Bears of the Pleistocene

[brotherbear]

https://www.researchgate.net/publication...onia_Chile 
 
The southernmost bear: Pararctotherium (Carnivora, Ursidae, Tremarctinae) in the latest Pleistocene of Southern Patagonia, Chile.  
A second upper incisor belonging to the tremarctine bear Pararc-totherium was recovered from latest Pleistocene deposits in Cueva de los Chingues, Magallanes, Chile (San Roman et al., 2000; Fig. 1). This is the southernmost record of an ursid in the world and one of the youngest records of Pararctotherium. The paleoenvironment of south-ern Patagonia in the latest Pleistocene (ca. 11,000 yBP) was a cold grassland. The Ursidae originated during the late Eocene in the Holarctic region and throughout its history has primarily been restricted to the Northern Hemisphere. Ursids twice dispersed into Africa (Hunt, 1996): the Hem-icyoninae in the early Miocene and Agriotherium in the late Miocene, with the latter reaching the southern tip of Africa (ca. 33Њ 43Ј S). The Tremarctinae is comprised of five genera: Plionarctos, consid-ered Pararctotherium to be a subgenus of Arctotherium. We regard both Arctotherium and Pararctotherium as valid, distinct genera based on the systematic and phylogenetic revision of South American fossil bears by LHS (e.g., Soibelzon, 2000, 2002; Soibelzon et al., 2000). Tremarctines dispersed into South America from North America at least twice. The oldest records of Arctotherium are early Pleistocene (Ensenadan age; Kraglievich and Ameghino, 1940; Berman, 1994; Soi-belzon and Bond, 1998; Soibelzon et al., 2001; Soibelzon, 2002). Tre-marctos, which lacks a fossil record in South America, probably crossed the Panamanian Isthmus in the latest Pleistocene or Holocene (Soibel-zon, 2002). South American fossil bears are primarily recovered from the Pampean Region (ca. 33Њ S), with isolated finds in Brazil, Bolivia, Chile, Venezuela, and Uruguay. Arctotherium latidens is the lone En-senadan tremarctine in South America. Following its extinction, tre-marctines were represented by several species of Pararctotherium dur-ing the middle to late Pleistocene (Bonaerian and Lujanian ages; Cione and Tonni, 1999). It was distributed widely across southern South America (Bolivia, Brazil, Argentina, Uruguay, and Chile) and persisted until the end of the Lujanian (Soibelzon and Bond, 1998; Soibelzon, 2002).
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