Fossil rodents in Mylodon Cave as indicators of late Pleistocene–Holocene environmental evolution in southern Chile

Abstract

We conducted the first taphonomic and paleoenvironmental study based on late Pleistocene–Holocene small mammal remains recovered from the famous Mylodon Cave (Cerro Benítez area, Última Esperanza, Chile). Most of the analyzed material came from the extensive excavations made by Earl Saxon in 1976. We also studied late Holocene small mammal samples of the neighboring rock shelter Dos Herraduras 1. Analyzed remains were mostly produced by owls, probably living inside the caves. In Mylodon Cave, the higher values of girdle bones are consistent with a windblown litter. We recorded nine species of rodents, seven cricetids, and two caviomorphs; almost all the identified taxa integrate recent local communities. Late Pleistocene–Holocene assemblages are characterized by the chinchilla rat Euneomys, indicating unforested areas around the caves under cold and moist climatic conditions. Middle Holocene amelioration is reflected by incremental rodent species richness, including the first record of taxa clearly associated with forest (e.g., Abrothrix lanosa). Late Holocene assemblages are markedly stable, indicating local conditions similar to the current (historical) environment. Quaternary rodents from Cerro Benítez area do not indicate abrupt environmental changes during middle–late Holocene, but a progressive trend towards forest increase.

Geomorphology and sedimentology of the Cerro Benítez of the cavities (Patagonia, Chile): genesis and evolution of a megafauna sedimentary trap during the last glaciation

“…Dans le sillage des analyses de pollens et restes macroscopiques de végétaux réalisées depuis la seconde moitié du vingtième siècle (Salmi, 1955 ;Moore, 1978 ;Markgraf, 1985 ;Heusser et al, 1992 ;van Geel et al, 2022), un nombre croissant de marqueurs paléoenvironnementaux tels que les assemblages de rongeurs (Pardiñas et al, 2021) (Jaillet et al, 2008 ;Maire et al, 2009), ayant notamment conduit à la découverte de grottes occupées par l'Homme durant l'Holocène (Maire et al, 2009). Sur la façade atlantique semi-aride, les cavités pseudokarstiques du champ de lave de Pali Aike, situées à 52°S de latitude, dont la Cueva Fell et la Cueva Pali Aike, initialement fouillées par Bird (1938), ont récemment fait l'objet d'une réinterprétation taphonomique par Martin (2022).…”

“…BP (Martin et al, 2013), témoigne également d'un climat froid, avec un gel saisonnier atteignant une profondeur supérieure à 100 cm. Ces résultats concordent avec l'analyse des pollens et restes macroscopiques de végétaux contenus dans les coprolithes de Mylodon (Salmi, 1955 ;Moore, 1978 ;Markgraf, 1985 ;Heusser et al, 1992 ;van Geel et al, 2022) (Pardiñas et al, 2021).…”

Cambios en Las Comunidades De Micromamíferos Durante El Holoceno Tardío–antropoceno en El Sudeste De La Provincia De Buenos Aires (Argentina)

“…La aplicación exitosa de estos métodos en yacimientos boreales contrasta con su escasa resolución en Argentina central. Tanto como se ha discutido para con otras aproximaciones de uso foráneo, como es el caso del índice taxonómico de hábitat (véase Pardiñas et al, 2022), un abordaje regional usando las mismas requiere de ajustes específicos. Transplantar enfoques, aunque deseable en el paradigma de una ciencia globalizada, no es sinónimo de obtener resultados superadores.…”

Forest stability during the Holocene in Santa Catarina, southern Brazil revealed by small mammals from Gruta do Presépio

“…Small mammals are suitable proxies for paleoenvironmental and, to a minor extent, paleoclimatic reconstructions, particularly during the Quaternary (e.g. Andrews, 1990;Avery, 1982;Guillermo et al, 2021;Hadly, 1996;Pardiñas et al, 2022;Thackeray, 1987;Wood and Barnosky, 1994). Taphonomic studies of micromammal remains are important for inferring the main sources of the faunal accumulation, embracing a variety of agents and processes, in order to perform supported reconstructions of the past (e.g.…”