Editing Smilodon (section)

== Extinction ==

[[File:Panthera leo atrox and Smilodon fatalis Page.jpg|thumb|left|Skeletons of ''S. fatalis'' (left) and the [[American lion]], two large North American [[felids]] which went [[extinct]] during the [[Late Pleistocene]], George C. Page Museum]]
Along with most of the New World Pleistocene megafauna, ''Smilodon'' became extinct by 10,000 years ago in the [[Late Pleistocene extinctions|late Pleistocene extinction phases of North and South America]]. Its extinction has been linked to the decline and extinction of large herbivores. Hence, ''Smilodon'' could have been too specialized at hunting large prey and may have been unable to adapt.<ref name=forelimbs />  Indeed, by the [[Bølling–Allerød warming]] event and before the [[Younger Dryas]] cooling event, ''S. fatalis'' showed changes in cranial morphology that hint towards increased specialization in larger prey and/or evolution in response to competition with other carnivores.<ref>{{cite journal|last1=Meachen|first1=Julie A.|last2=O'Keefe|first2=F. Robin|last3=Sadleir|first3=Rudyard W.|year=2014|title=Evolution in the sabre-tooth cat, Smilodon fatalis, in response to Pleistocene climate change|journal=Journal of Evolutionary Biology|volume=27|issue=4|pages=714–723|doi=10.1111/jeb.12340|pmid=24779050 }}</ref> However, a 2012 study of ''Smilodon'' tooth wear found no evidence that they were limited by food resources.<ref name=desantis2012>{{cite journal |last1=DeSantis |first1=L. R. G. |last2=Schubert |first2=B. W. |last3=Scott |first3=J. R. |last4=Ungar |first4=P. S. |year=2012 |title=Implications of diet for the extinction of saber-toothed cats and American lions |journal=PLOS ONE |doi=10.1371/journal.pone.0052453 |bibcode=2012PLoSO...752453D |volume=7 |issue=12 |page=e52453 |pmid=23300674 |pmc=3530457|doi-access=free }} {{open access}}</ref> Other explanations include climate change and competition with ''[[Homo sapiens]]''<ref name=desantis2012 /> (who entered the Americas around the time ''Smilodon'' disappeared), or a combination of several factors, all of which apply to the general [[Late Pleistocene extinctions|Late Pleistocene extinction event]], rather than specifically to the extinction of the saber-toothed cats.{{Sfn|Antón|2013|pp=217–230}} One factor often cited here is the cooling in the [[Younger Dryas]], which may have drastically reduced the habitable space for many species. In terms of human influence, there is evidence of a fire-induced regime change in Rancho la Brea that preceded the [[Local extinction|extirpation]] of megafauna in the area, with humans most likely responsible for the increase in fire intensity.<ref name="fire">{{cite journal|last1=O'Keefe|first1=F. Robin|last2=Dunn|first2=Regan E.|last3=Weitzel|first3=Elic M.|last4=Waters|first4=Michael R.|last5=Martinez|first5=Lisa N.|last6=Binder|first6=Wendy J.|last7=Southon|first7=John R.|last8=Cohen|first8=Joshua E.|last9=Meachen|first9=Julie A.|last10=DeSantis|first10=Larisa R. G.|last11=Kirby|first11=Matthew E.|last12=Ghezzo|first12=Elena|last13=Coltrain|first13=Joan B.|last14=Fuller|first14=Benjamin T.|last15=Farrell|first15=Aisling B.|last16=Takuechi|first16=Gary T.|last17=MacDonald|first17=Glen|last18=Davis|first18=Edward B.|last19=Lindsey|first19=Emily L.|year=2023|title=Pre–Younger Dryas megafaunal extirpation at Rancho La Brea linked to fire-driven state shift|journal=Science|volume=381|issue=6659|pages=eabo3594 |doi=10.1126/science.abo3594|pmid=37590347 }}</ref>

Writers of the first half of the twentieth century theorized that the last saber-toothed cats, ''Smilodon'' and ''Homotherium'', became extinct through competition with the faster and more generalized felids that replaced them. It was even proposed that the saber-toothed predators were inferior to modern cats, as the ever-growing canines were thought to inhibit their owners from feeding properly. Since then, however, it has been shown that the diet of machairodontines such as ''Smilodon'' and ''Homotherium'' was diverse. They do not seem to have been limited to giant animals as prey, as suggested before, but fed on whatever was available, including [[Bovinae|bovines]], [[Equus (genus)|equines]] and [[Camelidae|camelids]].<ref>{{Cite journal |last=Bocherens |first=Hervé |date=2015-06-01 |title=Isotopic tracking of large carnivore palaeoecology in the mammoth steppe |url=https://www.sciencedirect.com/science/article/pii/S0277379115001250 |journal=Quaternary Science Reviews |volume=117 |pages=42–71 |doi=10.1016/j.quascirev.2015.03.018 |bibcode=2015QSRv..117...42B |issn=0277-3791}}</ref><ref>{{Cite journal |last1=Prevosti |first1=Francisco J. |last2=Martin |first2=Fabiana M. |date=2013-08-14 |title=Paleoecology of the mammalian predator guild of Southern Patagonia during the latest Pleistocene: Ecomorphology, stable isotopes, and taphonomy |url=https://www.sciencedirect.com/science/article/pii/S1040618213000049 |journal=Quaternary International |series=Ranked habitats and the process of human colonization of South America |volume=305 |pages=74–84 |doi=10.1016/j.quaint.2012.12.039 |bibcode=2013QuInt.305...74P |issn=1040-6182|hdl=11336/84524 |hdl-access=free }}</ref> Additionally, non-machairodontine felids such as the American lion and ''[[Miracinonyx]]'' also became extinct during the Late Pleistocene, and saber-toothed and conical toothed felids had formerly coexisted for more than a million years.{{sfn|Antón|2013|p=223}} The fact that saber-teeth evolved many times in unrelated lineages also attests to the success of this feature.{{Sfn|Antón|2013|pp=217–230}}

The youngest direct radiocarbon date for ''S. fatalis'' differs from that of ''S. populator'' by thousands of years, the former just before the Younger Dryas cooling event and the latter by the early Holocene.<ref name="book">{{cite book|last=Stuart|first=Anthony J.|title=Vanished Giants: The Lost World of the Ice Age|chapter=Chapter 6. North America: mastodon, ground sloths, and sabertooth cats|date=August 20, 2022 |publisher=University of Chicago Press|pages=67–112 |isbn=978-0-226-82403-1}}</ref> The latest ''S. populator'' specimen from the Jirau Paleontological Site has been dated to 8,189–9,079 years [[Radiocarbon calibration|cal.]] [[Before Present]] (BP),<ref>{{Cite journal |last1=Faria |first1=F. H. C. |last2=Carvalho |first2=I. S. |last3=Araújo-Júnior |first3=H. I. |last4=Ximenes |first4=C. L. |last5=Facincani |first5=E. M. |title=3,500 years BP: The last survival of the mammal megafauna in the Americas |year=2025 |journal=Journal of South American Earth Sciences |volume=153 |at=105367 |doi=10.1016/j.jsames.2025.105367 }}</ref> while the latest ''S. fatalis'' specimen recovered from the Rancho La Brea tar pits has been dated to 13,025 years ago.<ref>{{cite journal|last1=O'Keefe|first1=F.R.|last2=Fet|first2=E.V.|last3=Harris|first3=J.M.|title=Compilation, calibration, and synthesis of faunal and floral radiocarbon dates, Rancho La Brea, California|journal=Contributions in Science|volume=518|year=2009|pages=1–16|doi=10.5962/p.226783|s2cid=128107590|doi-access=free}}</ref> A specimen of ''S. fatalis'' from Iowa dates to 13,605–13,455 years [[Before Present]] (BP).<ref>{{Cite journal |last1=Hill |first1=Matthew G. |last2=Easterla |first2=David A. |date=May 2023 |title=A complete sabertooth cat cranium from the Midcontinent of North America and its evolutionary and ecological context |url=https://linkinghub.elsevier.com/retrieve/pii/S0277379123000938 |journal=Quaternary Science Reviews |language=en |volume=307 |pages=108045 |doi=10.1016/j.quascirev.2023.108045|bibcode=2023QSRv..30708045H |s2cid=257861663 }}</ref> ''Smilodon populator'' remains found in the cave of Cueva del Medio, near the town of Soria, northeast [[Última Esperanza Province]], [[Magallanes Region]] in southernmost [[Chile]] have been dated to 10,935–11,209 years ago.<ref>{{cite journal|doi=10.4067/S0716-078X2010000200010|title=New evidence of the sabertooth cat Smilodon (Carnivora: Machairodontinae) in the late Pleistocene of southern Chilean Patagonia|journal=Revista Chilena de Historia Natural|volume=83|issue=2|year=2010|last1=Prieto|first1=Alfredo|last2=Labarca|first2=Rafael|last3=Sierpe|first3=Víctor|doi-access=free}}</ref> The most recent credible carbon-14 date for ''S. fatalis'' has been given as 11,130 BP.<ref name="Fiedal">{{Cite book | first = Stuart | last = Fiedel | series = Vertebrate Paleobiology and Paleoanthropology | editor-last = Haynes | editor-first = Gary | contribution = Sudden Deaths: The Chronology of Terminal Pleistocene Megafaunal Extinction | contribution-url = https://link.springer.com/content/pdf/10.1007%2F978-1-4020-8793-6.pdf | title = American Megafaunal Extinctions at the End of the Pleistocene | year = 2009 | pages = 21–37 | publisher = [[Springer Science+Business Media|Springer]] | doi = 10.1007/978-1-4020-8793-6_2 | isbn = 978-1-4020-8792-9 }}</ref> However, such radiocarbon dates are likely uncalibrated, meaning that they were not adjusted from calendar years to regular years. As a result, the dates appear younger than they actually are. Therefore, the ''S. fatalis'' specimen from Rancho La Brea is the youngest-recorded of the species,<ref name="book"/> suggesting extinction before the Younger Dryas based on its last appearance in California as opposed to other regions where megafauna declined by the Younger Dryas.<ref name="fire"/>