Thalassocnus

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The content is sourced from: https://handwiki.org/wiki/Biology:Thalassocnus

Thalassocnus is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—T. antiquus, T. natans, T. littoralis, T. carolomartini, and T. yuacensis—represent a chronospecies, a population gradually adapting to marine life in one direct lineage. They are the only known aquatic sloths. They have been found in the Pisco Formation of Peru and the Bahía Inglesa, Coquimbo, and Horcón formations of Chile. Thalassocninae has been placed in both the families Megatheriidae and Nothrotheriidae. Thalassocnus evolved several marine adaptations over the course of 4 million years, such as dense and heavy bones to counteract buoyancy, the internal nostrils migrating farther into the head to help with breathing while completely submerged, the snout becoming wider and more elongated to consume aquatic plants better, and the head angling farther and farther downwards to aid in bottom feeding. The long tail was probably used for diving and balance similarly to the modern day beaver (Castor spp.) and platypus (Ornithorhynchus anatinus). Thalassocnus probably walked across the seafloor and dug up food with its claws. They probably could not do high-powered swimming, relying on paddling if necessary. Early Thalassocnus were probably generalist grazers eating seaweed and seagrasses close to shore, whereas later species specialized on seagrasses farther off the coast. They were probably preyed upon by sharks and macroraptorial sperm whales such as Acrophyseter. Thalassocnus were found in formations with large marine mammal and shark assemblages.

macroraptorial aquatic plants angling

References

de Muizon, C.; McDonald, H. G.; Salas-Gismondi, R.; Schmitt, M. U. (2004). "The youngest species of the aquatic sloth Thalassocnus and a reassessment of the relationships of the nothrothere sloths (Mammalia: Xenarthra)". Journal of Vertebrate Paleontology 24 (2): 387–397. doi:10.1671/2429a. https://www.researchgate.net/publication/232672313.
Canto, J.; Salas-Gismondi, R.; Cozzuol, M.; Yáñez, J. (2008). "The aquatic sloth Thalassocnus (Mammalia, Xenarthra) from the late Miocene of North-Central Chile: biogeographic and ecological implications". Journal of Vertebrate Paleontology 28 (3): 918–922. doi:10.1671/0272-4634(2008)28[918:TASTMX2.0.CO;2]. ISSN 0272-4634. https://dx.doi.org/10.1671%2F0272-4634%282008%2928%5B918%3ATASTMX%5D2.0.CO%3B2
De los Arcos, S.; Partarrieu, D.; Carrillo-Briceño, J.; Amson, E. (2017). "The southernmost occurrence of the aquatic sloth Thalassocnus (Mammalia, Tardigrada) in two new Pliocene localities in Chile". Ameghiniana 54 (4): 351–369. doi:10.5710/AMGH.29.12.2016.3004. https://www.researchgate.net/publication/312026297.
Peralta-Prato, Javiera; Solórzano, Andrés (2019). "How many species of the aquatic sloth Thalassocnus (Xenarthra: Megatheriidae) were in Chile?: new evidences from the Bahía Inglesa Formation, with a reappraisal of their biochronological affinities". Andean Geology 46 (3): 693. doi:10.5027/andgeoV46n3-3221. https://dx.doi.org/10.5027%2FandgeoV46n3-3221
de Muizon, C.; McDonald, H. G. (1995). "An aquatic sloth from the Pliocene of Peru". Nature 375 (6528): 224–227. doi:10.1038/375224a0. Bibcode: 1995Natur.375..224M. https://dx.doi.org/10.1038%2F375224a0
McDonald, H. G.; de Muizon, C. (2002). "The cranial anatomy of Thalassocnus (Xenarthra, Mammalia), a derived nothrothere from the Neogene of the Pisco Formation (Peru)". Journal of Vertebrate Paleontology 22 (2): 349–365. doi:10.1671/0272-4634(2002)022[0349:TCAOTX2.0.CO;2]. https://dx.doi.org/10.1671%2F0272-4634%282002%29022%5B0349%3ATCAOTX%5D2.0.CO%3B2
de Muizon, C.; McDonald, H. G.; Salas, R.; Urbina, M. (2003). "A new early species of the aquatic sloth Thalassocnus (Mammalia, Xenarthra) from the late Miocene of Peru". Journal of Vertebrate Paleontology 23 (4): 886–894. doi:10.1671/2361-13. https://dx.doi.org/10.1671%2F2361-13
Hoffstetter, R. (1968). "Un gisement de vertébrés tertiaires à Sacaco (Sud-Pérou), témoin néogène d'une migration de faunes australes au long de la côte occidentale sudaméricaine" (in fr). Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences 267: 1273–1276.
Amson, E.; de Muizon, C.; Gaudin, T. J. (2017). "A reappraisal of the phylogeny of the Megatheria (Mammalia: Tardigrada), with an emphasis on the relationships of the Thalassocninae, the marine sloths". Zoological Journal of the Linnean Society 179 (1): 217–236. doi:10.1111/zoj.12450. https://dx.doi.org/10.1111%2Fzoj.12450
Varela, L.; Tambusso, P.S.; McDonald, H.G.; Fariña, R.A.; Fieldman, M. (2019). "Phylogeny, Macroevolutionary Trends and Historical Biogeography of Sloths: Insights From a Bayesian Morphological Clock Analysis". Systematic Biology 68 (2): 204–218. doi:10.1093/sysbio/syy058. PMID 30239971. https://dx.doi.org/10.1093%2Fsysbio%2Fsyy058
Presslee, S.; Slater, G.J.; Pujos, F.; Forasiepi, A.M.; Fischer, R.; Molloy, K.; Mackie, M.; Olsen, J.V. et al. (July 2019). "Palaeoproteomics resolves sloth relationships". Nature Ecology & Evolution 3 (7): 1121–1130. doi:10.1038/s41559-019-0909-z. PMID 31171860. http://www.nature.com/articles/s41559-019-0909-z.
de Muizon, C.; McDonald, H. G.; Salas, R.; Urbina, M. (2004). "The evolution of feeding adaptations of the aquatic sloth Thalassocnus". Journal of Vertebrate Paleontology 24 (2): 398–410. doi:10.1671/2429b. https://dx.doi.org/10.1671%2F2429b
Rincón, A. D.; McDonald, H. G.; Solórzano, A.; Flores, M. N.; Ruiz-Ramoni, D. (2015). "A new enigmatic Late Miocene mylodontoid sloth from northern South America". Royal Society Open Science 2 (2): 140256. doi:10.1098/rsos.140256. PMID 26064594. Bibcode: 2015RSOS....240256R. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4448802
Amson, E.; Argot, C.; McDonald, H. G.; de Muizon, C. (2015). "Osteology and functional morphology of the axial postcranium of the marine sloth Thalassocnus (Mammalia, Tardigrada) with paleobiological implications". Journal of Mammalian Evolution 22 (4): 473–518. doi:10.1007/s10914-014-9280-7. https://dx.doi.org/10.1007%2Fs10914-014-9280-7
Amson, E.; de Muizon, C.; Laurin, M.; Argot, C.; Buffrénil, V. de (2014). "Gradual adaptation of bone structure to aquatic lifestyle in extinct sloths from Peru". Proceedings of the Royal Society B: Biological Sciences 281 (1782): 20140192. doi:10.1098/rspb.2014.0192. PMID 24621950. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3973278
De Muizon, Christian; McDonald, H. Gregory; Salas, Rodolfo; Urbina, Mario (2004). "The Youngest Species of the Aquatic Sloth Thalassocnus and a Reassessment of the Relationships of the Nothrothere Sloths (Mammalia: Xenarthra)". Journal of Vertebrate Paleontology 24 (2): 387–397. doi:10.1671/2429a. https://www.jstor.org/stable/4524726.
Amson, E.; Argot, C.; McDonald, H. G.; de Muizon, C. (2004). "Osteology and functional morphology of the hind limb of the marine sloth Thalassocnus (Mammalia, Tardigrada)". Journal of Mammalian Evolution 22 (3): 355–419. doi:10.1007/s10914-014-9274-5. https://hal.sorbonne-universite.fr/hal-01188790/file/Amson_2014_Osteology_and.pdf.
Kuo, J. (2005). "A revision of the genus Heterozostera (Zosteraceae)". Aquatic Botany 81 (2): 97–140. doi:10.1016/j.aquabot.2004.10.005. https://dx.doi.org/10.1016%2Fj.aquabot.2004.10.005
Pyenson, N. D.; Gutstein, C. S.; Parham, J. F.; Le Roux, J. P.; Chavarría, C. C.; Little, H.; Metallo, A.; Rossi, V. et al. (2014). "Repeated mass strandings of Miocene marine mammals from Atacama Region of Chile point to sudden death at sea". Proceedings of the Royal Society B 281 (1781): 1–9. doi:10.1098/rspb.2013.3316. PMID 24573855. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3953850
Lambert, O.; Bianucci, G.; de Muizon, C. (2017). "Macroraptorial sperm whales (Cetacea, Odontoceti, Physeteroidea) from the Miocene of Peru". Zoological Journal of the Linnean Society 179: 404–474. doi:10.1111/zoj.12456. https://www.researchgate.net/publication/307936921.
Parham, J. F.; Pyenson, N. D. (2010). "New sea turtle from the Miocene of Peru and iterative evolution of feeding ecomorphologies since the Cretaceous". Journal of Paleontology 84 (2): 231–247. doi:10.1666/09-077R.1. https://repository.si.edu/bitstream/handle/10088/17511/paleo_Parham_Pyenson_2010_JPaleo.pdf.
Brand, L.; Urbina, M.; Chadwick, A.; DeVries, T. J.; Esperante, R. (2011). "A high resolution stratigraphic framework for the remarkable fossil cetacean assemblage of the Miocene/Pliocene Pisco Formation, Peru". Journal of South American Earth Sciences 31 (4): 414–425. doi:10.1016/j.jsames.2011.02.015. Bibcode: 2011JSAES..31..414B. https://dx.doi.org/10.1016%2Fj.jsames.2011.02.015
Bianucci, G.; Di Celma, C.; Landini, W.; Post, K.; Tinelli, C.; de Muizon, C.; Gariboldi, K.; Malinverno, E. et al. (2015). "Distribution of fossil marine vertebrates in Cerro Colorado, the type locality of the giant raptorial sperm whale Livyatan melvillei (Miocene, Pisco Formation, Peru)". Journal of Maps 12 (3): 543. doi:10.1080/17445647.2015.1048315. http://www.vliz.be/imisdocs/publications/302166.pdf.
Suárez, M. E.; Encinas, A.; Ward, D. (2006). "An Early Miocene elasmobranch fauna from the Navidad Formation, Central Chile, South America". Cainozoic Research 4 (1–2): 3–18. http://natuurtijdschriften.nl/download?type=document;docid=541712.
Sallaberry, M.; Rubilar-Rogers, D.; Suárez, M. E.; Gutstein, C. S. (2007). "The skull of a fossil Prion (Aves: Procellariiformes) from the Neogene (Late Miocene) of northern Chile". Revista Geológica de Chile 34 (1): 147–154. doi:10.4067/S0716-02082007000100008. https://dx.doi.org/10.4067%2FS0716-02082007000100008
Staig, F.; Hernández, S.; López, P.; Villafaña, J. A.; Varas, C.; Soto, L. P.; Briceño, J. D. C. (2015). "Late Neogene elasmobranch fauna from the Coquimbo Formation, Chile". Revista Brasileira de Paleontologia 18 (2): 261–272. doi:10.4072/rbp.2015.2.07. https://www.researchgate.net/publication/283285140.
Briceño, J. D. C.; Gonzales-Barba, G.; Landaeta, M. F.; Nielsen, S. N. (2013). "Condrictios fósiles del Plioceno Superior de la Formación Horcón, Región de Valparaíso, Chile central" (in es). Revista Chilena de Historia Natural 86 (2): 191–206. doi:10.4067/S0716-078X2013000200008. http://rchn.biologiachile.cl/pdfs/2013/2/08_Carrillo-Briceno_et_al_2013.pdf.
Hoffmeister, M. C.; Carrillo Briceño, J. D.; Nielsen, S. N. (2014). "The evolution of seabirds in the Humboldt Current: new clues from the Pliocene of Central Chile". PLOS ONE 9 (3): e90043. doi:10.1371/journal.pone.0090043. PMID 24621560. Bibcode: 2014PLoSO...990043C. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3951197

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