02619nas a2200289 4500008004100000022001300041245006600054210006500120300000800185490000700193520182900200653001402029653002102043653002002064653001002084653001202094653001402106653001602120653001302136653001502149653002002164100002102184700002002205700001502225700002202240856006702262 2021 eng d a0960982200aDietary ecology of the scimitar-toothed cat Homotherium serum0 aDietary ecology of the scimitartoothed cat Homotherium serum a1-80 v313 a

The scimitar-toothed cat Homotherium was one of the most cosmopolitan cats of the Pleistocene, present throughout Eurasia, Africa, and the Americas until at least ~28 thousand years ago. Friesenhahn Cave (Bexar County, Texas) contains some of the best-preserved specimens of Homotherium serum alongside an abundance of juvenile mammoths, leading some to argue that H. serum preferentially hunted juvenile mammoths.Dietary data of Homotherium are rare, with their ecology inferred from morphological, taphonomic, and genetic data. Here, we use a multi-proxy approach to clarify the dietary ecology of H. serum as compared to extinct and extant cats and their relatives. Dental microwear texture analysis (DMTA) reveals that H. serum consumed soft and tough foods, similar to the extant cheetah, which actively avoids bone, but in stark contrast to extant lions and hyenas, which are observed to engage in durophagy (i.e., bone processing). DMTA data are consistent with taphonomic evidence of bone defleshing and the absence of bone-crunching behavior in H. serum. Stable carbon isotope values of H. serum indicate a clear preference for C4 grazers including juvenile mammoths, in agreement with taphonomic evidence suggestive of a Homotherium den and morphological data indicative of a relatively cursorial lifestyle. Notably, the inferred diet of H. serum contrasts with the extinct dirk-tooth sabertooth cat Smilodon fatalis, which preferred forest/woodland prey and engaged in bone processing. Homotherium serum exhibited a novel combination of morphological adaptations for acquiring open-country prey, consuming their soft and tough flesh—including the tough flesh of juvenile mammoths.

10acarnivore10adental microwear10adietary ecology10afelid10amammoth10aMammuthus10aPleistocene10aPredator10asabertooth10aStable isotopes1 aDeSantis, L.R.G.1 aFeranec, R., S.1 aAntón, M.1 aLundelius, E., L. uhttps://linkinghub.elsevier.com/retrieve/pii/S096098222100434602682nas a2200349 4500008004100000022001300041245010600054210006900160260001200229300001900241490000700260520164700267653001001914653001401924653002101938653000901959653001201968653001701980653001601997653001902013653001302032653002002045100002702065700002502092700002002117700002002137700002502157700002102182700002302203700002302226856008302249 2019 eng d a0960982200aCauses and Consequences of Pleistocene Megafaunal Extinctions as Revealed from Rancho La Brea Mammals0 aCauses and Consequences of Pleistocene Megafaunal Extinctions as c08/2019 a2488 - 2495.e20 v293 a

The fossils preserved in the Rancho La Brea “tar” seeps in southern California span the past ∼50,000 years and provide a rare opportunity to assess the ecology of predators (e.g., the American lion, sabertooth cats, cougars, dire wolves, gray wolves, and coyotes), including clarifying the causes and consequences of the terminal Pleistocene extinction event. Here, a multi-proxy approach elucidates dietary responses of carnivorans to changing climates and megafaunal extinctions. Using sample sizes that are unavailable anywhere else in the world, including hundreds of carnivoran and herbivore specimens, we clarify the paleobiology of the extinct sabertooth cats and dire wolves—overturning the idea that they heavily competed for similar prey. Canids (especially the dire wolf) consumed prey from more open environments than felids, demonstrating minimal competition for prey throughout the latest Pleistocene and largely irrespective of changing climates, including just prior to their extinction. Coyotes experienced a dramatic shift in dietary behavior toward increased carcass utilization and the consumption of forest resources (prey and/or plant resources) after the terminal Pleistocene megafaunal extinction. Extant predators’ ability to effectively hunt smaller prey and/or utilize carcasses may have been a key to their survival, especially after a significant reduction in megafaunal prey resources. Collectively, these data suggest that dietary niches of carnivorans are not always static and can instead be substantially affected by the removal of top predators and abundant prey resources.

10aCanis10aCarnivora10adental microwear10aDiet10amammals10apaleoecology10aPleistocene10aRancho La Brea10aSmilodon10aStable isotopes1 aDeSantis, Larisa, R.G.1 aCrites, Jonathan, M.1 aFeranec, R., S.1 aFox-Dobbs, Kena1 aFarrell, Aisling, B.1 aHarris, John, M.1 aTakeuchi, Gary, T.1 aCerling, Thure, E. uhttps://www.sciencedirect.com/science/article/pii/S0960982219307869?via%3Dihub