Editing Elephant bird (section)

== Taxonomy and biogeography ==
[[File:Mullerornis agilis.jpg|thumb|left|''[[Mullerornis modestus]]'']]
[[File:Aepyornis maximus 01 L.D..jpg|upright|thumb|''Aepyornis maximus'' restoration]]
Like the [[ostrich]], [[Rhea (bird)|rhea]], [[cassowary]], [[emu]], [[Kiwi (bird)|kiwi]] and extinct [[moa]], elephant birds were ratites; they could not fly, and their [[sternum|breast bones]] had no [[keel (bird anatomy)|keel]]. Because Madagascar and [[Africa]] separated before the ratite [[lineage (evolution)|lineage]] arose,<ref>Yoder, A. D. & Nowak, M. D. (2006)</ref> elephant birds are thought to have dispersed and become flightless and gigantic ''[[in situ]]''.<ref>van Tuinen, M. et al. (1998)</ref>

More recently, it has been deduced from DNA sequence comparisons that the closest living relatives of elephant birds are New Zealand [[Kiwi (bird)|kiwi]],<ref name="Mitchell2014">{{Cite journal | doi = 10.1126/science.1251981| pmid = 24855267| title = Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution| journal = Science| volume = 344| issue = 6186| pages = 898–900| date = 2014-05-23| display-authors= 3| last1 = Mitchell | first1 = K. J.| last2 = Llamas | first2 = B.| last3 = Soubrier | first3 = J.| last4 = Rawlence | first4 = N. J.| last5 = Worthy | first5 = T. H.| last6 = Wood | first6 = J.| last7 = Lee | first7 = M. S. Y.| last8 = Cooper | first8 = A.| bibcode = 2014Sci...344..898M| url = https://dspace.flinders.edu.au/xmlui/bitstream/2328/35953/1/Mitchell_AncientDNA_AM2014.pdf| hdl = 2328/35953| s2cid = 206555952| hdl-access = free}}</ref> though the split between the two groups is deep, with the two lineages being estimated to have diverged from each other around 54 million years ago.<ref name=":0" />

Placement of Elephant birds within Palaeognathae, after:<ref>{{Cite journal |last=Takezaki |first=Naoko |date=2023-06-01 |editor-last=Holland |editor-first=Barbara |title=Effect of Different Types of Sequence Data on Palaeognath Phylogeny |journal=Genome Biology and Evolution |language=en |volume=15 |issue=6 |doi=10.1093/gbe/evad092 |issn=1759-6653 |pmc=10262969 |pmid=37227001}}</ref><ref>{{Cite journal |last1=Urantówka |first1=Adam Dawid |last2=Kroczak |first2=Aleksandra |last3=Mackiewicz |first3=Paweł |date=December 2020 |title=New view on the organization and evolution of Palaeognathae mitogenomes poses the question on the ancestral gene rearrangement in Aves |journal=BMC Genomics |language=en |volume=21 |issue=1 |page=874 |doi=10.1186/s12864-020-07284-5 |doi-access=free |issn=1471-2164 |pmc=7720580 |pmid=33287726}}</ref> 

{{clade
|label1=[[Paleognathae]]
|1={{clade
|1=[[Struthionidae]] (ostriches)
|2={{clade
|1=[[Rheidae]] (rheas)
|2={{clade
|1=[[Tinamidae]] (tinamou)
|2={{extinct}}[[Dinornithiformes]] (moa)
}}
|3={{clade
|1=[[Apterygidae]] (kiwis)
|2={{extinct}}'''Aepyornithiformes''' (elephant birds)
}}
|4=[[Casuariiformes]] (emu, cassowary)
}}}}}}

The ancestors of elephant birds are thought to have arrived in Madagascar well after [[Gondwana]] broke apart. The existence of possible flying [[palaeognathae]] in the Miocene such as ''[[Proapteryx]]'' further supports the view that ratites did not diversify in response to [[vicariance]]. Gondwana broke apart in the Cretaceous and their phylogenetic tree does not match the process of [[continental drift]]. Madagascar has a notoriously poor Cenozoic terrestrial fossil record, with essentially no fossils between the end of the Cretaceous ([[Maevarano Formation]]) and the Late Pleistocene.<ref>{{Cite journal|last1=Samonds|first1=Karen E.|last2=Zalmout|first2=Iyad S.|last3=Irwin|first3=Mitchell T. |last4= Krause| first4= David W.|last5=Rogers|first5=Raymond R.|last6=Raharivony|first6=Lydia L.| display-authors= 3| date=2009-12-12|title=Eotheroides lambondrano, new middle Eocene seacow (Mammalia, Sirenia) from the Mahajanga Basin, northwestern Madagascar|journal=Journal of Vertebrate Paleontology|language=en|volume=29|issue=4|pages=1233–1243|doi=10.1671/039.029.0417|bibcode=2009JVPal..29.1233S |s2cid=59466434|issn=0272-4634}}</ref> Complete mitochondrial genomes obtained from elephant birds eggshells suggest that ''Aepyornis'' and ''Mullerornis'' are significantly genetically divergent from each other, with  [[molecular clock]] analyses estimating the split at around 27-30 million years ago, during the [[Oligocene]] epoch.<ref name=":0">{{Cite journal |display-authors= 3| last1= Grealy| first1= Alicia| last2= Phillips| first2= Matthew |last3= Miller| first3= Gifford|last4=Gilbert|first4=M. Thomas P.|last5=Rouillard|first5=Jean-Marie |last6= Lambert |first6= David| last7= Bunce| first7= Michael |last8=Haile|first8=James|date=April 2017|title=Eggshell palaeogenomics: Palaeognath evolutionary history revealed through ancient nuclear and mitochondrial DNA from Madagascan elephant bird (Aepyornis sp.) eggshell|journal=Molecular Phylogenetics and Evolution |language= en |volume=109|pages=151–163|doi=10.1016/j.ympev.2017.01.005|pmid=28089793| bibcode= 2017MolPE.109..151G}}</ref><ref>{{cite journal |last1=Grealy |first1=Alicia |last2=Miller |first2=Gifford H. |last3=Phillips |first3=Matthew J. |last4=Clarke |first4=Simon J. |last5=Fogel |first5=Marilyn |last6=Patalwala |first6=Diana |last7=Rigby |first7=Paul |last8=Hubbard |first8=Alysia |last9=Demarchi |first9=Beatrice |last10=Collins |first10=Matthew |last11=Mackie |first11=Meaghan |last12=Sakalauskaite |first12=Jorune |last13=Stiller |first13=Josefin |last14=Clarke |first14=Julia A. |last15=Legendre |first15=Lucas J. |last16=Douglass |first16=Kristina |last17=Hansford |first17=James |last18=Haile |first18=James |last19=Bunce |first19=Michael |title=Molecular exploration of fossil eggshell uncovers hidden lineage of giant extinct bird |journal=Nature Communications |date=28 February 2023 |volume=14 |issue=1 |page=914 |doi=10.1038/s41467-023-36405-3 |pmid=36854679 |pmc=9974994 |bibcode=2023NatCo..14..914G }}</ref>

=== Species ===
Up to 10 or 11 species in the genus ''Aepyornis'' have been described,{{sfn|Brodkorb|1963}} but the validity of many have been disputed, with numerous authors treating them all in just one species, ''A. maximus''. Up to three species have been described in ''Mullerornis''.<ref name="Davies">Davies, S. J. J. F. (2003)</ref> Recent work has restricted the number of elephant bird species to three, with two in ''Aepyornis'', one in ''Mullerornis''.<ref name="Molecular exploration of fossil eggshell uncovers hidden lineage of giant extinct bird">{{Cite journal |last1=Grealy |first1=Alicia |last2=Miller |first2=Gifford H. |last3=Phillips |first3=Matthew J. |last4=Clarke |first4=Simon J. |last5=Fogel |first5=Marilyn |last6=Patalwala |first6=Diana |last7=Rigby |first7=Paul |last8=Hubbard |first8=Alysia |last9=Demarchi |first9=Beatrice |last10=Collins |first10=Matthew |last11=Mackie |first11=Meaghan |last12=Sakalauskaite |first12=Jorune |last13=Stiller |first13=Josefin |last14=Clarke |first14=Julia A. |last15=Legendre |first15=Lucas J. |date=2023-02-28 |title=Molecular exploration of fossil eggshell uncovers hidden lineage of giant extinct bird |journal=Nature Communications |language=en |volume=14 |issue=1 |pages=914 |doi=10.1038/s41467-023-36405-3 |issn=2041-1723|doi-access=free |pmid=36854679 |pmc=9974994 |bibcode=2023NatCo..14..914G }}</ref> 
* '''Order Aepyornithiformes''' <small>Newton 1884</small> [Aepyornithes <small>Newton 1884</small>]{{sfn|Brodkorb|1963}}
** '''Genus ''[[Aepyornis]]''''' <small>Geoffroy Saint-Hilaire 1850</small><ref>{{cite book |last1=Hume |first1=Julian P. |url=https://books.google.com/books?id=z7RIAkGw0-UC&q=greater+elephant-bird&pg=PA26 |title=Extinct birds |last2=Walters |first2=Michael |publisher=T&AD Poyser |year=2012 |isbn=978-1-4081-5861-6 |pages=544}}</ref> (Synonym: ''Vorombe'' <small>Hansford & Turvey 2018</small>)
*** ''Aepyornis hildebrandti'' <small>[[Carlos Burckhardt|Burckhardt]], 1893</small> (Possibly divided into two subspecies<ref name="Molecular exploration of fossil eggshell uncovers hidden lineage of giant extinct bird" />) 
*** ''Aepyornis maximus'' <small>[[Isidore Geoffroy Saint-Hilaire|Hilaire]], 1851</small> 
** '''Genus ''[[Mullerornis]]''''' <small>Milne-Edwards & Grandidier 189</small>4
*** ''Mullerornis modestus'' <small>(Milne-Edwards & Grandidier 1869) Hansford & Turvey 2018</small>
All elephant birds are usually placed in the single family Aepyornithidae, but some authors suggest ''Aepyornis'' and ''Mullerornis'' should be placed in separate families within the Aepyornithiformes, with the latter placed into Mullerornithidae.<ref name="Molecular exploration of fossil eggshell uncovers hidden lineage of giant extinct bird" />