Ekgmowechashala (Sioux: "little cat man"[1][3]) is an extinct genus of primate belonging to Adapiformes.

Ekgmowechashala
Temporal range: 30.8–26.3 Ma
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Strepsirrhini
Infraorder: Adapiformes
Family: Ekgmowechashalidae
Genus: Ekgmowechashala
Macdonald, 1963[1]
Type species
Ekgmowechashala philotau
Macdonald, 1963[1]
Species
  • Ekgmowechashala philotau Macdonald, 1963[1]
  • Ekgmowechashala zancanellai Samuels, Albright, and Fremd, 2015[2]

Description and significance edit

With a weight of approximately 5 pounds (2.3 kg),[4] around 1 foot (0.3 m) tall and resembling a lemur,[5] Ekgmowechashala is the only known North American primate of its time; it lived during the late Oligocene and early Miocene.[5][6][7]

Classification edit

The classification of this form has long been problematic.[8] It was variously classified as a member of the extinct family Omomyidae (related to tarsiers) and the equally extinct Plagiomenidae (related to colugos), but has been recently reassigned to Adapiformes, the extinct relatives of lemurs and other strepsirrhines.[7][9][10][11] A cladistic analysis by Ni et al. (2016) reaffirmed the adapiform placement of Ekgmowechashala by recovering it as sister group to Bugtilemur, Gatanthropus, and Muangthanhinius in Ekgmowechashalidae.[12]

Paleobiology edit

The shape of its teeth,[13] and their likeness to those of raccoons, indicate that it ate soft fruit provided by the warm forests of the Rocky Mountains during the early Miocene.[14]

Fossils edit

Fossil evidence of Ekgmowechashala was discovered on the Pine Ridge Indian Reservation, an Oglala Sioux Native American reservation in South Dakota.[15] Molars were found in 1981 in the basin of John Day River, and these are in the collection of the Burke Museum of Natural History and Culture;[16] in the summer of 1997 John Zancanella of the Bureau of Land Management found a lower molar in the John Day Fossil Beds National Monument.[4][17][18]

Ekgmowechashala philotau, known from material in Nebraska and South Dakota, was thought to be the only species of this genus, but material from Oregon has been recently described as a new species, E. zancanellai. A tooth from the Toledo Bend Ranch Local Fauna of far eastern Texas has been assigned to this genus.[19]

See also edit

References edit

  1. ^ a b c d MacDonald, James Reid (1963). "The Miocene faunas from the Wounded Knee area of western South Dakota". Bulletin of the American Museum of Natural History. 125: 139–238. hdl:2246/1259.
  2. ^ Samuels, Joshua X.; Albright, L. Barry; Fremd, Theodore J. (2015). "The last fossil primate in North America, new material of the enigmatic Ekgmowechashala from the Arikareean of Oregon". American Journal of Physical Anthropology. 158 (1): 43–54. doi:10.1002/ajpa.22769. PMID 26118778.
  3. ^ Howells, William White (1997). Getting here: the story of human evolution. Howells House. p. 69. ISBN 978-0-929590-16-5. Retrieved 10 October 2010.
  4. ^ a b "25-Million-Year-Old Primate Fossil Dug Up at John Day Beds". The Columbian. 15 January 1998. Archived from the original on 4 November 2012. Retrieved 11 October 2010.
  5. ^ a b Bishop, Ellen Morris (2003). In search of ancient Oregon: a geological and natural history. Timber Press. p. 114. ISBN 978-0-88192-590-6. Retrieved 10 October 2010.
  6. ^ McKenna, Malcolm C.; Bell, Susan K. (1997). Classification of Mammals: Above the Species Level. Columbia University Press. p. 327. ISBN 978-0-231-11013-6.
  7. ^ a b Marivaux, Laurent; Chaimanee, Yaowalak; Tafforeau, Paul; Jaeger, Jean-Jacques (2006). "New strepsirrhine primate from the Late Eocene of peninsular Thailand (Krabi Basin)". American Journal of Physical Anthropology. 130 (4): 425–434. doi:10.1002/ajpa.20376. PMID 16444732.
  8. ^ Rose, Kenneth David (2006). The beginning of the age of mammals. JHU Press. p. 191. ISBN 978-0-8018-8472-6. Retrieved 10 October 2010.
  9. ^ Gunnell, Gregg F.; Kenneth D. Rose (2002). "Tarsiiformes: Evolutionary History and Adaptation". In Walter Carl Hartwig (ed.). The primate fossil record. Cambridge UP. pp. 45–82 [72]. Bibcode:2002prfr.book.....H. ISBN 978-0-521-66315-1. Retrieved 10 October 2010.
  10. ^ Cartmill, Matt; Fred H. Smith; Kaye B. Brown (2009). The Human Lineage. John Wiley and Sons. p. 115. ISBN 978-0-471-21491-5. Retrieved 10 October 2010.
  11. ^ Ni, Xijun; Meng, Jin; Beard, K. Christopher; Gebo, Daniel L.; Wang, Yuanqing; Li, Chuankui (2009). "A new tarkadectine primate from the Eocene of Inner Mongolia, China: phylogenetic and biogeographic implications". Proceedings of the Royal Society B. 277 (1679): 247–256. doi:10.1098/rspb.2009.0173. PMC 2842661. PMID 19386655.
  12. ^ Ni, X.; Li, Q.; Li, L.; Beard, K. C. (2016). "Oligocene primates from China reveal divergence between African and Asian primate evolution". Science. 352 (6286): 673–677. Bibcode:2016Sci...352..673N. doi:10.1126/science.aaf2107. PMID 27151861.
  13. ^ Fleagle, John C. (1999). Primate adaptation and evolution. Academic Press. p. 378. ISBN 978-0-12-260341-9. Retrieved 10 October 2010.
  14. ^ Delson, Eric; Ian Tattersall; John A. Van Couvering (2000). Encyclopedia of human evolution and prehistory. Taylor & Francis. p. 485. ISBN 978-0-8153-1696-1.
  15. ^ Mayor, Adrienne (2005). Fossil legends of the first Americans. Princeton UP. p. 242. ISBN 978-0-691-11345-6. Retrieved 11 October 2010.
  16. ^ PLSS data for the site, A5930 (Rudio Creek 4), are missing. Bryant, Laurie J. "Report on the Assessment of Vertebrate Paleontological Collections, Burke Museum of Natural History, University of Washington" (PDF). Burke Museum of Natural History and Culture. Archived from the original (PDF) on 17 June 2009. Retrieved 11 October 2010.
  17. ^ Mortenson, Eric. "Fossil Tooth Find Creates Stir". Eugene Register-Guard. Retrieved 11 October 2010.
  18. ^ "John Day Fossil Beds National Monument: Fossil List". National Park Service. Archived from the original on 30 June 2010. Retrieved 11 October 2010.
  19. ^ Albright III, L. Barry (2005). "Ekgmowechashala (Mammalia, ?Primates) from the Gulf coastal plain". Bulletin of the Florida Museum of Natural History. 45 (4): 355–361.