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Rodents are a very useful tool in reconstructing the environment of the past, especially owing to their rapid response to climate change, their small home range, and their restricted habitat requirements. They are a highly diverse group of mammals, which have high reproduction rates and as a result can evolve rapidly. The abundance of their microfossil remains in archaeological and paleontological sites permits robust statistical analyses to reconstruct the past climate and environment. Recently, a number of studies have affirmed the need to deepen the climatic characterization of the European Quaternary, the Middle Pleistocene being an important stage for ascertaining how our hominin ancestors lived. The aim of this study is to characterize the climatic conditions in which hominins lived in southwestern Mediterranean Europe during the Middle Pleistocene. To reconstruct these climatic conditions, we apply the bioclimatic model to rodent assemblages from Middle Pleistocene sites with human remains (Caune de l'Arago, Sima de los Huesos, Aroeira cave, Visogliano, Trinchera Galeria, and Mollet cave). Based on the percentage distribution of the species in different climate types and applying multiple linear regressions, we estimated the mean annual temperature, the mean temperature of the coldest month, and the mean temperature of the warmest month. We compared these estimates with data collected over the last 30 years from nearby meteorological stations to obtain the differences with current climate and observe the fluctuations. The climatic conditions obtained from the results of this study show that, while in Iberia mild climatic condition prevailed, in southern France and northeastern Italy harsher weather conditions were indicated., Competing Interests: Declaration of competing interest The author declares that there is no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The transition from the Middle Palaeolithic (Mousterian) to the Upper Palaeolithic (Aurignacian) has been one of the prominent themes in the archaeology of the European Palaeolithic for more than 20 years. One of the most controversial questions concerning this period is the extinction of the Neanderthals and their replacement by modern humans. In this context, Cueva del Conde, located in the northern part of the Iberian Peninsula, is an archaeo-palaeontological site that records the Mousterian to Aurignacian transition. It has been excavated since the beginning of the 20th century, first by the Conde de la Vega del Sella and systematically by a team from the University of Oviedo since 2001. Three main zones have been identified: the External Zone, dated to approximately 39,110 ± 520 BP (level N104); the Entrance Platform, dated between 38,250 ± 390 BP and 34,730 ± 500 BP; and Gallery A with a radiocarbon date of approximately 31,540 ± 400 BP (level N2a2). The small-vertebrate assemblages recovered from the water-screening of all sediment from the excavation campaigns represent at least 21 small mammal, amphibian and squamate taxa. The small-vertebrate associations in the three zones suggest a patchy landscape, dominated by humid meadows and woodland areas with the existence of water in the vicinity of the cave. The climate shows a more continental pattern during the Mousterian, though it was milder during the Aurignacian. The small vertebrates of the Cueva del Conde Mousterian and Aurignacian levels suggest a climate that differed from modern day temperatures, between -1.1 and -4.4 °C (mean annual temperature), placing these assemblages during Interstadials 9 to 7 (Is9 to 7)., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The Gran Dolina cave site is famous for having delivered some of the oldest hominin remains of Western Europe (Homo antecessor, ca. 960 ka). Moreover, the evidence of lithic industries throughout the long vertical section suggests occupation on the part of hominins from the latest early Pleistocene (levels TD3/4, TD5, and TD6) to the late middle Pleistocene (level TD10). The Gran Dolina Sondeo Sur (TDS) has furnished a great number of small-vertebrate remains; among them some 40,000 bones are attributed to amphibians and squamates. Although they do not differ specifically from the extant herpetofauna of the Iberian Peninsula, the overlap of their current distribution areas (= mutual climatic range method) in Spain can provide mean annual temperatures (MAT), the mean temperatures of the coldest (MTC) and warmest (MTW) months, and mean annual precipitation (MAP) estimations for each sub-level, and their change can be studied throughout the sequence. Results from the squamate and amphibian study indicate that during hominin occupation the MAT (10-13 degrees C) was always slightly warmer than at present in the vicinity of the Gran Dolina Cave, and the MAP (800-1000mm) was greater than today in the Burgos area. Climatic differences between "glacial" and "interglacial" phases are poorly marked. Summer temperatures (MTW) show stronger oscillations than winter temperatures (MTC), but seasonality remains almost unchanged throughout the sequence. These results are compared with those for large mammals, small mammals, and pollen analysis, giving a scenario for the palaeoclimatic conditions that occurred during the early to middle Pleistocene in Atapuerca, and hence a scenario for the hominins that once lived in the Sierra de Atapuerca.

Level TD6 of the Trinchera Dolina Section in the railway cutting of the Sierre de Atapuerca (Trinchera del Ferrocarril) has yielded a rich small mammal assemblage (26 species) in association with fossil human remains of Homo antecessor. The arvicolids of TD6 are identified as: Mimomys savini, Microtus seseae, Stenocranius gregaloides, Terricola arvalidens, Iberomys huescarensis, Allophaiomys chalinei, and Pliomys episcopalis. The rodent association also includes large rodents (i.e., Castor fiber, Marmota sp., and Hystrix refossa) and the small Allocricetus sp., Eliomys helleri, Micromys minutus, and Apodemus aff. flavicollis. The small vertebrate remains also include Insectivora (Beremendia fissidens, Sorex sp, Neomys sp., Crocidura sp., Galemys sp., Talpa sp., Erinaceus sp.), Chiroptera (Miniopterus schreibersii, Myotis sp., Rhinolophus sp.), and Lagomorpha (Oryctolagus sp., Lepus sp.), as well as lizards, birds and amphibians. The H. antecessor remains are derived from a 15 cm thick layer at the top of TD6 (TD6-T36-43), where A. chalinei, H. refossa and Marmota sp. do not occur. The paleomagnetic Matuyama/Brunhes boundary is found in the overlying level TD7 of the Gran Dolina Section. On the basis of the arvicolids, TD6 can be referred to the Biharian biochron. The Matuyama/Brunhes boundary is fixed in the late Biharian (Microtus-Mimomys rodent Superzone). The species M. savini (without M. pusillus), as well as the evolutionary stage of Microtus s.l., are characteristic of the Late Biharian. The evolutionary level of the species M. savini, T. arvalidens, S. gregaloides indicates that TD6 is older than West Runton (type Cromerian). In the Trinchera Dolina Section we are able to calibrate, for the first time, the evolutionary level of important biochronological markers with magnetostratigraphy. We propose that a radiation of Microtus s.l., along with the first appearance of primitive S. gregaloides, T. arvalidens and Iberomys, took place just before the Matuyama/Brunhes boundary. These species can be considered as characteristic elements of early Pleistocene faunas., (Copyright 1999 Academic Press.)

A small collection of rodents from Sima de los Huesos helps to clarify the stratigraphic position of this famous human locality. The presence of Allocricetus bursae and Pliomys lenki relictus and the size of A. bursae, Apodemus sylvaticus and Eliomys quercinus suggest a Middle Pleistocene age (Saalian) to the Clays where humans have been found.