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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.)

We have developed a protocol for reconstructing 3D models of the skulls of extinct species of small mammals. For the first time, the reconstruction uses fragments of fossils from a mixture of different specimens and from related extant species. We use free software and commercial computers to make the process reproducible and usable for the scientific community. We present a semi-quantitative protocol to face the problem of making 3D reconstructions of fossil species that are incomplete in the fossil record and/or represented by a mixture of different individuals, as usually occurs with small vertebrates. Therefore this approach is useful when no complete skull is available. The protocol combines the use of microCT scan technology with a subsequent computer treatment using different software tools for 3D reconstruction from microCT and 3D design and printing (e.g. Fiji, SPIERS, Meshlab, Meshmixer) in a defined order. This kind of free and relatively simple software, plus the detailed description, makes this protocol practicable for researchers who do not necessarily have great deal of experience in working with 3D. As an example, we have performed virtual reconstructions of the skulls of two species of insectivore small mammals (Eulipotyphla): Beremendia fissidens and Dolinasorex glyphodon. The resulting skulls, plus models of the extant shrews Blarina brevicauda, Neomys fodiens, Crocidura russula and Sorex coronatus, make it possible to compare characteristics that can only be observed by means of microCT 3D reconstructions, and given the characteristics of the material, using this protocol. Among the characters we can compare are the position of the mandibles, the spatial relations among all the teeth, the shape of the snout and, in general, all parameters related with the anatomy of the rostrum. Moreover, these reconstructions can be used in different types of context: for anatomical purposes, especially to see internal features or characteristics at whole-skull scale, for bioengineering, animation, or other techniques that need a digital model., Competing Interests: The authors have declared that no competing interests exist.

Introduction and Objectives: Although the Iberian Peninsula is a key area for understanding the Middle to Upper Paleolithic transition and the demise of the Neandertals, valuable evidence for these debates remains scarce and problematic in its interior regions. Sparse data supporting a late Neandertal persistence in the Iberian interior have been recently refuted and hence new evidence is needed to build new models on the timing and causes of Neandertal disappearance in inland Iberia and the whole peninsula. In this study we provide new evidence from Los Casares, a cave located in the highlands of the Spanish Meseta, where a Neandertal-associated Middle Paleolithic site was discovered and first excavated in the 1960's. Our main objective is twofold: (1) provide an updated geoarcheological, paleoenvironmental and chronological framework for this site, and (2) discuss obtained results in the context of the time and nature of the last Neandertal presence in Iberia., Methods: We conducted new fieldwork in an interior chamber of Los Casares cave named 'Seno A'. Our methods included micromorphology, sedimentology, radiocarbon dating, Uranium/Thorium dating, palinology, microfaunal analysis, anthracology, phytolith analysis, archeozoology and lithic technology. Here we present results on site formation processes, paleoenvironment and the chronological setting of the Neandertal occupation at Los Casares cave-Seno A., Results and Discussion: The sediment sequence reveals a mostly in situ archeological deposit containing evidence of both Neandertal activity and carnivore action in level c, dated to 44,899-42,175 calendar years ago. This occupation occurred during a warm and humid interval of Marine Isotopic Stage 3, probably correlating with Greenland Interstadial 11, representing one of the latest occurrences of Neandertals in the Iberian interior. However, overlying layer b records a deterioration of local environments, thus providing a plausible explanation for the abandonment of the site, and perhaps for the total disappearance of Neandertals of the highlands of inland Iberia during subsequent Greenland Stadials 11 or 10, or even Heinrich Stadial 4. Since layer b provided very few signs of human activity and no reliable chronometric results, and given the scarce chronostratigrapic evidence recorded so far for this period in interior Iberia, this can only be taken as a working hypothesis to be tested with future research. Meanwhile, 42,000 calendar years ago remains the most plausible date for the abandonment of interior Iberia by Neandertals, possibly due to climate deterioration. Currently, a later survival of this human species in Iberia is limited to the southern coasts.

Current knowledge of the evolution of the postcranial skeleton in the genus Homo is hampered by a geographically and chronologically scattered fossil record. Here we present a complete characterization of the postcranium of the middle Pleistocene paleodeme from the Sima de los Huesos (SH) and its paleobiological implications. The SH hominins show the following: (i) wide bodies, a plesiomorphic character in the genus Homo inherited from their early hominin ancestors; (ii) statures that can be found in modern human middle-latitude populations that first appeared 1.6-1.5 Mya; and (iii) large femoral heads in some individuals, a trait that first appeared during the middle Pleistocene in Africa and Europe. The intrapopulational size variation in SH shows that the level of dimorphism was similar to modern humans (MH), but the SH hominins were less encephalized than Neandertals. SH shares many postcranial anatomical features with Neandertals. Although most of these features appear to be either plesiomorphic retentions or are of uncertain phylogenetic polarity, a few represent Neandertal apomorphies. Nevertheless, the full suite of Neandertal-derived features is not yet present in the SH population. The postcranial evidence is consistent with the hypothesis based on the cranial morphology that the SH hominins are a sister group to the later Neandertals. Comparison of the SH postcranial skeleton to other hominins suggests that the evolution of the postcranium occurred in a mosaic mode, both at a general and at a detailed level.

The allometric-constraint hypothesis states that evolutionary divergence of morphological traits is restricted by integrated growth regulation. In this study, we test this hypothesis on a time-calibrated and well-documented palaeontological sequence of dental measurements on the Pleistocene arvicoline rodent species Mimomys savini from the Iberian Peninsula. Based on 507 specimens representing nine populations regularly spaced over 600 000 years, we compare static (within-population) and evolutionary (among-population) allometric slopes between the width and the length of the first lower molar. We find that the static allometric slope remains evolutionary stable and predicts the evolutionary allometry quite well. These results support the hypothesis that the macroevolutionary divergence of molar traits is constrained by static allometric relationships., (© 2014 The Author(s) Published by the Royal Society. All rights reserved.)

Seventeen Middle Pleistocene crania from the Sima de los Huesos site (Atapuerca, Spain) are analyzed, including seven new specimens. This sample makes it possible to thoroughly characterize a Middle Pleistocene hominin paleodeme and to address hypotheses about the origin and evolution of the Neandertals. Using a variety of techniques, the hominin-bearing layer could be reassigned to a period around 430,000 years ago. The sample shows a consistent morphological pattern with derived Neandertal features present in the face and anterior vault, many of which are related to the masticatory apparatus. This suggests that facial modification was the first step in the evolution of the Neandertal lineage, pointing to a mosaic pattern of evolution, with different anatomical and functional modules evolving at different rates., (Copyright © 2014, American Association for the Advancement of Science.)

Eating habits of Panthera pardus are well known. When there are caves in its territory, prey accumulates inside them. This helps to prevent its kill from being stolen by other predators like hyenas. Although the leopard is an accumulator of bones in caves, few studies have been conducted on existing lairs. There are, however, examples of fossil vertebrate sites whose main collecting agent is the leopard. During the Late Pleistocene, the leopard was a common carnivore in European faunal associations. Here we present a new locality of Quaternary mammals with a scarce human presence, the cave of Los Rincones (province of Zaragoza, Spain); we show the leopard to be the main accumulator of the bones in the cave, while there are no interactions between humans and leopards. For this purpose, a taphonomic analysis is performed on different bone-layers of the cave.

The vertebrate fossil record from the Balearic Islands (western Mediterranean) has improved considerably over the past decade, especially in Mallorca and Menorca. In Menorca, the Pliocene terrestrial fauna was updated by the discovery and description of the large-sized leporid Nuralagus, several reptiles and an amphibian. In Mallorca, paleontological exploration yielded 2 deposits with a Late Miocene/Early Pliocene chronology, Caló den Rafelino (CdR) and Na Burguesa-1 (NB-1). So far, 4 new mammalian taxa and 2 new reptiles have been identified for the CdR deposit, whereas the faunal assemblage from the recently discovered deposit (Apr 2012) of NB-1 is currently composed of, at least, 6 terrestrial mammals, 8 reptiles and an amphibian. Its faunal composition and some primitive characteristics of the obtained taxa suggest that the chronology of this deposit is slightly earlier than the CdR. The terrestrial vertebrates recorded in these 2 Mallorcan deposits are changing the view of the paleofaunal assemblage previously known for the Plio-Pleistocene of the island. Morphological characteristics displayed by some of the taxa suggest that these faunas would be at the beginning of an isolated evolution. In this paper we present a preliminary report on the fossils recovered from the NB-1 deposit, as well as some unpublished data from CdR, and we analyze the whole fauna from both Mallorcan deposits, focusing on taxonomical and paleobiogeographical aspects., (© 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.)

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 dispersal of hominins may have been favored by the opening of the landscape during the Early-Middle Pleistocene transition (EMP) in Western Europe. The structure of the small-vertebrate assemblages of the archaeo-paleontological karstic site of Gran Dolina in Atapuerca (Burgos, Spain) shows important environmental and climatic changes in the faunal succession, across the Matuyama-Brunhes boundary at 780 ka. These changes are interpreted to indicate impoverishment of the forests, along with an increase in dry meadows, and open lands in general that entailed a tendency towards the loss of diversity in small-vertebrate communities above the EMP. We evaluate variation in diversity of the faunal succession of Gran Dolina using Shannon's Second Theorem as an index of ecosystem structure. The long cultural-stratigraphic sequence of Gran Dolina during the EMP is somewhat similar in its completeness and continuity to that in the locality of Gesher Benot Ya'aqov in the Upper Jordan Valley. We also evaluate related data including faunal and floral (pollen) succession. Both localities present cold, dry and humid, warm fluctuations at the transition between the Early and the Middle Pleistocene. Comparisons between these sites present opportunities to understand large-scale climatic changes., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The earliest hominin occupation of Europe is one of the most debated topics in palaeoanthropology. However, the purportedly oldest of the Early Pleistocene sites in Eurasia lack precise age control and contain stone tools rather than human fossil remains. Here we report the discovery of a human mandible associated with an assemblage of Mode 1 lithic tools and faunal remains bearing traces of hominin processing, in stratigraphic level TE9 at the site of the Sima del Elefante, Atapuerca, Spain. Level TE9 has been dated to the Early Pleistocene (approximately 1.2-1.1 Myr), based on a combination of palaeomagnetism, cosmogenic nuclides and biostratigraphy. The Sima del Elefante site thus emerges as the oldest, most accurately dated record of human occupation in Europe, to our knowledge. The study of the human mandible suggests that the first settlement of Western Europe could be related to an early demographic expansion out of Africa. The new evidence, with previous findings in other Atapuerca sites (level TD6 from Gran Dolina), also suggests that a speciation event occurred in this extreme area of the Eurasian continent during the Early Pleistocene, initiating the hominin lineage represented by the TE9 and TD6 hominins.

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.

Human remains dating to more than 780,000 years ago are associated with a rich faunal and lithic assemblage in the Pleistocene cave site of Gran Dolina (TD), Sierra de Atapuerca, Burgos, Spain. The micromammal species represent the late Biharian (Mimomys savini zone), and the lithic objects represent pre-Acheulean technology (Mode 1) and comes from the TD6 level below the Matuyama-Brunhes boundary. The Gran Dolina hominid fossils cannot be comfortably accommodated in any of the defined Homo species. They could be considered a primitive form of Homo heidelbergensis, but a new species might be named in the future if the sample is enlarged. The new human fossil evidence demonstrates that Western Europe was settled at least since the late early Pleistocene.