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The early Pleistocene site of Barranco León (Guadix-Baza Basin, SE Spain), dated to 1.4 Ma (millions of years ago), records the oldest hominin occurrence in Western Europe, as evidenced by the discovery of one tooth and thousands of Mode 1 stone tools. In this paper a detailed analysis of the microvertebrate content of the D1 and D2 units from this site is presented. The early Pleistocene in the Guadix-Baza Basin is characterized by a sharp climatic deterioration, which possibly impeded the settlement of this region by the early hominin population from the southern Caucasus. Shortly afterwards, when the climatic conditions were again favorable, a hominin presence is suddenly evidenced at the units D1 and D2 of Barranco León. According to the microvertebrate analysis of these units, the mean annual temperature at the time of deposition was significantly higher than 13 °C, with prevalent humid conditions. However, although most of the species were inhabitants of water edges, an open landscape was present in the vicinity of the lake. The data reported here clearly support the idea that the early hominin occupation of Europe was strongly constrained by climatic and environmental conditions, rather than by physiography or cultural factors., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The process of learning requires morphological changes in the neuronal connections and the formation of new synapses. Due to the importance of memory and learning in our species, it has been suggested that the synaptic plasticity in a number of association areas is higher in the human brain than in other primates. Cortical neurons in mammals are characterized by higher metabolism, activity, and synaptic plasticity during development and the juvenile stage than in the adult. In Homo sapiens, brain development is retarded compared with other primates, especially in some association areas. These areas are characterized by the presence of neurons, which remain structurally immature throughout their lifespans and show an increase in the expression of the genes, which deal with metabolism and the activity and synaptic plasticity in adulthood. The retention of juvenile features in some adult neurons in our species has occurred in areas, which are related to episodic memory, planning, and social navigation. The increase of the aerobic metabolism in these neurons may lead, however, to higher levels of oxidative stress, therefore, favoring the development of neurodegenerative diseases which are exclusive, or almost exclusive, to humans, such as Alzheimer's disease., (Copyright © 2011 Wiley-Liss, Inc.)

Here we present the results of a study of the small mammal assemblage recovered from a now disappeared karstic fissure located in a quarry called 'Pedrera del Corral d'en Bruach'. The site was located at 330 m a.s.l. in the Garraf Massif, ca. 20 km south of Barcelona. An archaeological rescue excavation was conducted in 2006 by the Grup de Recerca del Quaternari, focusing on sieving the sediments that had accumulated at the foot of the quarry face. Fortunately, some faunal remains and sediment were recovered, which were later processed and sorted. Two hundred and seventy small mammal remains were identified at genus or species level, bringing to light 15 taxa. The assemblage is typical of the Mammal Neogene 17 (MN17) biozone, placing this site in the Gelasian stage of the Early Pleistocene. It is noteworthy that the first record of the glirid Glirulus pusillus in Iberia is documented. Based on the small mammals identified, the surrounding environment of the Garraf Massif is judged to have been characterised by open forest landscape and more humid environmental conditions than nowadays. Finally, the site provides a remarkable contribution to what is known of the Iberian small mammals of this time period. [ABSTRACT FROM AUTHOR]

In this paper, a new genus and species of arvicolid rodent is described from the late early Pleistocene levels of the sections of Fuente Nueva 3 (Guadix-Baza Basin, Granada, southern Iberian Peninsula), and Quibas (Murcia, southeastern Iberian Peninsula). The majority of Manchenomys n. gen. molars lacks roots, and the morphology of the first lower molar (m1) is simple, with a short and rounded anteroconid complex and widely confluent triangles four and five (T4 and T5) fields.Molar enamel is predominantly negatively differentiated (Mimomys-type). The third upper molar (M3) is also simple, with a short posterior cap. Manchenomys orcensis n. sp. is described from Fuente Nueva 3, and Mimomys oswaldoreigi Agustí, Castillo & Galobart, 1993 from Gilena 2 and Barranco de los Conejos is recombined as Manchenomys oswaldoreigi n. comb. The chronostratigraphic range of Manchenomys n. gen. covers the upper Matuyama geomagnetic chron, between 1.8 Ma (postOlduvai subchron) and 0.99 Ma (Jaramillo subchron). Manchenomys n. gen. was possibly derived from a local population of Mimomys tornensis Janossy & Meulen, 1975, an arvicolid species present in older early Pleistocene levels of Spain. [ABSTRACT FROM AUTHOR]

A new insular species of Paraethomys (Muridae, Rodentia) with medium-sized hypsodont teeth is described from the Zanclean of Mallorca (Balearic Islands, western Mediterranean). The m1 displays the most distinctive traits: hypsodonty, a high occurrence of an unusual anterior cingulum, a well-developed labial cingulum, high accessory labial cuspids resembling the Apodemus pattern and a funnel between c1 and the hypoconid. Paraethomys balearicus sp. nov. preserves traits close to those present in the earliest populations of Paraethomys meini from the upper Turolian, such as a developed posterior spur on t3 in the M1, a connection between t4 and t8 in the M1, a narrow connection between t6 and t9 in the M1 and the occasional presence of an individualized t9 and a t12 in some M2s. The relationship between the new taxon and its direct mainland ancestor gives additional support to a Messinian origin for the so-called Myotragus fauna, which became isolated after the refilling of the Mediterranean Sea 5.33 Ma ago. The absence of Paraethomys in other known younger Mallorcan sites suggests that its extinction most probably occurred at an indeterminate time during the Pliocene Epoch. [ABSTRACT FROM AUTHOR]

A new insular giant species of Apocricetus (M1 length > 4.22 mm, upper teeth row length > 10.90 mm) is described from dental, mandibular and cranial material recovered at the Na Burguesa-1 site (Mallorca, Balearic Islands, western Mediterranean), a Zanclean palaeokarst deposit chronologically close to the refilling of the Mediterranean after the Messinian Salinity Crisis. Apocricetus darderi sp. nov. shows a close relationship with the mainland species A. alberti (MN13), an Iberian taxon, from which it differs in size, the presence of labial and lingual anterolophids in m1, triple anterolophulids frequently developed, a reduced anterosinusid in m2 and m3 and, occasionally, the presence of an ectomesolophid in m3. Apocricetus darderi sp. nov. becomes the first endemic Balearic mammal that can be confidently assigned as having a direct mainland relative, providing the first solid palaeontological evidence of a Messinian origin for the Plio-Pleistocene fauna of Mallorca. Tragomys macpheei from the Caló den Rafelino site (Early Pliocene, probably late MN14 or early MN15) displays a peculiar selenodont teeth pattern and a high degree of hypsodonty, and is considered to be either a direct descendant of Apocricetus darderi sp. nov. or a sister taxon derived from a common ancestor. [ABSTRACT FROM AUTHOR]

The Neogene Fortuna Basin (Murcia Region, SE Spain) is rich in microvertebrate sites. Its continental sections include localities extended from the middle Turolian (MN12) to the early Ruscinian (MN14). However, there are few works dealing with the taxonomy of these fossil assemblages. In this paper we provide a complete taxonomic study of the rodents and insectivores from three levels (ROM-2B, ROM-2C and ROM-3A) within the Romerales section. We infer a late Turolian age (late Messinian) for these levels, among which the richest and most diverse level is ROM-C, including at least 11 different taxa. In addition, the paleoecological analysis of these fossil assemblages suggests the dominance of open herbaceous meadows under temperate climate during the formation of these sites, with a slight decrease in temperature and humidity from ROM-2B to ROM-2C. [ABSTRACT FROM PUBLISHER]

In this paper, we synthesize sedimentological, magnetostratigraphic and paleontological data from the continental vertebrate site of Puerto de la Cadena (Murcia, SE Spain), in order to clarify its age. The study site is located on the northern edge of the Carrascoy mountain range, in the upper part of the Cigarrón Unit. The end-Messinian discontinuity has been detected at the base of this unit, which indicates it has an early Pliocene age. Abundant remains of small and large vertebrates, including rodents, lagomorphs, primates, carnivorans, perissodactyls, artiodactyls, proboscideans, testudines, squamats, and crocodiles, have been found in this area. Some of these elements are of African origin, such as Debruijnimys sp., Macaca sp., and Sivatherium cf. hendeyi , and their presence is related to the Messinian Salinity Crisis. In addition, remains found at this site verify the persistence of Crocodylia in the European record beyond the late Miocene. The association includes typical elements of the early Ruscinian terrestrial record (MN14), like Apocricetus cf. barrierei , Sivatherium , Gazella aff. baturra , and Hipparion fissurae . The Puerto de la Cadena site is located in a reversed geomagnetic chron that has been correlated with C3n.3r (from 4.997 to 4.896 Ma). According to this correlation, the MN13/MN14 boundary has a minimum age of 4.9 Ma. [ABSTRACT FROM AUTHOR]

Small mammals (insectivores, rodents, and lagomorphs) from Dmanisi are here reviewed for the first time and used as a tool for paleoenvironmental proxies. The small mammal faunal list is composed of shrews (Beremendia fissidens, cf. Beremendia minor, Crocidura kornfeldi), hamsters (Cricetulus sp., Allocricetus bursae), gerbils (Parameriones aff. obeidiyensis), murids (Apodemus cf. atavus), arvicolids (Mimomys pliocaenicus , Mimomys aff. pusillus), and pikas (Ochotona sp.). A paleoenvironmental reconstruction based on the habitat weighting method has been applied to the rodent assemblage. According to this method, the most common elements indicate an open-dry habitat (36.5%), followed by water edge (25.7%) and rocky (21.0%) elements. Open-wet (15.5%) and woodland elements (1.3%) are rare. Therefore, the habitat occupied by the hominids of Dmanisi was characterized by the prevalence of arid conditions, from steppe or semi-desert to open Mediterranean forest, with stony or rocky substrate and bushy areas. The presence of permanent aquatic environments is also documented. From a biogeographic point of view, the small mammal community from Dmanisi is composed mainly by Western or Central Asian elements, with a poor representation of European elements (Mimomys , Apodemus). It is concluded that Dmanisi hominins most possibly had ecological requirements which were different from those of the Early Pleistocene hominins from Western Europe, which settled on wetter habitats. It could be also possible that Dmanisi hominins entered Southern Caucasus at an interglacial phase before the deposition of the Dmanisi site. [ABSTRACT FROM AUTHOR]

The study of small mammals may provide important chronological and paleoenvironmental information in the archaeological context of a particular geographic region. Few specific studies have been conducted on fossil small mammals in North Africa, especially for the late Quaternary period. However, the Holocene site of the Guenfouda Cave, situated in the region of Oujda (Eastern Morocco), provides new data on the chronology and the paleoecology of this period. The small-mammal association from Guenfouda comprises at least 12 taxa: two soricomorphs (Crocidura russulaandC. whitakeri), one macroscelian (Elephantulus rozeti), two bats (Myotis blythiiandRhinolophus hipposideros) and seven rodents (Mus spretus,Meriones shawii,Apodemus sylvaticus,Dipodillus campestris,Eliomyssp.,Atlantoxerus getulusandCtenodactylussp.). The absence in our assemblage of species recently introduced to Morocco, such asMus musculusandRattusspp. (R. rattusandR. norvegicus), allows us to establish relative data for the beginning of the Holocene (Neolithic) for the Guenfouda Cave in accordance with the archaeological remains recovered. From a paleoecological point of view, the small-mammal assemblage shows a mosaic landscape dominated by a Mediterranean climate similar to today but slightly drier, comparable to that found in other sites in North Africa with an analogous chronology. [ABSTRACT FROM AUTHOR]

In this article, a new genus, Frontanyamys, is defined based on the new species F. russelli. The genus is recorded from the lower Upper Eocene (Bartonian) beds AT Sant Jaume de Frontanya (NE Spain). This genus shows clear affinities with the previously described genera Zamoramys, Remys and Pairomys. They are therefore assembled in the family Remyidae (new rank). The remyids are characterised by the precocious development of high-crowned molars and retain a morphologically primitive dental pattern. The oldest remyids are found in the middle Eocene of Spain ( Zamoramys) and are probably derived from a morphologically primitive protrogomorph rodent such as Corbarimys paisi. The last representatives of the family such as Remys and Pairomys developed a fully lophodont dental pattern. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a survey on the Messinian section of Can Vilella, in the intramontane basin of La Cerdanya (Pyrenees) is presented. The mammalian association, composed of insectivores, rodents and lagomorphs, is a very atypical one compared to other late Turolian (Messinian) assemblages from Spain and Western Europe, including Central European taxa such as Epimeriones aff. austriacus, which are very rare or absent in the late Miocene from Spain and, even, from Western Europe. The palynological record indicates a riparian forest with abundance of marshy herbs. A magnetostratigraphic study reveals a reverse polarity span for most of the section, whereas in the upper part normal polarities are found. According to the magnetobiostratigraphic correlation established in other basins, the normal geomagnetic episode at the top of the section should correspond either to chron C3An.2n or C3An.1n. In any case, the Can Vilella association clearly predates the onset of the Messinian Salinity Crisis (MSC) in the Mediterranean. This means that the set of climatic and palaeogeographic events associated with the MSC cannot account for the anomalous association from Can Vilella. A discussion as to whether an altitudinal component could be responsible for such an anomaly is undertaken. [Copyright &y& Elsevier]

Abstract: The thick continental record in the Fortuna Basin enables the to establishment of an accurate chronology for the main mammalian events in the Western Mediterranean between 7.6 and 4.5my, thus covering the whole Messinian interval. A first mammalian event at about 7.2my records a significant turnover in the muroid rodent associations. A second mammalian event is characterized by the dispersal of the murid Paraethomys and a number of large mammals which indicates a first African–Iberian exchange at about 6.2my. Finally, a third mammalian event dated between 5.9 and 5.3my involved the dispersal from northern Africa of the gerbil rodents. This event is clearly associated with the Mediterranean sea level drop following the Messinian Salinity Crisis. [Copyright &y& Elsevier]

Mimomys savini is a very important arvicoline as it represents a useful biochronological tool in the study of the first human arrivals in Europe and its expansion across the continent. To date, evolution studies on this species have focused on its size changes and the loss of ancestral characteristics. This work sheds further light on the evolution of this taxon, through a study of the morphological changes in its first lower molar, using, for the first time, 2-D geometric morphometrics techniques based on landmark configurations. To do this, we have analyzed M. savini remains spanning 1.4 to 0.78 Ma from the Gran Dolina site (Sierra de Atapuerca, Spain), Barranco León site (Orce, Spain), and Barranc de la Boella site (Tarragona, Spain). Our results show a set of occlusal surface shape differences between the more recent and older populations. The oldest populations are characterized by a more developed lingual re-entrant angle 4 (LRA4); a less developed buccal re-entrant angle 3 (BRA3); a narrower lingual re-entrant angle 1 (LRA1); and a wider neck of the head of the anteroconid complex (ACC) than in more recent populations. Moreover, despite the increase in m1 length and width during the evolution of M. savini , it seems that the size of the occlusal surface decreased (maybe as a consequence of shape changes, such as neck width or the size of re-entrant angles). Finally, the shape and size comparisons of the populations studied reinforces previously proposed chronologies for Barranc de la Boella, and suggests a site age similar to that of Gran Dolina (section TD6 -TD5). • The morphological evolution of Mimomys savini has been reviewed using 2DGM. • A new set of differences between older and younger populations of M. savini has been found. • New data indicate that unit II from Barranc de la Boella site has a similar chronology to Gran Dolina site section TD5-TD6. [ABSTRACT FROM AUTHOR]