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During the Formative period by the Late-Holocene (ca. 3000–1500 BP), semi-sedentary and sedentary human occupations had emerged in the oases, salares, and riverine systems in the central depression (2400–1000 masl) of the Atacama Desert, northern Chile (19–25°S). This hyperarid core was marginally occupied during the post-Pleistocene and middle Holocene droughts. Settlement on these lower belts was accompanied by a rise in humidity, the introduction of Andean crops, flourishment of Prosopis spp. (algarrobo) forests, and increasing integration of domestic camelid caravans. Here, we explore lowland husbandry within risk-spreading strategies, focusing on silvopastoralism and endozoochory between camelids and algarrobos. Analysis of camelid coprolites from seven archeological sites located in the Pampa del Tamarugal, Loa River, and Salar de Atacama found intense grinding from camelid chewing and indicated a ruminal digestive system. Abundant macro and microremains in the form of tissues, phytoliths, crystals, cell structures, and others, were identified as Prosopis, Atriplex, Schoenoplectus, Distichlis, and Phragmites. We conclude that camelids were foraging for Prosopis, although the rather low number of entire seeds preserved in the coprolites leads us to think that these herbivores might not have been the main vectors for the spread and germination of algarrobos. More samples and interdisciplinary studies are needed to comprehend the complex socioecological web in the shaping of these forests and the management of the Atacama Desert landscapes.

The Younger Dryas (YD) impact hypothesis posits that fragments of a large, disintegrating asteroid/comet struck North America, South America, Europe, and western Asia ~12,800 years ago. Multiple airbursts/impacts produced the YD boundary layer (YDB), depositing peak concentrations of platinum, high-temperature spherules, meltglass, and nanodiamonds, forming an isochronous datum at >50 sites across ~50 million km² of Earth’s surface. This proposed event triggered extensive biomass burning, brief impact winter, YD climate change, and contributed to extinctions of late Pleistocene megafauna. In the most extensive investigation south of the equator, we report on a ~12,800-year-old sequence at Pilauco, Chile (~40°S), that exhibits peak YD boundary concentrations of platinum, gold, high-temperature iron- and chromium-rich spherules, and native iron particles rarely found in nature. A major peak in charcoal abundance marks an intense biomass-burning episode, synchronous with dramatic changes in vegetation, including a high-disturbance regime, seasonality in precipitation, and warmer conditions. This is anti-phased with northern-hemispheric cooling at the YD onset, whose rapidity suggests atmospheric linkage. The sudden disappearance of megafaunal remains and dung fungi in the YDB layer at Pilauco correlates with megafaunal extinctions across the Americas. The Pilauco record appears consistent with YDB impact evidence found at sites on four continents.

South America is well known for its abundance of Quaternary fossiliferous deposits, but well-preserved fossil remains from well-dated sites are scarce in the Atacama Desert and adjacent arid Andes. Here we report on a partially complete skeleton (46%) of a single young (ca. 3–4 years old) extinct horse discovered in the Salar de Surire, a salt flat located on the Andean altiplano of northern Chile (4,250 m asl). Comparative and osteometric morphological analyses identify the specimen as a South American endemic horse Hippidion saldiasi Roth, 1899. A direct AMS radiocarbon date on bone collagen yielded a calibrated age of 13,170 cal yr BP (2σ range: 13,300–13,060 cal yr BP) indicating that it lived near the end of the last glaciation. The body mass of the individual was calculated at approximately 326.4 kg, close to the upper limit of the larger sizes reported for the genus. Stable isotope evidence shows that the Salar de Surire horse relied on an almost 100% C3 diet that is mostly consistent with Hippidion specimens from other environments that also consumed either mixed C3/C4 or fully C3 diets. This finding is now the southernmost high-elevation record for this species and provides further evidence for the broad geographic and ecological distribution of this genus throughout southern South America.

The Geometric Lorenz Attractor has been a source of inspiration for many mathematical studies. Most of these studies deal with the two or one dimensional representation of its first return map. A one dimensional scenario (the increasing-increasing one's) can be modeled by the standard two parameter family of contracting Lorenz maps. The dynamics of any member of the standard family can be modeled by a subshift in the Lexicographical model of two symbols. These subshifts can be considered as the maximal invariant set for the shift map in some interval, in the Lexicographical model. For all of these subshifts, the lower extreme of the interval is a minimal sequence and the upper extreme is a maximal sequence. The Lexicographical world (LW) is precisely the set of sequences (lower extreme, upper extreme) of all of these subshifts. In this scenario the topological entropy is a map from LW onto the interval \begin{document}$[0, \log{2}]$\end{document} . The boundary of chaos (that is the boundary of the set of \begin{document}$ (a, b) ∈ LW$\end{document} such that \begin{document}$h_{top}(a, b)>0$\end{document} ) is given by a map \begin{document}$ b = χ(a)$\end{document} , which is defined by a recurrence formula. In the present paper we obtain an explicit formula for the value \begin{document}$χ(a)$\end{document} for \begin{document}$a$\end{document} in a dense set contained in the set of minimal sequences. Moreover, we apply this computation to determine regions of positive topological entropy for the standard quadratic family of contracting increasing-increasing Lorenz maps.

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.

The Laguna de Tagua Tagua has yielded two important late Pleistocene archaeological sites, Taguatagua 1 and Taguatagua 2, in which a clear early human exploitation of megafauna has been recorded. Particularly in Taguatagua 1 (TT-1), here re-dated around 12,600 cal yr BP, an abundant small faunal assemblage was also recovered, which had not been previously studied in detail. Here we report the first comprehensive taxonomic and taphonomic analysis of this site. We identified 28 different taxa, including mollusks, fish, anurans, reptiles, birds, marsupials, rodents, carnivores, gomphotheres, horses and cervids, making this the richest late Pleistocene site in Chile so far. Among these, sixteen taxa are new for the Chilean late Pleistocene. Birds are the richest group, with ten taxa, followed by rodents with eight taxa. Most of the species currently inhabit the area, but we identified some locally extirpated taxa, together with extinct taxa (exclusively megamammals). Taphonomic analysis suggests a very complex depositional scenario, mostly related to lake-level oscillations which covered and exposed a mainly natural deposited small faunal assemblage. So far, we detected human-made modifications exclusively in horse and cervid bones. Current habitat requirements of the extant fauna, as well as dietary reconstruction of extinct fauna, suggest a highly variable climate and vegetation during the formation of TT-1 since taxa with preferences from semiarid to humid/wooded environments were identified. These results can be related to the changes from cold/wet to dry/warm conditions documented during the Pleistocene - Holocene transition.

International audience; Along the Atacama Desert coast, fish has always been a staple food and by the Formative period (500 cal B.C.-700 cal A.D.) it had become a product in high demand by the inhabitants of the inland valleys, oases and ravines of the desert. In this paper we explore the technologies used in coastal fishing activities, the diverse species caught, and fish processing and preserving techniques. We further examine the circulation routes of the product through the desert and associated strategies, the agents involved in transporting it and consumption levels in inland villages. Our study employs a multivariate analysis that includes evidence from zooarchaeology, stable isotope analysis of deceased individuals, and the composition of human coprolites, all of which were recovered from domestic waste, funerary contexts, and rest stops associated with the circulation routes running between the coast and the inland desert regions. Our results suggest that in this ancient social context, food was not only used to quell hunger, but through its associated economic cycles of production, circulation and consumption, was part of a complex and extended web of social relations. Within that network, food functioned as material culture, and as such enabled social distinctions to emerge within local groups and cultural negotiations to be conducted among different localities. Fish circulation and consumption played an active role in the reproduction of a social structure characterized by close and firm ties between marine hunter-fisher-gatherers and agropastoral communities, despite their long distance from each other.

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.

Se presentan los resultados de un proyecto FONDART orientado a describir sistemáticamente pinturas y grabados rupestres de tres cuevas emplazadas en el litoral de la Patagonia septentrional chilena, recientemente descubiertas. Se registraron 47 pinturas rojas y nueve grabados lineales, con variaciones en la distribución de los motivos, tanto al interior de cada cueva como entre ellas. Aunque no se alcanzó la base de los depósitos, los trabajos realizados proveen el marco inicial para futuros estudios.

International audience; The archaeology from the Atacama Desert littoral had centered their studies into a reduced animal spectrum, over representing those more traditional, known, and popular, as fishes, camelids and otarides, in detriment of others, with a less bounded but equally significant register. We present a reflection about humans and sea turtles relationships, practically absents from the besti ary of the northern Chile littoral populations, focusing in their interespecies relations, highlighting the diversity of strategies, instances, and mechanism through which this those relations where constructed and acted.; La arqueología del litoral del desierto de Atacama ha concentrado sus estudios en un espectro reducido de animales, sobrerrepresentando los más tradicionales, conocidos y populares, como peces, camélidos y otáridos, en desmedro de otros con un registro más acotado pero igualmente significativo. Presentamos una reflexión acerca de las relaciones entre seres humanos y tortugas marinas, destacando la diversidad de estrategias, instancias y mecanismos a través de los cuales estas relaciones se construían y actuaban.

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.

International audience

Este trabajo evalúa, desde una perspectiva tecnológica y conductual, tendencias a largo plazo de cambio y continuidad en las estrategias de aprovechamiento de recursos faunísticos y líticos en contextos de cazadores-recolectores cordilleranos de Chile central. Para esto, tomamos los datos procedentes de un contexto ubicado en la cuenca superior del río Maipo: Caletón Los Queltehues, y escogimos, de su secuencia ocupacional, los componentes Arcaico IV y Alfarero temprano (5000 a 1000 AP). Los resultados de los análisis no arrojaron mayores variaciones entre ambos períodos en términos de taxones explotados, frecuencia de partes esqueletarias, modificaciones culturales y fragmentación de los restos óseos. De manera similar, las materias primas, las categorías morfofuncionales y los tipos de desechos líticos se observaron relativamente constantes. Sólo se registraron cambios en la tasa de la depositación, la frecuencia de modificaciones naturales y la diversidad de actividades de uso/descarte lítico, las que son interpretadas como una tendencia hacia una variación en la recurrencia e intensidad de la ocupación, pero no en cuanto a su funcionalidad.This article evaluates long-term trends in change and continuity of lithic and faunal use strategies in hunter-gatherer contexts in the central Chilean cordillera from technological and behavioral perspectives. The main objective of the analysis is to articulate both lines of evidence from a behavioral and technological perspective in order to infer unknown elements of the function and organization of activities in this kind of archaeological context. As an initial example, the Archaic IV and Early Ceramic (5000-1000 BP) components from a classic site located in the upper valley of the Maipo river, Caletón Los Queltehues, were analyzed in detail. The results do not show significant variation between the periods in exploited taxa, skeletal part frequencies, cultural modifications, or fragmentation of bone remains. Likewise, lithic raw materials employed, morpho-functional categories, and types of debris remained relatively constant. In terms of changes, there were differences in deposition rate, frequency of natural modification, and diversity of use/discard activities of lithic remains, interpreted as different intensities and re-occupation of the site rather than changes in its functionality.

In this paper we characterize the kneading sequences associated to Lorenz maps of the interval.

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.

Los sitios arqueológicos finipleistocénicos de Fuego-Patagonia austral son bastante escasos. Se cuenta con apenas cinco de ellos para comprender un período que se extiende por cerca de 1000 años. Estos yacimientos coinciden con una etapa de cambios ambientales muy marcados y asisten a la extinción de la megafauna en la región, al igual que en el resto del continente americano. Todos ellos se ubican en cuevas y aleros rocosos. Los intentos por hallar nuevos emplazamientos en otros contextos del área no han dado los frutos esperados aún. Sin embargo, se analizan otras posibilidades de búsqueda a la luz de los resultados de los trabajos recientes de los paleobiólogos comprometidos en obtener registros cada vez más acuciosos del cambio climático y sus causas.

Newly described outerops, excavations and sediment cores from the region of Última Esperanza, Magallanes, contain tephra derived from the large late-glacial explosive Rl eruption of the Reclús 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 Rl 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 wave-cut terraces, and also caves, such as the Cueva de Milodón, 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 Península Antonio Varas west of Seno Ultima Esperanza, to-150 m a.s.l. aroundLago Sofía, anddownto-125 m a.s.l. along their easternmost margin. The presence of thick deposits of Rl tephra in some of the caves around Lago Sofía 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 oceupied these caves. The depositional environment of Rl 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 BF) 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 Península 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 Rl 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 Obstrucción. The final stage of lake drainage, from the lower terrace level (20-30 m a.s.l.) oceurred at 10.3 cal kyrs BP.En este trabajo reportamos hallazgos de tefras derivadas de la gran explosión volcánica tardiglacial Rl del volcán Reclús situado en la Zona Volcánica Austral Andina, a partir de nuevos afloramientos, excavaciones y testigos sedimentarios de lagos y pantanos, obtenidos en la región de Ultima Esperanza, Magallanes. Nuevas fechas asociadas a estos depósitos permiten refrnar su edad a 14,9 ka cal AP (12.670±240 14C años AP) y su volumen a >5 km³. Además, la ubicación geográfica y estratigráfica de Rl permite acotar la evolución del lago proglacial represado por hielo que se desarrolló al este de la cordillera al intervalo temporal entre el término del Ultimo Máximo Glacial y el Holoceno. Este lago proglacial generó terrazas y cuevas, producto de la acción del oleaje, como la Cueva de Mlodón, a lo largo de la terraza más alta y conspicua. La altitud actual de estas terrazas depende de la cantidad total de rebote isostático posglacial, el cual se desconoce. Debido a las variaciones en el rebote isostático posglacial, las terrazas lacustres más altas y prominentes disminuyen en altitud de oeste a este, desde -170 m s.n.m. en la Península Antonio Varas, al oeste del Seno Ultima Esperanza, a 150 m s.n.m. alrededor del lago Sofía y descienden hasta -125 m s.n.m. a lo largo de su margen más oriental. La presencia de grandes depósitos de la tefra Rl en algunas de las cuevas alrededor del lago Sofía indican que el lago proglacial ya había descendido, con respecto a su nivel más alto, antes de la erupción de Rl y de hecho incluso antes de 16,1 ka cal AP (13.560±180 14C años AP) que es cuando los mamíferos terrestres ocuparon por primera vez estas cuevas. El ambiente deposicional de Rl, en el registro sedimentario del pantano Dumestre, sugiere incluso que el nivel del lago era inferior a 80 m s.n.m. durante el momento de esta erupción. Probablemente el lago proglacial original habría drenado a este nivel a través de sectores de baja altitud ubicados entre fiordo Obstrucción y seno Skyring, siguiendo hacia el seno Otway para desembocar en el Océano Pacífico, una vez que el canal Jerónimo ya estaba libre de hielo antes de la erupción de Rl. Otro grupo de testigos, del sitio Eberhard, indican que el lago persistió a >70 m s.n.m. hasta 12,8 ka cal AP (10.695±14C años AP). Sin embargo, a 14,2 ka cal AP (12.125±14C años AP), la pelvis de Mylodon de un sitio cercano, ubicado a 7 m s.n.m., sugiere que el lago podría haberse vaciado temporalmente durante este período. Este último dato, combinado con la ausencia de terrazas prominentes entre las más altas (170-125 m s.n.m.) y las más bajas (a solo 30 m s.n.m. en la Península Antonio Varas y 20 m s.n.m. a lo largo de la costa norte y sur de Puerto Natales), sugiere cambios abruptos en el nivel del lago proglacial después de la erupción de Rl. Probablemente el mecanismo que ocasionó estos cambios en Ultima Esperanza fue la ruptura catastrófica y el subsecuente resellamiento del dique de hielo que bloqueaba el Paso Kirke, el único paso al Océano Pacífico bajo el nivel del mar al norte del fiordo Obstrucción. El drenaje final del lago, desde la terraza inferior (20-30 m s.n.m.), ocurrió a los 10,3 ka cal AP.

El presente trabajo discute el estatus taxonómico de la especie Antifer niemeyeri Casamiquela, 1984, definida a partir de astas completas procedentes de la laguna Taguatagua y la quebrada de Quereo (Pleistoceno tardío-Holoceno temprano), en Chile central (30-35°S). Se concluye, a partir de un estudio morfológico y morfométrico detallado, que Antifer niemeyeri debe ser considerado sinónimo de Antifer ultra Ameghino, 1889 dados los caracteres anatómicos compartidos con esta especie. Los resultados amplían la distribución geográfica del taxón, que previamente se registraba en Argentina, Uruguay y sur de Brasil, y confirman su biocrón para el Pleistoceno tardío-Holoceno temprano (edad Lu-janense), aun cuando las fechas radiocarbónicas de Chile central (ca. 9.900 años 14C AP) corresponden a las más tardías para la especie. A la luz de la evidencia paleoclimática disponible, se vincula A ultra durante el Pleistoceno de Chile central a ambientes cálidos y abiertos. Considerando estos requerimientos, se discute su posible vía de ingreso al actual territorio chileno a través de corredores ubicados hacia el sur del macizo andino, y su coexistencia con Hippocamelus bisulcus Molina, 1782. De acuerdo a la información estratigráfica y paleoambiental, se postula que ambas especies habrían sido alopátridas, por lo menos en el área de estudio.This paper discusses the taxonomic status of Antifer niemeyeri Casamiquela, 1984, defined from complete antlers from Taguatagua lake and Quereo canyon, both located in central Chile (30-35°S). From a detailed morphological and moiphometrical study, it is concluded that Antifer niemeyeri should be considered synonymous with Antifer ultra Ameghino, 1889, due to the anatomical characters shared between both forms. These results expand the geographical distribution of this taxa previously recorded in Argentina, Uruguay and southern Brazil, confirming their late Pleistocene-early Holocene biochron, in spite the fact that radiocarbon dates obtained in central Chile (ca. 9.900 14C yr BP) imply the youngest age for the species. According to the available paleoclimate evidence, A. ultra is linked to warm climate and an open landscape during the late Pleistocene of central Chile. Its possible routes of entry to central Chile through corridors located at the south of the Andean range and its coexistence with Hippocamelus bisulcus Molina, 1782, are also discussed. According to the stratigraphic and paleoenvironmental data we suggest that both species have been allopatric, at least in the study area.

En la presente nota se informa sobre la presencia de arte rupestre en el litoral de la Patagonia septentrional de Chile, absolutamente desconocido antes. Los registros fueron hallados en cuevas del morro Vilcún (42º49`S-72º50`O), sector Santa bárbara, y corresponden tanto a pinturas como a grabados. Estas cuevas están ubicadas aproximadamente a 15 kilómetros al norte de la ciudad de Chaitén. No se encontró material arqueológico en superficie.The presence of rock art in the northern Patagonian coast is reported for the frst time. The findings correspond to caves on the Vilcún hill (42º49`S-72º50`O), Santa bárbara, close to the modern city of Chaitén and are both paintings and engravings. No surface archaeological materials were found.

Southern Patagonia is rich in late Pleistocene mammals, especially herbivores such as Camelids, Equids and Xenarthrans. Carnivores, on the other hand, are not commonly found in the paleontological record. One genus, Smilodon, is of particular interest because its presence in the region has not been demonstrated. In this paper, we present new fossil dental evidence that supports the presence of Smilodon populator (Lund) in the region. This evidence corresponds to the most southern record of the genus in the world, and the final step in the colonization of South America after the Great American Biotic Interchange. An AMS radiocarbon date on teeth indicates that the remains from Southern Chilean Patagonia are the most recent record for the genus in South America.Surpatagonia es particularmente rica en mamíferos finiplesitocenos, particularmente camélidos, équidos y xenartros. Los carnívoros, por su parte, se encuentran representados en menor número en el registro paleontológico. Dentro de estos, el género Smilodon, es de particular interés debido a que su presencia en la región no ha sido convincentemente demostrada. En este trabajo presentamos evidencia dental que permite confirmar la presencia de Smilodon populator (Lund) en la región. Esta evidencia corresponde al registro más sureño de este taxón y al paso final en la colonización de América del Sur después del Gran Intercambio Biótico Americano. Un fechado radiocarbónico directo AMS indica que los restos de Patagonia del Sur corresponden a los registros más tardíos para este género en el subcontinente.

A partir de un análisis zooarqueológico se discute la posibilidad de detectar diferencias en las opciones dietarias de dos segmentos de la población, casados y solteros, del asentamiento minero histórico de Capote durante la primera mitad del s. XX. En base a la frecuencia de partes esqueletarias de taxones principalmente domésticos, así como a la abundancia y diversidad de éstos, se demuestra que el grupo casado se alimenta mejor que el grupo soltero, ya que el primero depende de las decisiones domésticas tomadas al interior de su núcleo familiar, mientras que el segundo se acoge a un régimen alimenticio minero tendiente a maximizar los recursos.Based on zooarchaeological analyses, we discuss the possibility of detecting differences in the dietary choices of two population segments, singles and married, at the mining settlement of Capote during the first half of XX Century. Keeping in mind the frequency of skeletal parts of domestic taxa, and their diversity, it is demonstrated that the married are better fed than singles. The former depend on the decisions of their women, while singles were subject to a that is primarily focused to a more restrictive diet that is primarily focused on resource maximization.

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.Palabras clave: género Vicugna, osteometría, Pleistoceno, Patagonia AbstractThis contribution presents the results of single and multi-variable osteometric analyses performed on a sample of short bones and phalanxes assigned to Vicugna sp. from Lago Sofía Cave 4 site (13500 – 11000 BP), Región de Magallanes, Chile. The elements analyzed show a similar size to the reference collections for Vicugna vicugna, and do not exceed the metrics for the pampean pleistocenic specimens of Vicugna gracilis. This confirms the morphological and ancient DNA data that indicated the presence of vicuña in southern Chilean Patagonia. The taxonomic, biogeographic and palaeoecologic discussion of these results, suggests that the presence of this species outside its current distribution range was due to shared environmental conditions between the Puna and Patagonia during the Pleistocene-Holocene transition. The extinction of this form is, most likely, due to the impact of climatic change during the begining of the Holocene over its pasturing diet and its territorial and non migratory habits. It is added to this, a hunting pressure by human and non-human predators.Keywords: Vicugna genus, osteometry, Pleistocene, Patagonia

In the present paper we characterize the boundary of topological chaos and the levels of the entropy for the Milnor–Thurston shift map.

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.

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.The results of taxonomic and taphonomic analyses from the lowermost layers of the Cueva Las Guanacas archaeological site (XI Región, Chilean Central Patagonia) are presented. Eight major taxa have been identified, among them four extinct (Mylodon darwini Owen, Macrauchenia patachonica Owen, Hippidion saídiasi Roth and Camelidae indet.) and other four currently living on the valley or nearby áreas (Hippocamelus bisulcus Molina, Pudú pudú Molina, Lama guanicoe Müller y Dusicyon culpaeus Molina). The taphonomic analysis confirms the non-cultural nature of the early levéis and instead backs up the idea of non human predators occupying the cave. Resorting to many different lines of evidence (ethology of Pleistocene predators, observed taxonomic and skeletal profiles, gastric acid corrosión and other damages), it is claimed that the agent responsible for the Pleistocene/Holocene bone assemblage at cueva Las Guanacas were carnivores (including a mid-sized feline, possibly Panthera onca Linnaeus). These predators would have had deveoped several strategies to obtain the carcasses, including active hunt and scavenging around 13.200 BP.

Se presenta información referida a los sitios arqueológicos con arte rupestre conocidos hasta el momento en la cuenca del río Manso (Norpatagonia), en territorio argentino, y a dos sitios recientemente relevados ubicados en el valle de dicho río en Chile. Las relaciones estilísticas entre los sitios de ambos sectores de la Cordillera de los Andes permiten incluirlos dentro de una misma unidad cultural y temporal, relacionada con el estilo de Grecas o TAGC y también con la modalidad del Ámbito Boscoso Lacustre del Nordeste de Patagonia propia de los cazadores recolectores del Holoceno tardío en Patagonia.This paper presents information related to archaeological sites with rock art known so far in the basin of Manso river (northern Patagonia), in Argentine territory, and two sites recently discovered in the valley of the same river in Chile. The stylistic relations between all the sites located en both sides of the Cordillera de los Andes permits their inclusión in the same cultural and temporal unit related to the Grecas style o TAGC, and specially the Ámbito Boscoso Lacustre modality of the hunther gatherers's of the late Holocene in Patagonia.

Se describen restos del género Hippidion procedentes de la zona del desierto de Atacama (Calama, Segunda Región de Chile). El conjunto analizado corresponde a un esqueleto bastante completo proveniente del yacimiento Betecsa 1, así como escasas unidades del yacimiento Kamac Mayu. En ambos sitios se identifica H. saldiasi. A partir de dos dataciones radiométricas por AMS del ejemplar estudiado, los restos se sitúan estratigráficamente en el Pleistoceno Superior (21.070 ± 100 AP y 21.380 ± 100 14C AP). Se infieren datos ambientales y de dieta a partir de análisis de isótopos estables en los restos de Hippidion saldiasi del sitio Betecsa 1 cuyo valor de δ13C en hueso fue de -15,45 y el valor en esmalte de dientes fue de -16,68, sugiriendo una alimentación con pastos C3. El cráneo recuperado es el primero conocido de esta especieThis paper describes the Hippidion bones recovered from the Atacama Desert (Calama, Second Region of Chile). The analyzed assemblage corresponds to a nearly complete skeleton from Betecsa 1 site and more poorly preserved remains from Kamac Mayu site. In both H. saldiasi is identified. Two 14C radiometric determinations indicate late Pleistocene age for these remains (21,070 ± 100 BP and 21,380 ± 100 BP). Environmental and diet inferences from stable isotope analysis are also presented. The δ13C value from Betecsa 1 horses (-15.45 from bone sample and -16.68 from enamel sample) suggest a dietary adaptation exclusively C3 feeders. This is the first skull and associated skeleton recovered of this species

Se presentan los resultados del análisis de huellas de corte en restos óseos de pinnipedos provenientes de dos yacimientos loberos históricos, localizados en cabo Shirreff, isla Livingston, Antartica Chilena. Se describe la ubicación, disposición y características morfológicas de las huellas, con el objeto de establecer los modos de procesamiento llevados a cabo en los yacimientos estudiados. Los resultados indican que los cortes fueron hechos con instrumentos metálicos, en su mayoría orientados a la extracción de la piel, con un procedimiento muy estandarizadoThe paper presents the results of an analysis of cut marks on pinniped bones recovered at two historic age sites located in Cape Shirreff, Livingston Islands, Chilean Antarctica. The location, disposition and morphological characteristics of each mark are described in order to identify butchering patterns employed at the studied sites. The study concludes that the marks were made with a metal tool and generally followed a very standardized procedure geared towards the skinning of animals

In this paper we describe some topological and geometric properties of the set of sequences LW = { ( a , b ) ∈ Σ 0 × Σ 1 ; a ⩽ σ n ( a ) ⩽ b , a ⩽ σ n ( b ) ⩽ b , ∀ n ∈ N } , which essentially represents all the allowed dynamics for piecewise continuous increasing maps with one discontinuity. In particular, we describe the first main bifurcations in LW which generate non-trivial dynamics, and we study (fractal) geometric properties of LW and of the phase spaces Σ a , b associated to it.

La interacción entre fauna extinguida y el hombre durante la transición Pleistoceno-Holoceno en Chile centro-sur (latitudes 31 °S y 42°S), ha carecido de trabajos sistemáticos o programas de investigación, lo que se ve reflejado en la presencia de tan sólo cuatro sitos aislados de características muy disimiles entre si. El presente trabajo examina la literatura producida en tomo a estos sitios, aportando información de estudios recientes, reinterpretando en algunos casos la evidencia «clásica» a la luz de nuevas concepciones teóricas. Se observa que de todo el variado elenco faunistico que habitaba la región durante este momento, sólo un reducido número de especies fue efectivamente utilizada por los primeros pobladores de la región, al parecer de manera no intensiva, lo que no explica el gran número de especies que desaparecieron comenzado el Holoceno. Se plantea la necesidad de abordar la problemática de los primeros habitantes de la región de forma mucho más flexible, revalorando el papel de la recolección y la caza de fauna moderna, situando a la fauna extinguida sólo como una opción a considerar dentro de estrategias de subsistencia mayores, las que requieren ser investigadas.

Se presentan los resultados del análisis zooarqueológico realizado a los restos de mastodontes exhumados de la Quebrada Quereo a finales del siglo antepasado, con el objeto de evaluar una posible acción cultural en ellos. Se discuten los resultados en términos de la relación hombre-mastodonte en el lugar y se presenta un modelo hipo- tético de interacción entre este proboscídeo extinto y los más tempranos habitantes del sector.

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.

In this article we provide, by using kneadings sequences, the combinatorial bifurcation diagramme associated to a typical two parameter of Lorenz maps on the real line. We apply these results to two parameter families of geometric Lorenz-like flows.

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 ...

In this article we consider two kinds of complex singular cycles arising for vector fields defined on three-dimensional manifolds. We prove that, under some generic conditions, any one parameter family of vector fields passing through these cycles has the following property: Hyperbolicity is a prevalent phenomena.

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.

In the present paper we deal with the Milnor-Thurston world and we present elementary proofs of some results by combining dynamics, combinatory, linear algebra and entropy.

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.