, hollow bones and a light build, et cetera.<ref name = Mcnab1994 /> The basal metabolic rate of flighted species is much higher than that of flightless terrestrial birds.<ref name="Cubo"/> But energetic efficiency can only help explain the loss of flight when the benefits of flying are not critical to survival.

Research on flightless rails indicates the flightless condition evolved in the absence of predators.<ref name=Mcnab2006/> This shows flight to be generally necessary for survival and dispersal in birds.<ref name=Diamond1991/> In apparent contradiction to this, many landmasses occupied by ratites are also inhabited by predatory mammals.<ref name=Mitchell2014/> However, the [[K–Pg extinction event]] created a window of time with large predators absent that may have allowed the ancestors of extant flightless ratites to evolve flightlessness. They subsequently underwent selection for large size.<ref name=Phillips2010/> One hypothesis suggests that as predation pressure decreases on islands with low raptor species richness and no mammalian predators, the need for large, powerful flight muscles that make for a quick escape decreases. Moreover, raptor species tend to become generalist predators on islands with low species richness, as opposed to specializing in the predation of birds. An increase in leg size compensates for a reduction in wing length in insular birds that have not lost flight by providing a longer lever to increase force generated during the thrust that initiates takeoff.<ref name = Wright2016/>

== Description ==
Ratites in general have many physical characteristics in common, although many are not shared by the family [[Tinamidae]], or tinamous. First, the [[pectoralis major muscle|breast muscles]] are underdeveloped. They do not have keeled [[sternum|sterna]]. Their wishbones ([[furcula]]e) are almost absent. They have simplified wing skeletons and musculature. Their legs are stronger and do not have air chambers, except the [[femur]]s. Their tail and flight feathers have retrogressed or have become decorative plumes. They have no feather vanes, which means they do not need to oil their feathers, hence they have no [[preen gland]]s. They have no separation of pterylae (feathered areas) and apteria (non-feathered areas),<ref>http://www.freedictionary.com for definitions of the two latin words</ref> and finally, they have [[palaeognath]]ous [[palate]]s.<ref name = Bruning />

Ostriches have the greatest [[Sexual dimorphism|dimorphism]]; rheas show some [[dichromatism]] during the breeding season. Emus, cassowaries, and kiwis show some dimorphism, predominantly in size.

While the ratites share a lot of similarities, they also have major differences. Ostriches have only two toes, with one being much larger than the other. Cassowaries have developed long inner toenails, used defensively. Ostriches and rheas have prominent wings; although they do not use them to fly, they do use them in courtship and predator distraction.<ref name = "Bruning" />

Without exception, ratite chicks are capable of swimming and even diving.{{citation needed|date=November 2013}}

On an [[allometric]] basis, [[paleognath]]s have generally smaller brains than [[neognath]]s. Kiwis are exceptions to this trend, and possess proportionally larger brains comparable to those of [[parrots]] and [[songbirds]], though evidence for similar advanced cognitive skills is currently lacking.<ref name="Corfield2007"/>

=== Gallery of living species ===
<gallery>
Image:Autruche Thoiry 19801.jpg|[[Ostrich]]
Image:Masai Ostriches Benh.jpg|Ostrich herd (''S. camelus massaicus'')
Image:Rhea side profile.jpg|[[American rhea]]
Image:Darwin-Nandus.jpg|[[Darwin's rhea]]
Image:Double-wattled Cassowary.jpg|[[Southern cassowary]]
File:Casuarius unappendiculatus -Northern Cassowary -head to toe.jpg|[[Northern cassowary]]
Image:Mooruk-Wolf.jpg|[[Dwarf cassowary]]
File:Dromaius novaehollandiae qtl1.jpg|[[Emu]]
Image:Apteryx haastii.jpg|[[Great spotted kiwi]]
Image:Apteryx owenii 0.jpg|[[Little spotted kiwi]]
<!-- Image:Kkr.jpg|[[Okarito Brown Kiwi]] -->

Image:Kiwifugl.jpg|[[North Island brown kiwi]]
</gallery>

== Behavior and ecology ==

=== Feeding and diet ===
Ratite chicks tend to be more [[omnivorous]] or [[insectivorous]]; similarities in adults end with feeding, as they all vary in diet and length of digestive tract, which is indicative of diet. Ostriches, with the longest tracts at {{convert|14|m|ft|abbr=on}}, are primarily [[herbivorous]]. Rheas' tracts are next longest at {{convert|8|-|9|m|ft|abbr=on}}, and they also have [[caecum|caeca]]. They are also mainly [[herbivores]], concentrating on broad-leafed plants. However, they will eat insects if the opportunity arises. Emus have tracts of {{convert|7|m|ft|abbr=on}} length, and have a more omnivorous diet, including insects and other small animals. Cassowaries have next to the shortest tracts at {{convert|4|m|ft|abbr=on}}. Finally, kiwi have the shortest tracts and eat earthworms, insects, and other similar creatures.<ref name = "Bruning" /> [[Moas]] and [[elephant birds]] were the largest native herbivores in their faunas, far larger than contemporary herbivorous mammals in the latter's case.<ref name="Buffetaut2014" />

Some extinct ratites might have had odder lifestyles, such as the narrow-billed ''[[Diogenornis]]'' and ''[[Palaeotis]]'', compared to the shorebird-like [[lithornithids]], and could imply similar animalivorous diets.<ref name="Alvarenga"/><ref>{{cite book |last1=Mayr |first1=Gerald |title=Paleogene Fossil Birds |date=2009 |publisher=Springer Science & Business Media |isbn=978-3-540-89628-9 |doi=10.1007/978-3-540-89628-9 }}{{pn|date=January 2022}}</ref>

=== Reproduction ===
Ratites are different from the flying birds in that they needed to adapt or evolve certain features to protect their young. First and foremost is the thickness of the shells of their eggs. Their young are hatched more developed than most and they can run or walk soon thereafter. Also, most ratites have communal nests, where they share the incubating duties with others. Ostriches, and great spotted kiwis, are the only ratites where the female incubates; they share the duties, with the males incubating at night.  Cassowaries and emu are polyandrous, with males incubating eggs and rearing chicks with no obvious contribution from females. Ostriches and rheas are polygynous with each male courting several females. Male rheas are responsible for building nests and incubating while ostrich males incubate only at night. Kiwis stand out as the exception with extended monogamous reproductive strategies where either the male alone or both sexes incubate a single egg.<ref name = "Bruning" /> Unlike most birds, male ratites have a [[Intromittent organ#Birds|phallus]] that is inserted into the female's [[cloaca]] during [[copulation (zoology)|copulation]].<ref>{{Cite book |last1=Farner |first1=Donald S. |url=https://books.google.com/books?id=LS3LBAAAQBAJ&pg=PA68 |title=Avian Biology: Volume III |last2=King |first2=James R. |date=2013-09-03 |publisher=Elsevier |isbn=978-1-4832-6943-6 |language=en}}</ref>

== Ratites and humans ==
Ratites and humans have had a long relationship starting with the use of the egg for water containers, jewelry, or other art medium. Male ostrich feathers were popular for hats during the 18th century, which led to hunting and sharp declines in populations. Ostrich farming grew out of this need, and humans harvested feathers, hides, eggs, and meat from the ostrich. Emu farming also became popular for similar reasons and for their [[emu oil]]. Rhea feathers are popular for dusters, and eggs and meat are used for chicken and pet feed in South America. Ratite hides are popular for leather products like shoes.<ref name = "Bruning" />

=== United States regulation ===
The USDA's [[Food Safety and Inspection Service]] (FSIS) began a voluntary, fee-for-service ratite inspection program in 1995 to help the fledgling industry improve the marketability of the meat. A provision in the FY2001 USDA appropriations act (P.L. 106–387) amended the [[Poultry Products Inspection Act]] to make federal inspection of ratite meat mandatory as of April 2001 (21 U.S.C. 451 et seq.).<ref name = "Womach2005" />

== See also ==
*[[List of Struthioniformes by population]]

== References ==
{{Reflist
| colwidth = 30em
| refs =

<ref name="Agnolin2016">{{cite journal|last1= Agnolin|first1=F. L.|title= Unexpected diversity of ratites (Aves, Palaeognathae) in the early Cenozoic of South America: palaeobiogeographical implications|journal=Alcheringa: An Australasian Journal of Palaeontology|volume=41|date= 2016-07-05|issue=1 |pages= 101–111|doi= 10.1080/03115518.2016.1184898|bibcode=2017Alch...41..101A |s2cid=132516050}}</ref>

<ref name = "Allentoft2012">{{Cite journal | doi = 10.1016/j.aanat.2011.04.002| pmid = 21596537| title = Moa's Ark or volant ghosts of Gondwana? Insights from nineteen years of ancient DNA research on the extinct moa (Aves: Dinornithiformes) of New Zealand| journal = Annals of Anatomy - Anatomischer Anzeiger| volume = 194| issue = 1| pages = 36–51| date = 2012-01-20| last1 = Allentoft | first1 = M. E. | last2 = Rawlence | first2 = N. J. | url = http://researchrepository.murdoch.edu.au/id/eprint/4368/1/Moa%27s_ark_or_volant_ghosts.pdf}}</ref>

<ref name="Alvarenga">{{cite journal |last=Alvarenga |first=H. M. F. |year=1983 |title=Uma ave ratitae do Paleoceno Brasileiro: bacia calcária de Itaboraí, Estado do Rio de Janeiro, Brasil |journal=Boletim do Museu Nacional (Rio de Janeiro), Geologia |series=Nova Série |volume=41 |pages=1–8}}</ref>

<ref name = "Baker2014">{{Cite journal | doi = 10.1093/molbev/msu153| title = Genomic Support for a Moa-Tinamou Clade and Adaptive Morphological Convergence in Flightless Ratites| journal = Molecular Biology and Evolution| year = 2014| last1 = Baker | first1 = A. J.| last2 = Haddrath | first2 = O.| last3 = McPherson | first3 = J. D.| last4 = Cloutier | first4 = A.| volume=31 | issue = 7| pages=1686–1696 | pmid=24825849| doi-access = free}}</ref>

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}}

== External links ==
{{Commons category|Palaeognathae}}
{{Americana Poster|Ratitæ}}
* [http://www.dmoz.org/Science/Agriculture/Animals/Birds/Ratites/ Websites With Information On Ratites]

{{Taxonbar|from=Q19170}}

[[Category:Ratites| ]]
[[Category:Flightless birds]]
[[Category:Extant Thanetian first appearances]]
[[Category:Taxa named by William Plane Pycraft]]
[[Category:Polyphyletic groups]]