Equus neogeus
Equus neogeus is an extinct species of equine native to South America during the Pleistocene. It was formerly thought to be several distinct species within the subgenus Amerhippus, but was later shown to be a single morphologically variable species. It is thought to be closely related to true horses.
| Equus neogeus | |
|---|---|
| Skull | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Perissodactyla |
| Family: | Equidae |
| Genus: | Equus |
| Species: | †E. neogeus |
| Binomial name | |
| †Equus neogeus Lund, 1840 | |
| Synonyms | |
| |
Taxonomy edit
While they have formerly been referred to as belonging to 5 separate species, this has been revised down into three,[1] and more recently a single, morphologically variable species Equus neogeus.[2][3] Some authors continue to recognise three species, restricting Equus neogeus to large-sized individuals spanning from the Pampas to Northeast Brazil, while separating the smaller Equus andium for populations in the northern-central Andes, and Equus insulatus for medium-sized animals spanning from Bolivia to Venezuela. These authors suggest that E. insulatus was the ancestor of the other species.[4] Historically, South American Equus species were placed in the subgenus Amerhippus, but this has subsequently been questioned.[4] A 2008 study of mitochondrial DNA fragments of a specimen of E. neogeus found it to be nested within mitochondrial lineages of E. caballus,[5] however, later studies suggested that this result required more specimens to be analysed for confirmation.[6] A close relationship to caballine horses was also supported by a 2019 morphological analysis study.[7]
Description edit
Equus neogeus measured roughly 1.5 m (4.9 ft) tall and weighed approximately 400 kg (880 lb).[8]
Distribution edit
They were one of two groups of equines in South America, alongside Hippidion.[9] Fossils have been recovered from the Tarija Formation of Bolivia, the Serranía del Perijá in Venezuela, the Chiu-Chiu Formation of Chile, the Sabana Formation of the Bogotá savanna in Colombia,[10] and from various locations in Ecuador.[8] Equus first appeared in South America during the late Early Pleistocene-earliest Middle Pleistocene, around 1 to 0.8 million years ago, based on remains found near Tarija, Bolivia.[11]
Paleobiology edit
A 2019 study suggested that Equus neogeus specimens from Uruguay were primarily grazers that fed on both C4 and C3 grasses in prairies and open woodlands.[12]
Extinction edit
Equus neogeus became extinct at the end of the Late Pleistocene as part of the Quaternary extinction event, along with the vast majority of other large mammals in South America.[13] The youngest remains date to approximately 11,700 years Before Present (BP), in Río Quequén Salado, in the southwest of Buenos Aires province, Argentina.[11] At the Arroyo Seco 2 site in the Argentinian Pampas, remains of Equus neogeus are associated with human artifacts, indicating that they were butchered by humans at the site, which dates to 14,782–11,142 cal yr BP, suggesting that hunting by recently arrived humans may have played a role in its extinction.[14]
References edit
- ^ Prado, J. L., and Alberdi, M. T. (2017). Fossil Horses of South America. Springer International Publishing, 150
- ^ Machado, Helena; Grillo, Orlando; Scott, Eric; Avilla, Leonardo (September 2018). "Following the Footsteps of the South American Equus: Are Autopodia Taxonomically Informative?". Journal of Mammalian Evolution. 25 (3): 397–405. doi:10.1007/s10914-017-9389-6. ISSN 1064-7554. S2CID 22113020.
- ^ Machado, Helena; Avilla, Leonardo (2019-07-03). "The Diversity of South American Equus: Did Size Really Matter?". Frontiers in Ecology and Evolution. 7: 235. doi:10.3389/fevo.2019.00235. ISSN 2296-701X.
- ^ a b Prado, José; Alberdi, María (2023). "DIVERSIDAD DE LOS ÉQUIDOS FÓSILES DE AMÉRICA DEL SUR Autores/as". Publicación Electrónica de la Asociación Paleontológica Argentina. doi:10.5710/PEAPA.06.06.2022.415.
- ^ Orlando, Ludovic; Male, Dean; Alberdi, Maria Teresa; Prado, Jose Luis; Prieto, Alfredo; Cooper, Alan; Hänni, Catherine (May 2008). "Ancient DNA Clarifies the Evolutionary History of American Late Pleistocene Equids". Journal of Molecular Evolution. 66 (5): 533–538. Bibcode:2008JMolE..66..533O. doi:10.1007/s00239-008-9100-x. ISSN 0022-2844. PMID 18398561. S2CID 19069554.
- ^ Barrón-Ortiz, Christina I.; Rodrigues, Antonia T.; Theodor, Jessica M.; Kooyman, Brian P.; Yang, Dongya Y.; Speller, Camilla F. (2017-08-17). Orlando, Ludovic (ed.). "Cheek tooth morphology and ancient mitochondrial DNA of late Pleistocene horses from the western interior of North America: Implications for the taxonomy of North American Late Pleistocene Equus". PLOS ONE. 12 (8): e0183045. Bibcode:2017PLoSO..1283045B. doi:10.1371/journal.pone.0183045. ISSN 1932-6203. PMC 5560644. PMID 28817644.
- ^ Barrón-Ortiz, Christina I.; Avilla, Leonardo S.; Jass, Christopher N.; Bravo-Cuevas, Víctor M.; Machado, Helena; Mothé, Dimila (2019-09-12). "What Is Equus? Reconciling Taxonomy and Phylogenetic Analyses". Frontiers in Ecology and Evolution. 7: 343. doi:10.3389/fevo.2019.00343. ISSN 2296-701X.
- ^ a b Prado, J. L.; Alberdi, M. A. T.; De Reyes, M. N. L.; Poiré, D. G.; Canalicchio, J. M. (2013). "New material of Equus (Amerhippus) neogeus (Mammalia, Perissodactyla) from the late Pleistocene of Olavarría (Argentina)". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 269 (2): 125. doi:10.1127/0077-7749/2013/0340. hdl:10261/115119.
- ^ PRADO, JOSE LUIS; ALBERDI, MARIA TERESA (2018). FOSSIL HORSES OF SOUTH AMERICA : phylogeny, systemics and ecology. SPRINGER INTERNATIONAL PU. doi:10.1007/978-3-319-55877-6. ISBN 978-3-319-85769-5. OCLC 1048948248. S2CID 164732480.
- ^ De Porta, Jaime. 1960. Los Equidos fósiles de la Sabana de Bogotá. Boletín de Geología, Universidad Industrial de Santander 4. 51–78. Accessed 2017-03-30.
- ^ a b Cirilli, Omar; Machado, Helena; Arroyo-Cabrales, Joaquin; Barrón-Ortiz, Christina I.; Davis, Edward; Jass, Christopher N.; Jukar, Advait M.; Landry, Zoe; Marín-Leyva, Alejandro H.; Pandolfi, Luca; Pushkina, Diana; Rook, Lorenzo; Saarinen, Juha; Scott, Eric; Semprebon, Gina (September 2022). "Evolution of the Family Equidae, Subfamily Equinae, in North, Central and South America, Eurasia and Africa during the Plio-Pleistocene". Biology. 11 (9): 1258. doi:10.3390/biology11091258. ISSN 2079-7737. PMC 9495906. PMID 36138737.
- ^ Morosi, Elizabeth; Ubilla, Martin (December 2019). "Feeding and environmental studies on late Pleistocene horses in mid-latitudes of South America (northern Uruguay)". Quaternary Science Reviews. 225: 106025. Bibcode:2019QSRv..22506025M. doi:10.1016/j.quascirev.2019.106025. S2CID 210240458.
- ^ Anthony D. Barnosky; Paul L. Koch; Robert S. Feranec; Scott L. Wing; Alan B. Shabel (2004). "Assessing the Causes of Late Pleistocene Extinctions on the Continents". Science. 306 (5693): 70–75. Bibcode:2004Sci...306...70B. CiteSeerX 10.1.1.574.332. doi:10.1126/science.1101476. PMID 15459379. S2CID 36156087.
- ^ Bampi, Hugo; Barberi, Maira; Lima-Ribeiro, Matheus S. (December 2022). "Megafauna kill sites in South America: A critical review". Quaternary Science Reviews. 298: 107851. Bibcode:2022QSRv..29807851B. doi:10.1016/j.quascirev.2022.107851. S2CID 253876769.