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Excavations associated with wastewater treatment facilities in the Santiago Basin of Chile uncovered remains of an adult male Stegomastodon platensis in Pleistocene fluvial sediments. The specimen included a skull with both tusks still in their alveoli. A small sample block of dentin and cementum was excised from the right tusk for analysis of compositional and structural variation recorded in the sequence of dentin layers. The sample was analyzed using serial isotope assays, microCT, and measurement of dentin increments in thin sections. These procedures allowed us to recover life history information relating to the final four years of life. Analyses show seasonal variation in composition, density, and growth rate, permitting identification of years. MicroCT features appear to recur semiannually, which has not been observed previously in proboscidean tusks; these features are interpreted to correspond to the winter-spring boundary and some other aspect of environment or behavior recurring within each year. Average annual apposition of dentin within the tusk is 10.4 mm for complete years studied, suggesting that this individual was healthy leading up to the final year of life. Recurrent periods of low rate of apposition measured in weekly dentin increments that formed during the summer are interpreted as representing periods of musth. Using the location of microCT features, annual appositional thickness, and the pattern of weekly growth within the final year of life, we interpret the season of death for this individual as being within the early autumn.

The site Los Notros, located just 60 m west of the site Pilauco in Osorno (Chile), was discovered in 2008, with excavations beginning in April 2016. The geology of Los Notros is similar to that of the Pilauco site where strata LN-1 and LN-2 are equivalent to layers PB-7 and PB-8 from Pilauco. However, Los Notros includes an additional stratum (LN-3) of prominent black color, finer texture, and similar age as the discordance between PB-8/PB-9, whereas layer LN-4 is equivalent to PB-9. Additionally, a chronostratigraphic relationship between both sites is suggested based on concordant radiocarbon ages. Excavations at the Los Notros have provided 15 fossil specimens from layers LN-1 and LN-2, 11 of which were taxonomically determined at least up to order level. A rich dental record represents the families Equidae, Gomphotheriidae, and Cervidae, whereas a nearly complete gomphothere tusk lacking torsion and enamel strips allowed its assignment to Notiomastodon platensis. Thus, the presence of N. platensis in northern Patagonia—the southern limit of the species range—is confirmed together with the identification of Equus (A.) sp., and the extension of the distributional range for the extinct genus Antifer from Cervidae.

Pilauco shows two distinct layers containing remains of Pleistocene mammals (PB-7 and PB-8). The site is spatially divided into two sectors, East (45 m2) and West (27 m2). The current study is centered in the Western sector, where the majority of the materials come from layer PB-7 (%NISP = 92.5). Overall, this layer does not show signs of weathering, exhibiting instead trampling marks, and in a lesser quantity, large carnivore tooth marks. The fragmentation level is low, particularly for the fossils of Gomphotheriidae, for which most of the fractures occurred when the fossils were not fresh. No human marks of any kind were identified. The impact of these distinct factors in the formation of the record of PB-7 was evaluated using the available data and concluded in an in situ death of a gomphothere, to which would have been added anatomical elements of other taxa, redeposited coluvially and/or through vertical migration as a result of trampling. Carnivores would have been primarily responsible for the alteration and possibly subtraction of skeletal remains; as of now there is no evidence of human impact in this process. The materials recovered in PB-8 layer could also have been deposited by colluvial processes, although the sample is very small to discuss the taphonomic processes that have occurred in this layer.

This chapter synthesizes the findings of fossil remains from equids and camelids at the Pilauco site, including the first discoveries from 1986, as well as the systematic excavations since 2007. The group of horses is exclusively represented by the genus Equus, as was identified on cranial and postcranial remnants. The findings from the eastern and western sectors display metric differences that might be indicative for the presence of two species or morphotypes. The horse remains are most abundant in stratigraphic layer PB-8. The metric analysis assigns most of the camelid remnants to cf. Hemiauhenia paradoxa, whereas the remaining, less diagnostic, material is classified merely on the family level. The camelid remnants have been recovered from stratigraphic layers PB-7 and PB-8. Based on the distribution of camelid and equid fossils, two occupational events can be spatially distinguished within layer PB-7. A preliminary taphonomic analysis indicates some differences in the depositional history between the eastern and western sector of the site.

Rallidae, which includes coots, crakes and moorhens, is one of the most speciose families among the Gruiformes. This family exhibits a pattern of diversification that has involved significant episodes of regional expansion and speciation resulting in the presence of members of this group in every continent with the exception of Antarctica. In this work, we describe the diversity of fossil rallids from late Pleistocene-early Holocene deposits of the Laguna de Tagua Tagua Formation located in central Chile. We report the presence of the extant taxa, Fulica armillata, Fulica rufifrons, Fulica cf. F. rufifrons, Fulica cf. F. ardesiaca and Pardirallus sanguinolentus, and also identify a large new extinct coot, Fulica montanei sp. nov. represented by three left tarsometatarsi. Fulica montanei corresponds to the first extinct rallid recorded in the Quaternary of South America. The most remarkable feature of the tarsometatarsus of Fulica montanei is their large size, which falls in the range of the extant Andean species Fulica cornuta and the extinct Fulica prisca from New Zealand. An autapomorphic combination of characters observed in the tarsometatarsi also supports the erection of a new species. These rails coexisted with extinct megafauna, as well as small and medium-sized vertebrates and, presumably, with humans, constituting a faunal assemblage with no analogous today. Fulica montanei probably became extinct during the late Pleistocene-early Holocene.

Objective Re-evaluate the pathological lesions found on a gomphothere recovered from Quebrada Quereo (Late Pleistocene), Coquimbo region, Chile (31o55'41” S, 71o34'43” W, 20 masl). Materials 227 axial and appendicular specimens from a young adult male individual (SGO.PV.267). Methods Macroscopic and radiographic analysis. Results Pathological conditions identified included asymmetries of a cervical vertebra and of thoracic vertebra 16, degenerative joint disease in thoracic and lumbar vertebrae, possible evidence of neoplastic lesions within the bodies of three thoracic vertebrae (possibly hemangiomas), and fusion at thoracic vertebrae 15 and 16, suggesting the presence of spondyloarthropathy. Conclusions The original diagnosis of traumatic lesions on this specimen is unsupported. The re-evaluation identified the presence of developmental defects, degenerative joint disease, possible neoplastic lesions, and spondyloartropathy. Significance The present analysis adds data to the sparse paleopathological record of South American gomphotheres. Limitations Taphonomic alteration of some skeletal elements, as well as the presence of an incomplete individual, limits the ability to determine the etiology of some of the lesions identified. Suggestions for further research Researchers are encouraged to re-examine specimens curated in museums in order to identify pathological conditions that might have been overlooked or might benefit from re-evaluation.

Proboscideans are so-called ecosystem engineers and are considered key players in hypotheses about Late Pleistocene megafaunal extinctions. However, knowledge about the autoecology and chronology of the proboscideans in South America is still open to debate and raises controversial views. Here, we used a range of multiproxy approaches and new radiocarbon datings to study the autoecology of Chilean gomphotheres, the only group of proboscideans to reach South America during the Great American Biotic Interchange (∼3.1 to 2.7 million years before present). As part of this study, we analyzed stable isotopes, dental microwear, and dental calculus microfossils on gomphothere molars from 30 Late Pleistocene sites (31° to 42°S). These proxies provided different scales of temporal resolution, which were then combined to assess the dietary and habitat patterns of these proboscideans. The multiproxy study suggests that most foraging took place in relatively closed environments. In Central Chile, there is a positive correlation between lower δ13C values and an increasing consumption of arboreal/scrub elements. Analyses of dental microwear and calculus microfossils have verified these leaf-browsing feeding habits. From a comparative perspective, the dietary pattern of South American gomphotheres appears to be constrained more by resource availability than by the potential dietary range of the individual taxa. This multiproxy study is aimed at increasing knowledge of the life history of gomphotheres and thus follows an issue considered one of the greatest challenges for paleontology in South America, recently pointed out by the need to thoroughly understand the role of ecological engineers before making predictions about the consequences of ecosystem defaunation.

Studies on South American Gomphotheriidae started around 210 years ago and, 150 years later, the classic study “The mastodonts of Brazil” by Simpson and Paula Couto (1957) attempted to clarify the complex issues related to our understanding of these proboscideans. Here, we update state of knowledge regarding proboscideans in South America subsequent to the publication of Simpson and Paula Couto (1957). The taxonomy of South American proboscideans is now stable and two species are recognized, Notiomastodon platensis and Cuvieronius hyodon. The former had a wide distribution in South America (from lowlands to highlands and from east to west coasts), while the latter was restricted to Ecuador, Peru and Bolivia. Although records of Notiomastodon are abundant and occur in almost overlapping geographic distribution with Cuvieronius, they have never been recorded in the same locality. Here, we evaluated over 500 South American localities with proboscidean remains, although only cranial and dental specimens show recognizable diagnostic features. As both proboscideans in South America had a generalist-opportunist alimentary strategy, a competitive exclusion probably precluded their sympatry. Their origin is most probably related to independent migrations from Central America during the Great American Biotic Interchange. They are not sister-taxa – Cuvieronius hyodon is sister-taxon of Rhynchotherium, and this clade is closer to Notiomastodon platensis than to the other proboscideans, supporting the hypothesis of independent origins. Notiomastodon platensis has a continuous record from the Early Pleistocene to Early Holocene, when it became extinct, probably due to synergy of human impact and climatic changes during the Pleistocene/Holocene transition. In contrast, extinction of Cuvieronius hyodon happened much earlier, and it was not related to the terminal Pleistocene event that lead the extinction of selected megafauna in South America, including Notiomastodon., Facultad de Ciencias Naturales y Museo

The archaeo-paleontological site of Pilauco (southern Chile) has one of the richest Late Pleistocene mammal records of the northern Chilean Patagonia, with at least nine forms dominated by gomphothere remains. This site has a complex taphonomic history due to postdepositional processes that affected the integrity, frequency, and distribution of the fossil bones. One of these processes is the action of large carnivores, indicated by tooth marks recorded exclusively in gomphothere bones. In this paper, we describe Gomphotheriidae fossil remains and give a detailed description of carnivore tooth marks detected in the sample. The absence of diagnostic fossil specimens does not allow genus or species assignment. The type, location, intensity, and dimensions of the tooth marks are compatible at least with a large felid, which probably scavenged a partially exposed carcass. The record of this taphonomic feature is important in order to understand the postdepositacional history of the Pilauco site, in which natural and cultural agents are involved.

We present a preliminary description and taxonomic assignment of the Lamini fossil remains recovered from the paleontological site of Pilauco (late Pleistocene) in southern Chile. Based on metric variables the fossils are temporarily asigned to cf. Hemiauchenia paradoxa Gervais & Ameghino 1880, waiting for new and more diagnostic remains. We present and discuss some taphonomic processes occurring within the site, starting from the study of the marks observed in the surface of the fossils, wich are consistent with the bog environment with occasional fluvial flooding described for the site.Se presenta la descripción y asignación taxonómica preliminar de los restos de Lamini recuperados en el sitio paleontológico de Pilauco (Pleistoceno tardío) ubicado en el sur de Chile. Sobre la base de variables métricas los materiales son provisoriamente incluidos en cf. Hemiauchenia paradoxa Gervais & Ameghino 1880 a la espera de materiales más diagnósticos. Se discuten algunos procesos tafonómicos ocurridos al interior del yacimiento a partir del estudio de las marcas registradas en la superficie de los fósiles, las que son concordantes con el ambiente palustre con inundaciones esporádicas fluviales descrito para el sitio.

There is an abundant fossil record of the family Gomphotheriidae in Chile, which is en- tirely ascribed to the late Pleistocene. Despite this, the lack of taxonomically diagnostic material has lead to an extended discussion, which has not reached a consensus regarding the number of forms of gomphotheres effectively present. This paper discusses the taxonomy of Chilean gomphotheres, based on tooth morphology and biometry, paleoecological and biogeographical data. The morphol- ogy of the tusks indicates the presence of the Stegomastodon genus in Chile, while bivariate and multivariate analyses of the teeth show an important amount of variability within the studied sample, although with a tendency towards larger sizes for the genus Stegomastodon and the Chilean samples than for Cuvieronius, especially among the M3s and m3s. In spite of this, in this paper only the specimens from localities that yielded molars associated with tusks are assigned to the genus Stego­ mastodon. Biogeographic information is consistent with the presence of a lowland-adapted taxon such as Stegomastodon, which could have reached the Chilean territory either through an Andean corridor from Argentina, or through a low-altitude route from Peru, then by the northern region of Chile. Bibliographic isotopic data also indicates an adaptative change to C3 feeding along a latitudi- nal gradient, around 35-41oS, which makes the Chilean and south Argentinean results quite similar at these latitudes. Due to the metric variability observed, the Chilean samples could not be assigned to individual species.

Se presenta un análisis osteométrico uni y multivariado con los materiales fósiles -principalmente huesos cortos y falanges- de Vicugna sp. del yacimiento Cueva Lago Sofía 4 (13500 – 11000 AP), ubicado en la provincia de Última Esperanza (Región de Magallanes, Chile). Los resultados indican que los elementos analizados poseen un tamaño compatible con los registrados para Vicugna vicugna, no superando en ningún caso a los especímenes conocidos para Vicugna gracilis del Pleistoceno de la región Pampeana. Esto confirma la información morfológica y de ADN antiguo que indicaba la presencia de Vicugna vicugna en la Patagonia meridional chilena. Se discuten los resultados en términos taxonómicos, biogeográficos y paleoecológicos sugiriendo que la presencia de este taxón fuera de su rango actual de distribución se debió a las condiciones ambientales compartidas entre la Puna y Patagonia austral durante la transición Pleistoceno-Holoceno. La extinción de V. vicugna se habría debido al impacto de los cambios climáticos ocurridos al inicio del Holoceno producto de su dieta pastadora y etología no migratoria y territorial, a lo que se habría sumado una caza por parte de depredadores humanos y no humanos.

Se presenta una detallada descripcion de los osteodermos de armadillos recuperados en el cementerio Caleta Huelen 20 (Formativo Tardio), emplazado al sur de la desembocadura del rio Loa. A partir de los atributos morfologicos y metricos de las placas moviles de la muestra, los materiales son asignados a Chaetophractus vellerosus . Su presencia en el sitio, fuera de su rango de distribucion actual, debe ser entendida dentro de una extensa red de intercambios y movilidad que conecto el sector costero y la puna andina, la que se expresa con intensidad durante el periodo Formativo. Palabras claves: dasipodidos - armadillo - contextos funerarios - periodo Formativo - redes de intercambio - movilidad. Abstract In this paper, we present a detailed description of armadillo osteoderms recovered in the Caleta Huelen 20 cemetery (Late Formative), located at the mouth of Loa river. Based on studies of morphological and metric attributes of the carapace mobile bands, the materials are assigned to Chaetophractus vellerosus . Its presence at the site, beyond its present day distribution, must be understood within an extensive network of exchange and mobility that connected the coastal area and the Andean Puna, which intensified during the Formative period. Key words: Dasipodidae - armadillo - funerary context - Formative period-exchange networks- mobility.

During the late Pliocene, development of the Panama isthmus allowed North American cervids to expand their distribution to South America (Woodburne et al., 2006). At least eight cervid genera have ...

Paleontological and archaeological sites have frequently been found in open locations of the Intermediate Depression of south-central Chile. This paper presents the results of two field sampling seasons carried out at the Pilauco Site (ca. 39°S) and compares them with those of three well known sites in Chile: Quereo, Tagua-Tagua and Monte Verde, ca. 32°, 34° and 41°S, respectively. Stratigraphic data collected at Pilauco and the resulting radiocarbon age model suggest that before 12,540 ± 90 BP the old Damas River eroded an older volcaniclastic hill, which was followed by a bog formation in an ox-bow lake. The site was developing up to 11,004 ± 186 BP, the date of the youngest vertebrate fossil. Two younger peat beds seal the site. As in Tagua-Tagua and Monte Verde, Gomphotheres are the most represented megafauna. Fossils of Equidae, Camelidae, Cervidae, Mephitidae, Muridae, Myocastoridae and Xenarthra are also found in Pilauco. As a whole, 718 bones, 30 teeth and 11 coprolites represent the extinct and extant vertebrates. Preliminary taphonomic results suggest action of various agents in the bones, i.e. trampling, root etching, abrasion, and carnivore gnawing. The spatial analysis suggests the transfer of smaller anatomical units (e.g. bones of camelids and horses) and the rearrangement of some pieces comparatively large (e.g. gomphothere bones). Similar to the present day north Patagonian landscape, the area where Pilauco site is located had a variety of animal resources, plants and stones in an ecotone between hills, floodplains and wetlands. A total of 101 lithics were recorded: basalt and quartzite were collected from nearby fluvial deposits and dacitic obsidian from the local volcaniclastic deposits. Debitage is the most represented lithic item (75%); cores and marginal edge-trimmed artifacts represented 12 and 13%, respectively. Artifacts and flakes are spatially and temporality associated in the same PB-7 bed with high bone concentrations in some specific areas, between 361 and 424 cm of local altitude. This industry is characterized by a recurrent lithic expedite technology with production of flakes and chips which mastered marginal retouches over the bifacial trimming. This seems to be connected to strategic conditions of high resource diversity, especially of human groups with a high or medium mobility across land. Pilauco represents a site contemporaneous to Monte Verde related as well to the first human occupation in the southern cone of South America, but with higher mammal diversity.

El presente trabajo discute el estatus taxonomico de la especie Antifer niemeyeri Casamiquela, 1984, definida a partir de astas completas procedentes de la laguna Taguatagua y la quebrada de Quereo (Pleistoceno tardio-Holoceno temprano), en Chile central (30-35°S). Se concluye, a partir de un estudio morfologico y morfometrico detallado, que Antifer niemeyeri debe ser considerado sinonimo de Antifer ultra Ameghino, 1889 dados los caracteres anatomicos compartidos con esta especie. Los resultados amplian la distribucion geografica del taxon, que previamente se registraba en Argentina, Uruguay y sur de Brasil, y confirman su biocron para el Pleistoceno tardio-Holoceno temprano (edad Lujanense), aun cuando las fechas radiocarbonicas de Chile central (ca. 9.900 anos 14C AP) corresponden a las mas tardias para la especie. A la luz de la evidencia paleoclimatica disponible, se vincula A. ultra durante el Pleistoceno de Chile central a ambientes calidos y abiertos. Considerando estos requerimientos, se discute su posible via de ingreso al actual territorio chileno a traves de corredores ubicados hacia el sur del macizo andino, y su coexistencia con Hippocamelus bisulcus Molina, 1782. De acuerdo a la informacion estratigrafica y paleoambiental, se postula que ambas especies habrian sido alopatridas, por lo menos en el area de estudio.

Newly described outcrops, excavations and sediment cores from the region of Ultima Esperanza, Magallanes, contain tephra derived from the large late-glacial explosive R1 eruption of the Reclus volcano in the Andean Austral Volcanic Zone. New radiocarbon dates associated to these deposits refine previous estimates of the age, to 14.9 cal kyrs BP (12,670±240 14C yrs BP), and volume, to >5 km3, of this tephra. The geographic and stratigraphic distribution of R1 also place constraints on the evolution of the ice-dammed proglacial lake that existed east of the cordillera in this area between the termination of the Last Glacial Maximum (LGM) and the Holocene. This proglacial lake generated wavecut terraces, and also caves, such as the Cueva de Milodon, along the highest prominent terrace. The current elevation of these terraces depends on the total amount of post-glacial isostatic rebound, which is unknown. Due to differential rebound, the highest prominent lake terraces decrease in height from west-to-east, from ~170 m a.s.l. on Peninsula Antonio Varas west of Seno Ultima Esperanza, to ~150 m a.s.l. around Lago Sofia, and down to ~125 m a.s.l. along their easternmost margin. The presence of thick deposits of R1 tephra in some of the caves around Lago Sofia implies that the proglacial lake had already dropped below its highest level prior to the time of this eruption, and, in fact, even earlier, prior to 16.1 cal kyrs BP (13,560±180 14C yrs BP), when land mammals first occupied these caves. The depositional environment of R1 in a core from Dumestre bog suggests that the lake level was in fact 70 m a.s.l. until 12.8 cal kyrs BP (10,695±40 14C yrs BP). However, a 14.2 cal kyrs BP (12,125±85 14C yrs BP) Mylodon pelvis from a nearby site, located at only ~7 m a.s.l., suggests that the lake could have emptied, for at least a brief period, to this low level at this time. This latter datum, combined with the lack of any prominent terraces between the highest ones (170-125 m a.s.l.) and much lower ones (at only 30 m a.s.l. on Peninsula Antonio Varas and 20 m a.s.l. along the coast north and south of Puerto Natales), suggests abrupt changes in the lake level after the R1 eruption. The likely mechanism for producing these changes in Ultima Esperanza was the catastrophic failure and subsequent re-sealing of an ice dam in Paso Kirke, the only below sea-level pathway west to the Pacific north of Fjordo Obstruccion. The final stage of lake drainage, from the lower terrace level (20-30 m a.s.l.) occurred at 10.3 cal kyrs BP.

Surpatagonia es particularmente rica en mamiferos finiplesitocenos, particularmente camelidos, equidos y xenartros. Los carnivoros, por su parte, se encuentran representados en menor numero en el registro paleontologico. Dentro de estos, el genero Smilodon, es de particular interes debido a que su presencia en la region no ha sido convincentemente demostrada. En este trabajo presentamos evidencia dental que permite confirmar la presencia de Smilodon populator (Lund) en la region. Esta evidencia corresponde al registro mas sureno de este taxon y al paso final en la colonizacion de America del Sur despues del Gran Intercambio Biotico Americano. Un fechado radiocarbonico directo AMS indica que los restos de Patagonia del Sur corresponden a los registros mas tardios para este genero en el subcontinente.

Este trabajo entrega los resultados de los análisis taxonómicos y tafonómicos efectuados a los conjuntos faunísticos de las capas más profundas del sitio cueva Las Guanacas (Región de Aisén). Se constata la presencia de ocho taxones mayores, cuatro de ellos extintos (Mylodon darwini Owen, Macrauchenia patachonica Owen, Hippidion saídiasi Roth y Camelidae indet.) y cuatro que aún habitan el sector o sus alrededores (Hippocamelus bisulcus Molina, Pudú pudú Molina, Lama guanicoe Müller y Dusicyon culpaeus Molina). La evidencia tafonómica descarta una ocupación cultural temprana, apuntando en cambio a una utilización natural de la cueva por una o más especies adicionales, reconocibles a partir de distintas líneas de evidencia (etología de los predadores finipleistocénicos, taxones presentes, frecuencia de partes esqueletarias, modificaciones naturales). Se plantea que el principal agente responsable de la formación del conjunto faunístico de Las Guanacas habría sido un carnívoro (al menos un felino de tamaño medio, posiblemente Panthera onca Linnaeus), el que habría implementado distintas estrategias de obtención de las carcasas (caza y carroñeo) hacia los 13.200 AP.