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The Cueva del Milodón (CdM, southern Chile), has been explored repeatedly since the end of the 19th century. Many institutions in the world house specimens from CdM, standing out the mylodontid sloths. Until now, 36 14C measurements were performed on these remains using equivalent methodologies, Gas Proportional Counter (GPC), Liquid Scintillation Counting (LSC) and Accelerator Mass Spectrometry (AMS). The goals of this work are to review published dates, report two new radiocarbon dates made by us, and discuss the occurrence of the mylodonts in southernmost South America in a glacial context and its possible coexistence with humans. Among the published 16 direct (hair, skin, bone) and 20 indirect (excrement) 14C dates, 13 and 18 are considered here as reliable, respectively. Dates considered unreliable presented several issues (transcription errors, duplicate dates, misidentified samples, etc.), being excluded from the analysis to avoid further misunderstandings. Two new 14C dates performed by us on pieces housed in the Museo de La Plata (skin - AMS) and (bone - LSC) were added, making a total of 33 valid dates. A remarkable amplitude in the radiocarbon ages of the mylodont remains in CdM is evidenced, showing a range of values from ∼14,000 BP to ∼9800 BP, since upper Pleistocene ("Tarantian") to early Holocene (Greenlandian). However, the direct dates of maximum confidence available show a strong modal representation in the Upper Pleistocene. Climate evidence available for this period indicates a complex interplay of deglaciation and brief cold reversals, but suggests that mylodonts could take advantage of their dense fur and thick skin, large body mass and suitability to live in caves to prosper in such cold and humid environments. Finally, evidence supporting coexistence of mylodonts and humans is briefly discussed. Image 1 • Mylodontid ground sloth mummified skin from Cueva del Milodón, Chile, was analized. • Two new radiocarbonic dates were performed on this remain. • Previous dates of ground sloth remains from the same place were reviewed. • More reliable dates suggest ground sloth presence around upper Pleistocene. • Paleoclimatic context was reviewed, as well as potential coexistence with humans. [ABSTRACT FROM AUTHOR]

We examine three avian remains from the Última Esperanza cave complex. This site is a Natural Monument situated along the flanks of Cerro Benítez, Magallanes Region of Chile. A tarsometatarsus (MLP 94-VIII-10-12) is assigned to Rhea pennata, and a humerus (MLP 94-VIII-10-111) to Phalacrocorax brasilianus. Both, R. pennata and P. brasilianu s, are currently distributed in the Magallanes Region, and their presence within the cave can be easily explained by the cut marks found on the tarsometatarsus, that evidence human consumption. The absence of traces on the humerus is not decisive in this regard, because the wings are not the most fleshy parts of the body and therefore, not the preferred piece by predators. It can represent the waste. A small bill (MLP 94-VIII-10-140) of a passerine bird belongs to a fresh bone and should be treated as contamination. • This contribution presents the first study of the Cueva del Milodón avian fossil record. • A humerus assigned to Phalacrocorax brasilianus and a tarsometatarsus of Rhea pennata, belong to species that occur in the area today. • The cut marks observed in Rhea pennata evidence anthropic interaction. • A bill from Cueva del Milodón belongs to a recent passerine bird and is considered contamination. [ABSTRACT FROM AUTHOR]