Editing Megatherium (section)

== Research history ==
[[File:MegatheriumSqueletteCuvier1812.jpg|thumb|Illustration of the first specimen of ''Megatherium americanum'' from 1796|left]]
[[File:La terre avant le déluge, 1863 "Mégathérium restauré". (4513818527).jpg|thumb|Life illustration of ''Megatherium americanum'' from 1863, depicting it with a short trunk|left]]
The earliest specimen of ''Megatherium americanum'' was discovered in 1787 by Manuel de Torres, a [[Dominican Order|Dominican]] friar and naturalist, from a ravine on the banks of the [[Luján River|Lujan River]] in what is now northern Argentina, which at the time was part of the [[Viceroyalty of the Río de la Plata]] in the [[Spanish Empire]]. Torres described the bones as a ‘wonder and providence of the Lord’. On the orders of the then viceroy of la Plata, [[Nicolás del Campo|Nicolás Cristóbal del Campo, Marqués de Loreto]], the specimen was moved to the capital [[Buenos Aires]]. There the skeleton was drawn for the first time by [[:es:José Custodio de Sáa y Faría|José Custodio Sáa y Faria]] in a horse-like posture. Campo summoned a number of local indigenous leaders to ask if they had heard of the animal. The skeleton was then transferred by Campo to the Royal Cabinet of Natural History of Madrid (now the [[Museo Nacional de Ciencias Naturales|National Museum of Natural Sciences]] MNCN) in 7 crates, which had arrived and been unpacked by late 1788.<ref name=":0">{{Citation |last=Pimentel |first=Juan |title=Megatherium |date=2021 |work=New World Objects of Knowledge |pages=231–236 |editor-last=Pimentel |editor-first=Juan |url=https://www.jstor.org/stable/j.ctv1vbd275.38 |access-date=2024-04-23 |series=A Cabinet of Curiosities |publisher=University of London Press |jstor=j.ctv1vbd275.38 |isbn=978-1-908857-82-8 |editor2-last=Thurner |editor2-first=Mark}}</ref>

At the direction of the cabinets main taxidermist Juan Bautista Bru, the specimen was then mounted for public exhibition (which remains unaltered in the modern museum display). In 1796 a scientific description of the skeleton was published authored by Bru along with engineer Joseph Garriga, with engravings by Manuel Navarro. As the work was going through the process of publication in 1795, preliminary prints of the paper were obtained by French diplomat Philippe-Rose Roume who was in Madrid at the time, who sent them to the [[National Museum of Natural History, France|National Museum of Natural History]] (''Muséum national d'histoire naturelle'') in Paris, France, where they were seen by French anatomist and paleontologist [[Georges Cuvier]].<ref name=":0" />

Cuvier, working solely from the prints from Madrid and not visiting the specimen personally,<ref name=":0" /> and using [[comparative anatomy]] with "edentate" mammals (now recognised as members of the order [[Xenarthra]]) in the collection of the Paris museum,<ref name=":2">{{Citation |last=Argot |first=Christine |title=Changing Views in Paleontology: The Story of a Giant (Megatherium, Xenarthra) |date=2008 |work=Mammalian Evolutionary Morphology |series=Vertebrate Paleobiology and Paleoanthropology Series |pages=37–50 |editor-last=Sargis |editor-first=Eric J. |url=http://link.springer.com/10.1007/978-1-4020-6997-0_3 |access-date=2024-04-23 |place=Dordrecht |publisher=Springer Netherlands |language=en |doi=10.1007/978-1-4020-6997-0_3 |isbn=978-1-4020-6996-3 |editor2-last=Dagosto |editor2-first=Marian}}</ref> correctly recognised that the remains represented those of a giant sloth, and an animal that was entirely extinct and not living. In early 1796, somewhat before the full publication of the work by Bru, Garriga and Navarro, Cuvier published a paper naming the species ''Megatherium americanum'' (literally "Great American beast"),<ref name=":0" /> becoming the first fossil mammal to be identified with both a [[genus]] and species name. Which description had [[Principle of priority|priority]] has been controversial in the past. Cuvier later wrote a fuller description in 1804, which was republished in his famous 1812 book ''Recherches sur les ossemens fossiles de quadrupèdes.'' Cuvier identified ''Megatherium'' as a sloth primarily on the basis of its skull morphology, the [[dental formula]] and the shoulder, while regarding the anatomy of its limbs as more similar to [[armadillo]]s and [[anteater]]s. Cuvier suggested that based on the proportions of its limbs (which are approximately equal to each other), that ''Megatherium'' did not jump or run, nor crawl like living sloths, with the presence of a [[clavicle]] and well developed crests on the [[humerus]], suggesting to Cuvier that the animal probably used its forelimbs to grasp.<ref name=":2" /> A later publication in 1823 by Cuvier suggested that giant carapaces found in the Pampas also belonged to ''Megatherium'', but British paleontologist [[Richard Owen]] in 1839 demonstrated that these actually belonged to another extinct group of xenarthrans called [[glyptodonts]] that were related to armadillos.<ref name=":1">Fernicola, J. C., Vizcaino, S. F., & De Iuliis, G. (2009). The fossil mammals collected by Charles Darwin in South America during his travels on board the HMS Beagle. ''Revista De La Asociación Geológica Argentina'', ''64''(1), 147–159. Retrieved from <nowiki>https://revista.geologica.org.ar/raga/article/view/1339</nowiki></ref>

Additional remains of ''Megatherium'' were collected by [[Charles Darwin]] during the [[Second voyage of HMS Beagle|Voyage of the Beagle]] in the 1830s, these remains were assigned by Richard Owen in 1840 to the species ''Megatherium cuvieri'', which had been named by [[Anselme Gaëtan Desmarest]] in 1822. These remains are now assigned to ''M. americanum.''<ref name=":1" />[[File:Megatherium Crystal Palace.jpg|thumb|left|19th century ''M. americanum'' sculpture in [[Crystal Palace Park]], London, England|200x200px]]Owen later wrote a monograph series from 1851 to 1860 thoroughly describing the anatomy of ''M. americanum.''<ref>Owen R (1851) On the ''Megatherium'' (''Megatherium americanum'', Blumenbach). Part I. Preliminary observations on the exogenous processes of vertebrae. Phil Trans R Soc Lond 141:719–764</ref><ref>Owen R (1855) On the ''Megatherium'' (''Megatherium americanum'', Cuvier and Blumenbach). Part II. Vertebrae of the trunk. Phil Trans R Soc Lond 145:359–388</ref><ref>Owen R (1856) On the ''Megatherium'' (''Megatherium americanum'', Cuvier and Blumenbach). Part III. The skull. Phil Trans R Soc Lond 146:571–589</ref><ref>Owen R (1858) On the ''Megatherium'' (''Megatherium americanum'', Cuvier and Blumenbach). Part IV. Bones of the anterior extremities. Phil Trans R Soc Lond 148:261–278</ref><ref>Owen R (1859) On the ''Megatherium'' (''Megatherium americanum'', Cuvier and Blumenbach). Part V. Bones of the posterior extremities. Phil Trans R Soc Lon149:809–829</ref><ref>Owen R (1861) Memoir on the ''Megatherium'', or Giant Ground-sloth of America (''Megatherium americanum'', Cuvier). Williams and Norgate, London</ref>

From the late 19th century onward additional species of ''Megatherium'' were described. In 1888 Argentine explorer [[Francisco Moreno]] erected the species ''Megatherium filholi''  for remains found in the Late Pleistocene of Argentina.<ref>Moreno, F.P. (1888): Informe preliminar de los progresos del Museo La Plata durante el primer semestre de 1888. – Boletín del Museo La Plata, 1: 1-35.</ref><ref name=":14" />''<ref name=":9" />'' In 1880 [[Paul Gervais]] and [[Florentino Ameghino]] described the species ''M. tarijense'' from remains of Pleistocene age found in Bolivia. In 1893 [[Rodolfo Amando Philippi]] erected the species ''M. sundti'' and ''M. medinae'' from remains found in the Pleistocene of Bolivia and Chile, respectively.<ref>Philippi, R.A. 1893a. Vorläufige Nachricht über fossile Säugethierknochen von Ulloma, Bolivia. Zeitschrift der deutschen geologischen Gesellschaft 45: 87–96.</ref><ref>Philippi, R.A. 1893b. Noticias preliminares sobre huesos fósiles de Ulloma. Anales de la Universidad de Chile 82: 499–506.</ref> In 1921, Florentino's brother [[Carlos Ameghino]] and Lucas Kraglievich described the species ''Megatherium gallardoi'' based on remains found in the Pampas of Northern Argentina, of Early-Middle Pleistocene age.<ref>C. Ameghino, L. Kraglievich Descripción del "''Megatherium gallardoi''" C. Amegh. descubierto en el Pampeano inferior de la ciudad de Buenos Aires Anales del Museo Nacional de Historia Natural de Buenos Aires, 31 (1921), pp. 134–156</ref><ref name=":15">Brandoni D., Soibelzon E. & Scarano A. 2008. — [https://sciencepress.mnhn.fr/en/periodiques/geodiversitas/30/4/sur-megatherium-gallardoi-mammalia-xenarthra-megatheriidae-et-les-megatheriinae-de-l-ensenadeen-pleistocene-inferieur-moyen-de-la-region-pampeenne-argentine On ''Megatherium gallardoi'' (Mammalia, Xenarthra, Megatheriidae) and the Megatheriinae from the Ensenadan (lower to middle Pleistocene) of the Pampean region, Argentina]. ''Geodiversitas'' 2008 (4): 793-804.</ref> In 2001, the species ''M. altiplanicum'' was described based on remains found in the Pliocene of Bolivia.<ref name=":3" /> In 2004, the species ''Megatherium urbinai'' was erected based on remains found in Pleistocene aged deposits in Peru.<ref name=":6">{{Cite journal |last1=Pujos |first1=François |last2=Salas |first2=Rodolfo |date=May 2004 |title=A new species of Megatherium (Mammalia: Xenarthra: Megatheriidae) from the Pleistocene of Sacaco and Tres Ventanas, Peru |url=https://onlinelibrary.wiley.com/doi/10.1111/j.0031-0239.2004.00376.x |journal=Palaeontology |language=en |volume=47 |issue=3 |pages=579–604 |doi=10.1111/j.0031-0239.2004.00376.x |bibcode=2004Palgy..47..579P |issn=0031-0239}}</ref> In 2006, the species ''Megatherium celendinense'' was erected for remains of Pleistocene age found in the Peruvian Andes.<ref name="Pujos2006">{{cite journal |last=Pujos |first=François |year=2006 |title=''Megatherium celendinense sp. nov.'' from the Pleistocene of the Peruvian Andes and the phylogenetic relationships of Megatheriines |journal=[[Palaeontology (journal)|Palaeontology]] |volume=49 |issue=2 |pages=285–306 |bibcode=2006Palgy..49..285P |doi=10.1111/j.1475-4983.2006.00522.x |s2cid=84225654 |doi-access=free}}</ref>