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Casas de Fernando Alonso, Spain

Ros-Montoya S.,Museo de Prehistoria y Paleontologia Municipal de Orce | Madurell-Malapeira J.,Autonomous University of Barcelona | Martinez-Navarro B.,Rovira i Virgili University | Espigares M.-P.,Museo de Prehistoria y Paleontologia Municipal de Orce | Palmqvist P.,Campus Universitario Of Teatinos
Quaternary International | Year: 2012

The late Early Pleistocene (Late Villafranchian) paleontological sites of Incarcal-I (Crespià, Catalonia, Spain) and Venta Micena (Orce, Andalusia, Spain), which are approximately 800 km apart, preserve a rich fossil record of proboscideans, corresponding to the species Mammuthus meridionalis. The remains from Incarcal-I have been described as an evolved form of the species. However, their comparison with the mandible of the same species from Venta Micena (with an approximate age of 1.4-1.6 Ma) and other specimens from different sites in Europe and Asia shows that the fossils from Incarcal-I and Venta Micena are very similar in morphology and metric data. Research suggests that the Catalonian specimens correspond to a form of the former species, which according to their morphology probably have a chronology closer to that of the Venta Micena specimens. © 2012 Elsevier Ltd and INQUA.

Palmqvist P.,Campus Universitario Of Teatinos | Gonzalez-Donoso J.M.,Campus Universitario Of Teatinos | De Renzi M.,University of Valencia
Quaternary Science Reviews | Year: 2014

Lozano-Fernández etal. (2013a) have recently published a method intended for numerical dating of Early Pleistocene sites, which is based on the assumption of uniform, constant rate increase through time of mean lower molar tooth length of water voles (Mimomys savini) in a number of levels sampled in the stratigraphic sequence of Atapuerca TD site. They suggest that the regression equation obtained in this local section for site chronology on tooth size could be useful for estimating the numerical age of other localities from southwestern Europe. However, in our opinion this biostratigraphic approach has severe conceptual and methodological problems, which discourage its use as a chronometric tool. These problems include that: (1) the logic behind their approach represents a 'fallacy of hasty generalization', because the results obtained for a local section are generalized to all possible stratigraphic sequences; (2) the study is based on tooth measurements from a limited set of samples taken in a single locality, which are represented by small numbers of specimens, cover a short time span and have a high level of age uncertainty; (3) the samples analyzed show small, statistically non-significant differences between their mean tooth length values; (4) the approach assumes a linear-straight, orthoevolutionary model of change at constant, monotonic rate for the apparent trend to increasing tooth size in the M.savini lineage; (5) these changes are better described in the Atapuerca TD section by a random walk, or even by a series of independent events, than by a model of rectilinear change; and (6) the application of this methodology to other localities such as the Orce sites, which preserve the oldest evidence of human presence in Europe, would mean that an equation adjusted within a restricted chronological range (1.01-0.8Ma) is used for extrapolating the ages of sites that are clearly older (~1.4Ma). © 2014 Elsevier Ltd.

Jimenez-Arenas J.M.,University of Granada | Palmqvist P.,Campus Universitario Of Teatinos | Perez-Claros J.A.,Campus Universitario Of Teatinos
Quaternary International | Year: 2011

There is probably no paleoanthropological issue with deeper disagreements than the taxonomic status of the Early-Middle Pleistocene members of the genus Homo One reason could be the difficulty of estimating the relationship between morphological and taxonomic diversity. In an attempt to contribute new evidence to this debate, bootstrapping techniques are used for analyzing the cranial variability of Homo. The results indicate that: (i) the size of the neurocranium relative to the viscerocranium discriminates better among extant hominoid species than skull size; (ii) no cluster of fossil specimens of Homo exceeds the morphological variability of Gorilla gorilla, with the only exception of the one that comprises all members of Homo except modern humans; and (iii) some clusters are taxonomically more consistent than others, as long as they show a range of morphological variability similar to that found in both Pan troglodytes and Homo sapiens. According to these results, three taxa are tentatively suggested for Homo: (i) anatomically modern humans; (ii) an "erectine" morphotype plus Neanderthals; and (iii) a "habiline" cluster. Finally, the results indicate a greater taxonomic affinity for the human population involved in the first dispersal "Out of Africa" with the "habiline" group, which agrees with the early age reported for Dmanisi (1.77 Ma), a Georgian site placed at the gates of Europe. © 2011 Elsevier Ltd and INQUA.

Garcia-Aguilar J.M.,Campus Universitario Of Teatinos | Palmqvist P.,Campus Universitario Of Teatinos
Quaternary International | Year: 2011

The Early Pleistocene deposits of Guadix-Baza basin represent a depositional unit with distinctive features in the tectosedimentary history of this intramontane basin, which sedimentary infillings range in age between the uppermost Miocene and 45 ka. This Pleistocene unit has an average thickness of 10 m and is composed of carbonate lacustrine facies arranged in an upward-shallowing sequence. The paleontological richness of this unit is evidenced by its special sedimentological and paleoecological features. Diverse numerical analytic data related with the evolution of the sedimentary sequences and the establishment of the sedimentary and paleoecological scenario are presented. © 2011 Elsevier Ltd and INQUA.

Garcia-Aguilar J.M.,Campus Universitario Of Teatinos | Guerra-Merchan A.,Campus Universitario Of Teatinos | Serrano F.,Campus Universitario Of Teatinos | Palmqvist P.,Campus Universitario Of Teatinos | And 2 more authors.
Quaternary Science Reviews | Year: 2014

The continental sedimentary record of the Baza Basin (Guadix-Baza Depression, Betic Cordillera, SE Spain) shows six sedimentary units of lacustrine origin deposited from the latest Miocene to the Middle Pleistocene. Depending on the interval considered, the lacustrine deposits are mainly composed of marls, carbonates or gypsiferous evaporites, showing lithological, mineralogical and geochemical features (i.e., magnesium, strontium and sulfur contents, celestine deposits and travertine growths) that are evidence of intense, tectonically-induced hydrothermal activity. According to the high concentrations of strontium and sulfur as well as the abundance of travertines and magnesium clays, the supply of hot waters was greater during the Zanclean, the Gelasian and the Calabrian, as a result of tectonic activity. Hydrothermal activity has continued until the present time and is responsible of the hot springs that are nowadays active in the Guadix-Baza Depression. The paleoenvironmental consequences of these sublacustrine hot springs were that during some intervals the lakes maintained a relatively permanent water table, not subject to periodic desiccations in the dry season, and warmer temperatures throughout the year. This resulted in a high level of organic productivity, especially for the Calabrian, which allowed the development of a rich and well diversified mammalian community, similar to those of modern African savannas with tree patches. In this mild environment, the permanent water sheet favored the presence of drought intolerant megaherbivores such as the giant extinct hippo Hippopotamus antiquus. The high standing crop biomass of ungulates resulted in the availability of abundant carcasses for scavengers such as hyenas and hominins, which explains the very high densities of skeletal remains preserved in the sediments distributed along the lake surroundings. © 2013 Elsevier Ltd.

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