Glyptodont

Glyptodonts
Temporal range: EoceneLate Pleistocene (DivisaderanLujanian)
~38–0.011 Ma
Glyptodon fossil, Natural History Museum, Vienna
Illustration of the skeleton of Doedicurus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cingulata
Family: Chlamyphoridae
Subfamily: Glyptodontinae
Burmeister 1879
Genera

Glyptodonts are an extinct clade of large, heavily armoured armadillos, reaching up to 1.5 metres (4.9 ft) in height, and maximum body masses of around 2 tonnes. They had short, deep skulls, a fused vertebral column, and a large bony carapace made up of hundreds of individual scutes. Some glyptodonts had clubbed tails, similar to ankylosaurid dinosaurs.[1]

The earliest widely recognised fossils of glyptodonts in South America are known from the late Eocene, around 38 million years ago, and they spread to southern North America after the continents became connected around 2.7 million years ago.[2] The best-known genus within the group is Glyptodon.

Glyptodonts were historically considered to constitute the distinct family Glyptodontidae, with their relationships to modern armadillos being contested. In 2016, an analysis of the mitochondrial genome of Doedicurus found that it was, in fact, nested within the modern armadillos as the sister group of a clade consisting of Chlamyphorinae (fairy armadillos) and Tolypeutinae (giant, three-banded and naked-tailed armadillos). For this reason, glyptodonts and all armadillos but Dasypus (long-nosed or naked-tailed armadillos) were relocated to a new family, Chlamyphoridae, and glyptodonts were demoted to the subfamily Glyptodontinae.[2][1] Other authors have continued to use Glyptodontidae.[3] Based on the morphology of the inner ear, a close relationship with pampatheres has also been proposed.[4]

Glyptodonts abruptly became extinct approximately 12,000 years ago at the end of the Late Pleistocene, as part of the end-Pleistocene extinction event, along with most other large animals in the Americas. Evidence has been found suggesting that they were hunted by recently arrived Paleoindians, which may have played a role in their extinction.[3]

  1. ^ a b Mitchell, Kieren J.; Scanferla, Agustin; Soibelzon, Esteban; Bonini, Ricardo; Ochoa, Javier; Cooper, Alan (July 2016). "Ancient DNA from the extinct South American giant glyptodont Doedicurus sp. (Xenarthra: Glyptodontidae) reveals that glyptodonts evolved from Eocene armadillos". Molecular Ecology. 25 (14): 3499–3508. Bibcode:2016MolEc..25.3499M. doi:10.1111/mec.13695. hdl:11336/48521. ISSN 0962-1083. PMID 27158910. S2CID 3720645.
  2. ^ a b Delsuc, F.; Gibb, G. C.; Kuch, M.; Billet, G.; Hautier, L.; Southon, J.; Rouillard, J.-M.; Fernicola, J. C.; Vizcaíno, S. F.; MacPhee, R. D.E.; Poinar, H. N. (2016-02-22). "The phylogenetic affinities of the extinct glyptodonts". Current Biology. 26 (4): R155–R156. Bibcode:2016CBio...26.R155D. doi:10.1016/j.cub.2016.01.039. hdl:11336/49579. PMID 26906483.
  3. ^ a b Carlini, Alfredo A.; Carrillo-Briceño, Jorge D.; Jaimes, Arturo; Aguilera, Orangel; Zurita, Alfredo E.; Iriarte, José; Sánchez-Villagra, Marcelo R. (December 2022). "Damaged glyptodontid skulls from Late Pleistocene sites of northwestern Venezuela: evidence of hunting by humans?". Swiss Journal of Palaeontology. 141 (1): 11. Bibcode:2022SwJP..141...11C. doi:10.1186/s13358-022-00253-3. ISSN 1664-2376.
  4. ^ Tambusso, P. Sebastián; Varela, Luciano; Góis, Flávio; Moura, Jorge Felipe; Villa, Chiara; Fariña, Richard A. (June 2021). "The inner ear anatomy of glyptodonts and pampatheres (Xenarthra, Cingulata): Functional and phylogenetic implications". Journal of South American Earth Sciences. 108: 103189. Bibcode:2021JSAES.10803189T. doi:10.1016/j.jsames.2021.103189. S2CID 234062118.