American cheetah

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American cheetah
Temporal range: Late Pliocene to Late Pleistocene 2.6–0.012 Ma
Miracinonyx (american cheetah).png
Artist's rendition of M. trumani
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Suborder: Feliformia
Family: Felidae
Subfamily: Felinae
Genus: Miracinonyx
Adams, 1979
Type species
Crocuta inexpectata
Cope, 1895
Species
  • M. inexpectatus (Cope, 1895) sensu Adams, 1979
  • M. trumani (Orr, 1969) sensu Adams, 1979
Synonyms
M. inexpectatus synonymy
  • Crocuta inexpectata Cope, 1895
  • Uncia inexpectata (Cope, 1895) sensu Cope, 1899
  • Felis longricus Brown, 1908
  • Felis concolor Brown, 1908
  • Smilodontopsis mooreheadi Hay, 1922
  • Felis (Puma) inexpectata (Cope, 1895) sensu Simpson, 1941
  • Felis studeri Savage, 1960
  • Acinonyx studeri (Savage, 1960) sensu Kurtén & Anderson, 1980
  • Acinonyx inexpectatus (Cope, 1895) sensu Kurtén & Anderson, 1980
M. trumani synonymy
  • Felis concolor Wilson, 1942
  • Felis trumani Orr, 1969
  • Acinonyx trumani (Orr, 1969) sensu Kurtén & Anderson, 1980

The American cheetah is either of two feline species of the extinct genus Miracinonyx, endemic to North America during the Pleistocene epoch (2.6 million to 12,000 years ago) and morphologically similar to the modern cheetah (Acinonyx jubatus).[1] These cats were originally known from fragments of skeletons, but nearly complete skeletons have been recovered from Natural Trap Cave in northern Wyoming.[2]

The two species commonly identified are M. inexpectatus and M. trumani. Sometimes, a third species, M. studeri, is included, but it is more often listed as a junior synonym of M. inexpectatus. Both species are similar to the modern cheetah, with faces shortened and nasal cavities expanded for increased oxygen capacity, and legs proportioned for swift running. However, these similarities may not be inherited from a common ancestor, but may instead result from either parallel or convergent evolution. These were larger than a modern cheetah and similar in size to a modern northern cougar. Body mass was typically around 70 kg (150 lb), with a head-and-body length of 170 cm (67 in), tail length around 92 cm (36 in), and shoulder height of 85 cm (33 in).[3] Large specimens could have weighed more than 95 kg (209 lb).[4]

Discovery and naming[edit]

Fossils attributed to American cheetahs were first described from several isolated teeth from Port Kennedy Cave from Pennsylvania, dating back to the Irvingtonian age. The American paleontologist Edward Drinker Cope considered these to be related to the spotted hyena, and described the material as Crocuta inexpectata in 1895.[5] In 1899 he reclassified the specimens as related to the snow leopard, Unicia inexpectata.[6] More fossil material were recovered from similar age deposits in Maryland and Arkansas, where in 1941 American paleontologist George Gaylord Simpson found them all belonging to the same animal, one he considered to be more closely related to the cougar (naming the animal as Felis (Puma) inexpectata.[7] A second species, Felis studeri, was described by Savage in 1960 based on a more complete material consisting of extensive postcranial and cranial material of the animal.[8] However, a 1976 review of fossil pumas from Kurtén considered F. inexpectata and F. studeri to be the same species, with F. inexpectata having priority. The other valid species (then as Felis trumani) was described in 1969 by Orr based on a complete skull from the Late Pleistocene found in Crypt Cave, Nevada.[9]

In 1979 Adams found these animals to be intermediates between cheetahs and cougars and decided to placed them in their own genus Miracinonyx. The name is a combination of the Latin "mir" (wonderful) and Acinonyx, which is a combination of the Greek for ἁκινητος (akinitos) meaning 'unmoved' or 'motionless', and ὄνυξ (onyx) meaning 'nail' or 'hoof.[10]

Fossil distribution[edit]

Fossil remains of Miracinonyx have been found across the United States. Fossils of M. trumani have been found in Arizona,[11] Florida, Wyoming,[12] Colorado,[13] Nebraska, South Carolina,[14] Maryland and Pennsylvania.[15] The most complete finds of M. trumani are from the Natural Trap Cave in northern Wyoming.[16] Fossil remains of M. inexpectatus found in Hamilton Cave in West Virginia show that this creature lived with and competed with other large cats like jaguars and saber-toothed cats.[9][17] Fossils of M. inexpectatus have also been found in Florida,[18][19] Texas,[20] Colorado, Georgia,[21] South Carolina,[22][23] Pennsylvania, Maryland,[24] and California.[25][15] In 2022, the skeletal remains of a M. inexpectatus were retrieved from a cave in southwest Virginia.[26]

Taxonomy and evolution[edit]

Research into the American cheetah has been contradictory. It was originally believed to be an early cougar representative, before being reclassified in the 1970s as a close relative of the cheetah.[10] This suggested that the ancestors of the cheetah diverged from the Puma lineage in the Americas and migrated back to the Old World, a claim repeated as recently as 2006 by Johnson et al.,[27] and in 2015 by Dobrynin et al.[28] However, other research by Barnett and Faurby, through examining mitochondrial DNA and reanalyzing morphology, has suggested reversing the reclassification: the American cheetah developed cheetah-like characteristics through parallel evolution, but it is most closely related to Puma and not to the modern cheetah of Africa and Asia.[9][29][30] Moreover, Faurby notes that no Acinonyx fossils have been found in North America, and no Miracinonyx fossils elsewhere. However, O'Brien et al. (2016) posit that the supposed homoplasy between the genera is controversial, as it is asserted that is not necessarily any conclusive anatomical or genetic basis for dismissing a homologous relationship between Acinonyx and Miracinonyx.[31] The veracity of the origin of the modern cheetah is also debated; however, Miracinonyx is believed to have evolved from cougar-like ancestors, regardless of whether in the Old World or the New World.

The cougar and M. trumani are believed to have split from a cougar-like ancestor around three million years ago;[29] where M. inexpectatus fits in is unclear, although it is probably a more primitive version of M. trumani.[32]

Below is the phylogeny from Chimento and Dondas (2017) when describing the earliest known fossil record of cougars in South America. As shown here, they found Miracinonyx to be a sister taxon to Puma (though in their paper they considered the former genus to be an extinct subgenus of the latter).[33]

Miracinonyx

M. inexpectatus

M. trumani

Puma

P. concolor

P. pumoides

H. yagouaroundi

References[edit]

  1. ^ "Miracinonyx Adams 1979 (American cheetah)". Fossilworks website. Retrieved 2013-12-02.
  2. ^ "Late Pleistocene, paleoecology and large mammal taphonomy, Natural Trap Cave, Wyoming". National Geographic Research & Exploration. 1993. Retrieved 2017-06-20.
  3. ^ "Extinct American Cheetah, Miracinonyx inexpectatus". San Diego Zoo factsheet. July 2010. Archived from the original on 2016-03-04. Retrieved 2013-12-02.
  4. ^ Caro, T.M. (1994). Cheetahs of the Serengeti Plains: Group Living in an Asocial Species. Chicago: University of Chicago Press. p. 500. ISBN 978-0226094335.
  5. ^ Edw. D. Cope. (1895). The fossil vertebrata from the fissure at Port Kennedy, Pa. Proceedings of the Academy of Natural Sciences of Philadelphia, 446-450.
  6. ^ Cope, E. D. (1899). Vertebrate remains from Port Kennedy bone deposit.
  7. ^ Simpson, George Gaylord (1941). "Large Pleistocene felines of North America. American Museum novitates ; no. 1136".
  8. ^ Savage, D. E. (1960). A Survey of Various Late Cenozoic Vertebrate Faunas of the Panhandle of Texas: Felidae. University of California Press.
  9. ^ a b c Van Valkenburgh, Blaire; Grady, Frederick; Kurtén, Björn (1990). "The Plio-Pleistocene Cheetah-Like Cat Miracinonyx inexpectatus of North America". Journal of Vertebrate Paleontology. 10 (4): 434–454. doi:10.1080/02724634.1990.10011827. ISSN 0272-4634. JSTOR 4523343.
  10. ^ a b Adams, Daniel B. (14 September 1979). "The Cheetah: Native American". Science. 205 (4411): 1155–1158. Bibcode:1979Sci...205.1155A. doi:10.1126/science.205.4411.1155. PMID 17735054. S2CID 17951039.
  11. ^ "American Cheetah Fossil (U.S. National Park Service)". www.nps.gov. Retrieved 2021-09-13.
  12. ^ MARTIN, L. D.; GILBERT, B. M.; ADAMS, D. B. (1977-03-11). "A Cheetah-Like Cat in the North American Pleistocene". Science. 195 (4282): 981–982. Bibcode:1977Sci...195..981M. doi:10.1126/science.195.4282.981. ISSN 0036-8075. PMID 17735673. S2CID 38895439.
  13. ^ Emslie, Steven D. (January 1986). "Late Pleistocene vertebrates from Gunnison County, Colorado". Journal of Paleontology. 60 (1): 170–176. doi:10.1017/s0022336000021612. ISSN 0022-3360.
  14. ^ Sanders, Albert E. (2002). "Additions to the Pleistocene Mammal Faunas of South Carolina, North Carolina, and Georgia". Transactions of the American Philosophical Society. 92 (5): i. doi:10.2307/4144916. ISSN 0065-9746. JSTOR 4144916.
  15. ^ a b Autin, Beth. "LibGuides: Extinct American Cheetahs (Miracinonyx spp.) Fact Sheet: Distribution & Habitat". ielc.libguides.com. Retrieved 2021-08-29.
  16. ^ Wang, Xiaoming; Martin, Larry (1993-01-01). "Late Pleistocene, paleoecology and large mammal taphonomy, Natural Trap Cave, Wyoming". National Geographic Research & Exploration. 9: 422–435.
  17. ^ The microtine rodents of the Cheetah Room fauna, Hamilton Cave, West Virginia, and the spontaneous origin of Synaptomys (Report). 1988. doi:10.3133/b1853.
  18. ^ Scott, M.; Gary, S. (1987). Late Pliocene (Late Blancan) vertebrates from the St. Petersburg Times site, Pinellas County, Florida, with a brief review of Florida Blancan faunas. Florida Paleontological Society. OCLC 182860777.
  19. ^ Simpson, G.G. (1929). Pleistocene mammalian fauna of the Seminole Field, Pinellas County, Florida. American Museum of Natural History. OCLC 729432.
  20. ^ Slaughter, B.H. (1966). "The Moore Pit Local Fauna; Pleistocene of Texas". Journal of Paleontology. 40 (1): 78–91. ISSN 0022-3360. JSTOR 1301775.
  21. ^ Sanders, A.E. (2002). "Additions to the Pleistocene Mammal Faunas of South Carolina, North Carolina, and Georgia". Transactions of the American Philosophical Society. 92 (5): i. doi:10.2307/4144916. ISSN 0065-9746. JSTOR 4144916.
  22. ^ Sanders, A.E. (2002). "Additions to the Pleistocene Mammal Faunas of South Carolina, North Carolina, and Georgia". Transactions of the American Philosophical Society. 92 (5): i. doi:10.2307/4144916. ISSN 0065-9746. JSTOR 4144916.
  23. ^ Kohn, M.J.; McKay, M.P.; Knight, J.L. (2005). "Dining in the Pleistocene—Who's on the menu?". Geology. 33 (8): 649–652. doi:10.1130/g21476ar.1. ISSN 1943-2682.
  24. ^ Gidley, J.W. (1913). "Preliminary report on a recently discovered Pleistocene cave deposit near Cumberland, Maryland". Proceedings of the United States National Museum. 46 (2014): 93–102. doi:10.5479/si.00963801.46-2014.93. ISSN 0096-3801.
  25. ^ "Fossil history of the panther (Puma concolor) and the cheetah-like cat (Miracinonyx inexpectatus) in Florida". ufdc.ufl.edu. Retrieved 2021-08-25.
  26. ^ Wade, S. (2022). "Caving team discovers, retrieves rare ice age-era cat skeleton from Southwest Virginia cave". Cardinal News. Retrieved 2022-01-26.
  27. ^ Johnson, W.E.; Eizirik, E.; Pecon-Slattery, J.; Murphy, W.J.; Antunes, A.; Teeling, E. & O'Brien, S.J. (6 January 2006). "The Late Miocene radiation of modern Felidae: A genetic assessment". Science. 311 (5757): 73–77. Bibcode:2006Sci...311...73J. doi:10.1126/science.1122277. PMID 16400146. S2CID 41672825.
  28. ^ Dobrynin, Pavel; Liu, Shiping; Tamazian, Gaik; Xiong, Zijun; Yurchenko, Andrey A.; Krasheninnikova, Ksenia; Kliver, Sergey; Schmidt-Küntzel, Anne; Koepfli, Klaus-Peter (2015-01-01). "Genomic legacy of the African cheetah, Acinonyx jubatus". Genome Biology. 16: 277. doi:10.1186/s13059-015-0837-4. ISSN 1474-7596. PMC 4676127. PMID 26653294.
  29. ^ a b Barnett, Ross; Barnes, Ian; Phillips, Matthew J.; Martin, Larry D.; Harington, C. Richard; Leonard, Jennifer A.; Cooper, Alan (9 August 2005). "Evolution of the extinct Sabretooths and the American cheetah-like cat". Current Biology. 15 (15): R589–R590. doi:10.1016/j.cub.2005.07.052. PMID 16085477. S2CID 17665121.
  30. ^ Faurby, S.; Werdelin, L.; Svenning, J. C. (2016-05-05). "The difference between trivial and scientific names: There were never any true cheetahs in North America". Genome Biology. 17: 89. doi:10.1186/s13059-016-0943-y. ISSN 1474-7596. PMC 4858926. PMID 27150269.
  31. ^ O’Brien, Stephen J.; Koepfli, Klaus Peter; Eizirik, Eduardo; Johnson, Warren; Driscoll, Carlos; Antunes, Agostinho; Schmidt-Kuntzel, Anne; Marker, Laurie; Dobrynin, Pavel (2016-01-01). "Response to Comment by Faurby, Werdelin and Svenning". Genome Biology. 17: 90. doi:10.1186/s13059-016-0942-z. ISSN 1474-760X. PMC 4858819. PMID 27150130.
  32. ^ Haaramo, Mikko (2005-11-15). "Mikko's Phylogeny Archive - Felidae: Felinae – small cats". Archived from the original on 2007-03-27. Retrieved 2007-02-20.
  33. ^ Chimento, N.R.; Dondas, A. (2017). "First record of Puma concolor (Mammalia, Felidae) in the Early-Middle Pleistocene of South America". Journal of Mammalian Evolution. 25 (3): 381–389. doi:10.1007/s10914-017-9385-x. S2CID 16249074.