Early Pleistocene Age Research Articles

Quaternary environment and climate change reconstruction from geochemical and geoarchaeological evidences of paleosols in east-central Barind, NW Bangladesh

This research focuses on analyzing paleosols, major and trace element geochemistry, organic carbon levels, and geo-archaeological aspects of Quaternary deposits investigated in two sedimentary successions located in the east-central Barind region of NW Bangladesh. Several factors that influence the paleosol development can be used to decipher the paleoenvironment and paleoclimatic conditions of the study area. Sedimentary succession of the studied sections have been grouped into two broad categories i.e., Gray unit/Newer Alluvium (NA) of Late Holocene and Red unit/Older Alluvium (OA) of Early Pleistocene age. Some geoarchaeological evidences have been found at the bottom of the gray unit and the top of the red unit in Durgadaha (DD) section indicating the existence of paleo-settlement at about ∼1300 years BP. The age is determined by the relative dating of several artifacts found at the paleo-settlement surface. Interpretation of several field characteristics and geochemical parameters i.e., clayeyness, salinization, base loss, calcification, leaching (Ba/Sr), aeolian input (Zr/Al), CIA, CIW, CIA-K, etc. revealed that the paleosols in gray unit are weakly developed; whereas, paleosols in red unit are relatively moderate, strong to very strongly developed. In the red unit, the MAP and MAT range from 1000 ± 181 mm to 1478 ± 181 mm and 9° ± 4.4°–14° ± 4.4 °C respectively. On the other hand, MAT ranges from 23.1° ± 0.6 °C to 28.3° ± 0.6 °C in gray unit paleosols. Depending on the depositional pattern and estimated MAT, five short-term climatic cycles (i.e., alternating phases of dry and wet) have been recognized in gray/newer alluvium units during the last 1300 years. The demise of paleo settlement (1300 years BP) due to the abrupt climatic change towards a dry and cooler phase where the MAT was estimated as 23.1° ± 0.6° which is at least 3 °C lower than the present. This study also revealed that the estimated MAP and MAT are more analogous to paleoclimatic records of the Asian regions.

Geochronological advances in human and proboscideans first arrival date in the Philippines archipelago (Cagayan valley, Luzon Island)

The Paleolithic site of Kalinga, in the Cagayan River Basin (Luzon Island), has recorded the oldest known traces of human occupation of the Philippine archipelago dated at 709 ± 68 ka. The island of Luzon is further known for its endemic Hominin Homo luzonensis (Callao cave) recently dated at 134 ± 14 ka, which makes it the oldest human remains in the Philippines.The present study provides new chronological data on the Kalinga site and surrounding localities on the left bank of the Cagayan Valley and tackles the question over the geochronology of the human settlement of the basin. Following the discovery of some abundant paleontological remains and lithic artefacts on surface, several excavations took place since the 1970s. In 2014, new research in the area by our team on a site named Kalinga led to the recovery of hundreds of undisturbed archaeological remains (lithic tools and butchery marks). Apart from the early Middle Pleistocene ages obtained for the Kalinga site, the geochronology of the area is still largely unknown. Through the use of ESR on bleached quartz and 40Ar/39Ar single crystal laser fusion on plagioclase dating methods, the chronology of four archaeological sequences has been here constrained for the first time. Our results highlight a human occupation presence between 796 ± 70 ka and 273 ± 20 ka reducing the chronological gap between Kalinga site and Callao Cave, placing the Cagayan basin as a cornerstone to better understand the human arrival in insular Asia.

Re-examining the earliest evidence of human presence in western Europe: New dating results from Pirro Nord (Italy)

We present the results of the first dating study of site P13 at Pirro Nord, Italy, which documents some of the earliest evidence for hominin presence in western Europe. Our multi-technique dating approach is based on a combination of palaeomagnetism, electron spin resonance (ESR), thermally-transferred optically stimulated luminescence (TT-OSL) and combined U-series/ESR applied to both fossil material and host sediment. It provides ages ranging from 627 ± 59 to 1006 ± 126 ka and clustering around 0.8 Ma. One additional fossil tooth collected from the nearby P10 site also returns an age within this range. Ordinarily, this outcome would naturally lend itself to the straightforward conclusion that Pirro Nord has a late Early Pleistocene age of ∼0.8 Ma. However, this interpretation is complicated by the fact that these numerical dating results are in contradiction with the biochronological evidence, which suggests a much older age on the order of 1.3–1.7 Ma. Consequently, we explore the various potential sources of bias that could have influenced the numerical dating methods and the biochronological inferences. In particular, the critical evaluation of the palaeomagnetic data available for various sites belonging to the younger Colle Curti Faunal Unit (FU) indicates that there is non-negligible age uncertainty on the allegedly minimum age of ∼1.1 Ma traditionally assigned to the Pirro FU. Moreover, while the combined U-series/ESR dataset could accommodate an older age for the fossil remains if uranium uptake in the dental tissues occurred relatively rapidly before the closure of the system (CSUS model), the ages obtained from the two semi-independent quartz dating methods (ESR and TT-OSL) both appear to indicate that the sediment was last exposed to sunlight about 0.8 Ma. This disparity opens up the possibility that the sediment and fossil assemblage may not be coeval. In other words, it is possible that the fossil remains may have been reworked into younger deposits that entered the karst about 0.8 Ma. Though feasible from a karst sedimentary dynamics perspective, this hypothesis is not consistent with previous taphonomic studies that indicate an absence of evidence for fossil reworking after entering the karst. At the very least, our dating results indicate that site formation processes at Pirro Nord site P13 are more complex than previously considered.

Facies analysis, biostratigraphy, and provenance of the late Neogene Seulimeum Formation, Northwest Aceh basin, Sumatra (Indonesia)

A sedimentological, biostratigraphic, and petrographical investigation was conducted on exposed sedimentary rocks in the Seulimeum Formation in the Northwest Aceh Basin, Sumatra. Sedimentary facies analysis suggests a deep-marine depositional environment consists of an inner fan, middle fan, and outer fan to basin plain deposits. New foraminiferal data designated a late Miocene to early Pleistocene age for the studied rock unit, equivalent to N17 to N21 zone, with paleobathymetry in the bathyal environment. Petrographically, the sandstone of the Seulimeum Formation is included as subarkose, sublithic arenite, and lithic arenite, or classified as litho-quartzose, feldspatho-litho-quartzose, and litho-feldspatho-quartzose. Provenance analysis suggests that the origin of the sandstones is from the arc orogen sources. Furthermore, it is concluded that the development of the GSF zone in the late Neogene controls the formation of the deep-marine depositional setting. The west-south-west part of the fault is the footwall part (the Barisan Mountains), as the main high area of sedimentary source material consisting dominantly of the Woyla Group, with some contributions from Bentaro volcanic and Paleogene to early Neogene sediments. Our findings also suggest that the beginning of the Great Sumatran Fault, which corresponds with the uplift of the Barisan Mountains in the northern part of Sumatra, took place in the late Miocene, between 8.6 and 5.9 Ma.

The earliest European Acheulean: new insights into the large shaped tools from the late Early Pleistocene site of Barranc de la Boella (Tarragona, Spain)

Since the oldest known Acheulean lithic techno-typological features in Europe were reported at the site of Barranc de la Boella (Tarragona, Spain), continuous fieldwork has been conducted there in archeological deposits of the late Early Pleistocene age (0.99–0.78 Ma). As a result, excavations in two of the three open-air localities have significantly expanded the collection of lithic and faunal remains, allowing us to make progress in the interpretation of the hominin behaviors in an open-air fluvial-deltaic sedimentary environment. This includes examples of cumulative palimpsests, such as those found at the locality of La Mina, in which hominins only had a minimal role as modifying agents, as well as the extraordinary mammoth butchery site recorded at the Pit 1 locality. The aim of this paper is to present a comprehensive update of the collection of large shaped tools and to assess its significance in the framework of the earliest occurrence of the Acheulean in Europe. This cultural entity is increasingly well-documented for the early Middle Pleistocene, but very little is known about its presence in Europe before the Brunhes–Matuyama boundary. Large shaped tools appear in the three localities explored in the Unit II of Barranc de la Boella, including choppers (unifacial and bifacial) and standard Acheulean forms, such as picks, knives, and cleaver-like forms. Techno-typological and morphometrical analyses revealed a basic heavy-duty component obtained through simple shaping sequences coupled with significantly more elaborate tools produced on various large blanks (cobbles, slabs, or flakes). The complete bifacial and bilateral shapings have yet to be documented, but the present specific tool assemblage attests to the Early Acheulean technological threshold. Hence, the archaeological data from Barranc de la Boella provide insights into the first appearance of the Acheulean technology in Europe and add critical information to the debate on the technological variability of the Early Pleistocene hominin occupation of the continent. The results of this study revealed a technological assemblage unique in the known late Early Pleistocene archeological record from Europe, different from the rest of ancient Acheulean sites in this continent, which are dated at the Middle Pleistocene. This lends support to the hypothesis that Barranc de la Boella may represent a previously unrecognized Early Acheulean dispersion out of Africa connected to its first evidence at the gates of Eurasia, potentially moving over the northern Mediterranean coastal road to reach Western Europe.

Environmental Reconstruction from the Identification of Magnetic Minerals in the Upper Sedimentary Infill of the Gran Dolina Cave (Burgos, Spain)

The cave system in the Sierra de Atapuerca holds one of the most important archaeological sites for the understanding of early human occupation in Europe. Among the different cavities and galleries, the Gran Dolina cave yielded a new hominin species coined as Homo antecessor of an Early Pleistocene age. Encouraged by our previous results in Gran Dolina, we carried out a study to extend and deepen our rockmagnetic investigation of the paleoenvironmental reconstruction of the upper Gran Dolina cave based on experiments that include composition, relative concentration, and grain size of the magnetic iron oxides present in the sediments. Based on the rockmagnetic experiments, we identified magnetite, hematite, goethite, and possibly maghemite in changeable amounts along the profile, which allows us to complement the existing shortage in the literature on the palaeoenvironmental reconstruction of the site. We tentatively interpret the rockmagnetic changes recorded in the cave sediments in terms of glacial/interglacial conditions, furnishing the base for a better understanding for the formation conditions of this unprecedented archaeological site.

History of Polish Canidae (Carnivora, Mammalia) and Their Biochronological Implications on the Eurasian Background.

The remains of 12 canid species that date back ca. 4.9 myr have been found at 116 paleontological localities. Among these localities, eight are dated to the Pliocene age, 12 are dated to the Early Pleistocene age, 12 are from the Middle Pleistocene age, while the most numerous group includes 84 sites from the Late Pleistocene-Holocene age. Some, especially older forms such as Eucyon odessanus and Nyctereutes donnezani, have only been found at single sites, while the remains of species from the genus Lycaon, Canis and Vulpes have been recorded at numerous sites from the last 2 myr. Ancient canids such as Eucyon and Nyctereutes had already vanished from Poland in the Earliest Pleistocene, between 2.5 and 2.2 myr ago. Poland's extant canid fauna is characterised by the presence of two new species, which spread into the territory due to a human introduction (Nyctereutes procyonoides) or natural expansion (Canis aureus). Research indicates a strong competition between dogs, especially between Lycaon, Canis and Cuon, with a strong lycaon-limiting effect on the wolf between 2.5 and 0.4 myr ago. After the extinction of Lycaon lycaonoides, Canis lupus evolved rapidly, increasing in number and size, and taking over the niche occupied by Lycaon. In order to reduce competition, the body size of Cuon alpinus gradually reduced, and it became an animal adapted to the forest, highland and mountain environments. Generally, the history of canids in Poland is similar to that known of Eurasia with some noteworthy events, such as the early occurrence of Canis cf. etruscus from Węże 2 (2.9-2.6 myr ago), Lycaon falconeri from Rębielice Królewskie 1A or one of the latest occurrences of L. lycaonoides from Draby 3 (430-370 kyr). Predominantly lowland or upland in the southern part and devoid of significant ecological barriers, Poland is also an important migration corridor in the East-West system. This 500-600 km wide corridor was the Asian gateway to Europe, from where species of an eastern origin penetrated the continent's interior. In colder periods, it was in turn a region through which boreal species or those associated with the mammoth steppe retreated.

A complex record of last interglacial sea-level history and paleozoogeography, Santa Rosa Island, Channel Islands National Park, California, USA

Studies of marine terraces and their fossils can yield important information about sea level history, tectonic uplift rates, and paleozoogeography, but some aspects of terrace history, particularly with regard to their fossil record, are not clearly understood. Marine terraces are well preserved on Santa Rosa Island, California, and the island is situated near a major marine faunal boundary. Two prominent low-elevation terraces record the ∼80 ka (marine isotope stage [MIS] 5a) and ∼120 ka (MIS 5e) high-sea stands, based on U-series dating of fossil corals and aminostratigraphic correlation to dated localities elsewhere in California and Baja California. Low uplift rates are implied by an interpretation of these ages, along with their elevations. The fossil assemblage from the ∼120 ka (2nd) terrace contains a number of northern, cool-water species, along with several southern, warm-water species, a classic example of what has been called a thermally anomalous fauna. Low uplift rates in the late Pleistocene, combined with glacial isostatic adjustment (GIA) processes, could have resulted in reoccupation of the ∼120 ka (MIS 5e), 2nd terrace during the ∼100 ka (MIS 5c) high-sea stand, explaining the mix of warm-water (∼120 ka?) and cool-water (∼100 ka?) fossils in the terrace deposits. In addition, however, sea surface temperature (SST) variability during MIS 5e may have been a contributing factor, given that Santa Rosa Island is bathed at times by the cold California Current with its upwelling and at other times is subject to El Niño warm waters, evident in the Holocene SST record. Study of an older, high-elevation marine terrace on the western part of Santa Rosa Island shows more obvious evidence of fossil mixing. Strontium isotope ages span a large range, from ∼2.3 Ma to ∼0.91 Ma. These analyses indicate an age range of ∼500 ka at one locality and ∼ 600 ka at another locality, interpreted to be due to terrace reoccupation and fossil reworking. Consideration of elevations and ages here also yield low, long-term uplift rates, which in part explains the potential for terrace reoccupation in the early Pleistocene. In addition, however, early Pleistocene glacial-interglacial cycles were of much shorter duration, linked to the ∼41 ka obliquity cycle of orbital forcing, a factor that would also enhance terrace reoccupation in regions of low uplift rate. It is likely that other Pacific Coast marine terrace localities of early Pleistocene age, in areas with low uplift rates, also have evidence of fossil mixing from these processes, an hypothesis that can be tested in future studies.

Flow regime evolution of a major cave system in the Eastern Alps (Hirlatzhöhle, Dachstein)

The 116 km-long and 1560 m-deep Hirlatzhöhle is one of the major cave systems in the Northern Calcareous Alps (NCA; Austria). It is located in the NW part of the Dachstein, an extensive karst massif encompassing 576 km² with its highest point at 2995 m a.s.l. In contrast to most other caves in the NCA, Hirlatzhöhle comprises old (epi)phreatic passages located up to 1 km above the base level as well as two modern major drainage systems. The aim of this study is to define the palaeo- and the active flow conditions in combination with speleogenesis, and the age of the cave levels of Hirlatzhöhle. We use morphological as well as sedimentological studies and correlations with other caves. Another difference from cave systems in the NCA is that the majority of passages in Hirlatzhöhle are not developed within the so-called Giant Cave Level between 1200 and 1800 m a.s.l., but deeper between 800 and 1300 m. Most parts of Hirlatzhöhle developed under epiphreatic conditions as indicated by rills and condensation corrosion cupolas, which is the case for much other cave systems in the NCA. In contrast, paragenetic features like canyons and ceiling channels are relatively rare as are insoluble sediments. Elongated scallops indicate that flow velocities were high and abrasive sediments were abundant. Opposite to the nearby Dachstein-Mammuthöhle and other caves east of it that show a west-directed palaeo-flow, scallops in Hirlatzhöhle indicate a NE-directed palaeo-flow and an autogenic recharge. Modern drainage is autogenic and N- to NE-directed as well. Even though burial age dating did not give reasonable results for Hirlatzhöhle yet, the correlation with other adjacent caves suggests a Late Pliocene to Early Pleistocene age of the main palaeo-phreatic level. This is supported by an infinite U-Th age (>0.6 Ma) of a flowstone.

An Early Pleistocene interglacial deposit at Pingorsuit, North‐West Greenland

At the Pingorsuit Glacier in North‐West Greenland, an organic‐rich deposit that had recently emerged from the retreating ice cap was discovered at an elevation of 480 m above sea level. This paper reports on macrofossil analyses of a coarse detritus gyttja and peaty soil, which occurred beneath a thin cover of till and glacifluvial deposits. The sediments contained remains of vascular plants, mosses, beetles, caddisflies, midges, bryozoans, sponges and other invertebrates. The flora includes black spruce, tree birch, boreal shrubs and wetland and aquatic taxa, which shows that mires, lakes and ponds were present in the area. We describe a new extinct waterwort species Elatine odgaardii. The fossils were deposited in a boreal environment with a mean July air temperature that was at least 9 °C higher than at present. The fossil assemblages show strong similarities with others from Greenland that have been assigned an Early Pleistocene age, and we suggest a similar age for the sediments found at the margin of the Pingorsuit Glacier.At the Pingorsuit Glacier in North‐West Greenland, an organic‐rich deposit was discovered at an elevation of 480 m above sea level. The sediments contained remains of vascular plants, mosses, beetles, caddisflies, midges, bryozoans, sponges and other invertebrates. The fossils were deposited in a boreal environment with a mean July air temperature that was at least 9 °C higher than at present.

Sulfuric acid speleogenesis and surface landform evolution along the Vienna Basin Transfer Fault: Plavecký Karst, Slovakia

Hypogene caves in the Plavecký hradný vrch Hill (Western Slovakia, Central Europe) were formed by waters ascending along faults in fractured Triassic carbonates related to the horst-graben structure at the contact of the Malé Karpaty Mountains and the NE part of the Vienna Basin. The Plavecká jaskyňa and Pec caves mostly contain horizontal passages and chambers with flat corrosion bedrock floors, fissure discharge feeders, wall water-table notches, replacement pockets, as well as a few other speleogens associated with sulfuric acid speleogenesis. The low-temperature sulfuric acid development phases of the Plavecká Jaskyňa are also indicated by the presence of sulfate minerals (i.e., gypsum and jarosite).Subaerial calcite popcorn rims were precipitated from water condensation at the edges of feeding fissures that were still active as thermal vents when the water table dropped. Hydrogen sulfide involved in the sulfuric acid speleogenesis was likely derived from anhydrites and/or hydrocarbon reservoirs with sulfate-saline connate waters in the fill of the adjacent Vienna Basin. It ascended to the surface along deep-rooted sub-vertical fault zones at the contact of the Vienna Basin with neighboring mountains. Three cave levels at 295 to 283 m asl in the Pec Cave, and five levels at 225 to 214 m asl in the Plavecká jaskyňa corresponded to phases of stable local erosional base levels in the bordering part of the Vienna Basin, most likely during periods of strongly decelerated and/or interrupted subsidence. Cave levels separated by vertical differences of only a few meters may also be related to the Pleistocene climatic cycles. The subhorizontal parts of the Pec Cave are probably of late Early Pleistocene age (˃0.99–1.07 Ma?). The two highest levels of the Plavecká jaskyňa developed during the early Middle Pleistocene (˃600 ka). Fine-grained sediments in the passage at 225 m asl with normal magnetic polarity contain jarosite. The middle level of the Plavecká jaskyňa at 220 m asl was formed in the mid-Middle Pleistocene, while the lower and lowermost levels formed in the late Middle Pleistocene (˃270 ka). The water table in the lowermost cave level probably dropped after the tectonic reactivation of the Podmalokarpatská zníženina Depression just in the front of a marginal horst structure of the Malé Karpaty Mountains.

New palaeontological evidence suggests an early Middle Pleistocene age for the lower levels of Sun Hole Cave, Cheddar, Somerset, UK

Sun Hole, a small fissure cave on the north side of Cheddar Gorge, Somerset, is best known as the site where late Upper Palaeolithic artefacts are associated with human and other mammal remains that immediately pre-date the Lateglacial interstadial. These remains from the upper levels (Unit I) overlie sediments (Unit II) that are thought to have accumulated during a full glacial period, below which are sediments (Unit III) attributed to an interglacial stage. The extinct land snail Retinella (Lyrodiscus) sp., which in Britain was only known from the Hoxnian Stage, had previously been recovered from Unit III. The interglacial at the base of the sequence was therefore assigned to the Hoxnian Stage (Marine Isotope Stage (MIS) 11, 424–374 kyr). Here we provide additional analyses of samples from Unit III, which as well as containing further Retinella (Lyrodiscus), also yielded a specimen of Monachoides incarnatus, its first record from the British Pleistocene. An associated assemblage of small mammals included a few that are rare in the British Pleistocene, such as birch mouse (Sicista cf. betulina) and garden dormouse (Eliomys quercinus). The vole Lasiopodomys gregaloides and the shrew Sorex (Drepanosorex) savini do not occur as late as the Hoxnian and therefore suggest an older age in the early Middle Pleistocene. The record from Sun Hole therefore has parallels with the well-known sequence from the upper Calcareous Member in the nearby cavern system at Westbury-sub-Mendip.

Karakterisasi dan Klasifikasi Ultisols Yang Berkembang dari Dua Bahan Induk di Kabupaten Serang, Provinsi Banten

The effort to utilize the soils optimally, especially Ultisols, requires an appropriate understanding related to their characteristics. The characteristics of Ultisols are sturdily influenced by soil-forming factors, viz. climate, parent material, pedogenic age and topography. The purposes of this study were to determine the chemical, physical, mineralogical characteristics and soil development classification level of Ultisol from two different types of parent rock. This research was conducted in Kampungbaru Village, Petir District and Sukalaksana Village, Curug District, in Serang Regency, Banten Province. These two villages represented different parent materials, namely andesite lava parent material of Holocene age (Kampungbaru Village) and tuff dacite parent material of early Pleistocene age (Sukalaksana Village). The research method was descriptive, comparative and survey. Soil classification was based on the Soil Survey Staff. The results showed that Ultisols developed from dacite tuff and andesite lava did not show contrasting differences in soil properties. The level of weathering of the two pedons was at the senile stage and the level of soil development of the two pedons was at the argillic stage. The soil classification of Kampungbaru pedon was Typic Palehumults, very fine, kaolinitic, isohyperthermic, while the Sukalaksana pedons was Arenic Paleudults, fine, kaolinitic, isohyperthermic

Fossil wood diversity record from Merangin region, Jambi, Indonesia

Merangin is a region in Jambi province, Indonesia, which well-known for its geodiversity. As part of geodiversity, fossil woods play an important role in reconstructing the ancient trees during geological history. Since the study on fossil wood origin Merangin Regency, Jambi, is still limited, this study was conducted to determine fossil wood identity through anatomical features observation and estimate the age of fossil wood samples through geological analysis. The anatomical characteristics were observed using a light microscope to identify the botanical identity of the discovered fossil wood samples. The description of anatomical features refered to the IAWA list of microscopic features for hardwood identification. The result showed that all fossil woods had similarities with the modern wood from the Dipterocarpaceae family, namely Dryobalanoxylon sp. (Kamper), Hopenium sp. (Merawan/Hopea), Shoreoxylon sp. (Meranti), and Cotylelobioxylon sp. (Giam/Resak). These fossil woods were found in different estimated geological age namely Late Permian/Perem age (254-252 million years old), Late Miocene age (7.24-5.33 million years old); Late Pliocene to Early Pleistocene age (3.60-2.58 million years old); and Holocene age (11,700 years old - present). Another approach by using Global Mapper 11 resulted that all the fossil woods were estimated grown in Permian age (290 - 250 million years).

A Messinian (latest Miocene) occurrence for Albanerpeton Estes & Hoffstetter, 1976 (Lissamphibia: Albanerpetontidae) at Moncucco Torinese, Piedmont Basin, northwestern Italy, and a review of the European Cenozoic record for albanerpetontids

Albanerpetontids are an extinct clade of superficially salamander-like lissamphibians that range from the Middle Jurassic (Bathonian)-Early Pleistocene and have a primarily Laurasian distribution. The best Cenozoic record for the clade is in Europe, where two species in the type genus AlbanerpetonEstes & Hoffstetter, 1976 occur in over 40 localities of early Oligocene-Early Pleistocene age in Austria, Czech Republic, France, Germany, Hungary, Italy, and Serbia. From the post-evaporitic Messinian (5.41-5.33 Ma or latest Miocene) succession at Moncucco Torinese, in the Piedmont Basin, northwestern Italy, here we describe isolated albanerpetontid jaws and vertebrae referable to A. pannonicumVenczel & Gardner, 2005. This Italian occurrence extends the temporal record for A. pannonicum from the Early Pleistocene and Pliocene back into the latest Miocene and it narrows the temporal gap between that species and its European congener, A. inexpectatumEstes & Hoffstetter, 1976 (early Oligocene-late Miocene).

A Pliocene\u2013Pleistocene continental biota from Venezuela

The Pliocene–Pleistocene transition in the Neotropics is poorly understood despite the major climatic changes that occurred at the onset of the Quaternary. The San Gregorio Formation, the younger unit of the Urumaco Sequence, preserves a fauna that documents this critical transition. We report stingrays, freshwater bony fishes, amphibians, crocodiles, lizards, snakes, aquatic and terrestrial turtles, and mammals. A total of 49 taxa are reported from the Vergel Member (late Pliocene) and nine taxa from the Cocuiza Member (Early Pleistocene), with 28 and 18 taxa reported for the first time in the Urumaco sequence and Venezuela, respectively. Our findings include the first fossil record of the freshwater fishes Megaleporinus, Schizodon, Amblydoras, Scorpiodoras, and the pipesnake Anilius scytale, all from Pliocene strata. The late Pliocene and Early Pleistocene ages proposed here for the Vergel and Cocuiza members, respectively, are supported by their stratigraphic position, palynology, nannoplankton, and 86Sr/88Sr dating. Mammals from the Vergel Member are associated with the first major pulse of the Great American Biotic Interchange. In contrast to the dry conditions prevailing today, the San Gregorio Formation documents mixed open grassland/forest areas surrounding permanent freshwater systems, following the isolation of the northern South American basin from western Amazonia. These findings support the hypothesis that range contraction of many taxa to their current distribution in northern South America occurred rapidly during at least the last 1.5 million years.

Pliocene to Holocene chronostratigraphy and palaeoenvironmental records from cave sediments: Račiška pečina section (SW Slovenia)

The sedimentological record in the Račiška pečina cave sediment sequence is one of the best-preserved cave records of palaeoenvironmental changes for the last 3.4 Ma. However, as it is typical for cave terrestrial records, it contains many hiatuses in sedimentation. The section study helped to change the state of knowledge and understanding of the long-lasting deposition characteristics in the caves and provided enormous data on environmental changes over time. In the sequence are by magnetostratigraphy well recorded Pliocene/Pleistocene transition at 2.59 Ma, the Matuyama/Brunhes boundary at 0.773 Ma, and the presence of Olduvai subchron between 1.78 and 1.925 Ma. Records of small mammals from the lower part of the section (a molar of Apodemus cf. atavus and dental fragments of Borsodia sp., and Pliomys sp.) suggest MN17 age, Clethrionomys cf. glareolus from the upper part suggests the Late Early or Middle Pleistocene age. Also worth mentioning are records of snail shells Aegopinella sp. and a troglobiont snail Zospeum sp. In the upper part of the section Ursus ex gr. spelaeus was confirmed in the yellow clay layer older than ~72 ka, and soot material at the top of the section was radiocarbon dated on ~11 ka, ~9 ka, and ~3 ka. A detailed chronology of the Račiška pečina section based on magnetostratigraphy and isotopic oxygen stratigraphy was created and correlated with palaeontological, U-series, and radiocarbon results. Before the hiatus 2.6-2.5 Ma ago, the oxygen record was mainly shaped by regional Mediterranean Sea factors. After this boundary, the RP record becomes more similar to the LR04 stack, implying the increased influence of Atlantic Ocean factors.

Multi-Method Luminescence Dating of Old Fluvial Sediments from Northern Tian Shan, China

At the eastern tip of Anjihai anticline on the northern piedmont of Tian Shan (northwest China), deformed fluvial deposits have recorded active folding since the Pleistocene, but the absence of accurate ages makes it difficult to evaluate the anticline's shortening rate. Geological studies ascribed the fluvial strata to the early Pleistocene, which poses potential challenges for luminescence dating. In this study, multi-methods luminescence dating was applied to a fluvial sand sample taken from the sandy bed of the deformed basal strata. Single grain post-Infrared Infrared Stimulated Luminescence (pIRIR) and multiple-aliquot-regenerative (MAR) dose along with multiple-elevated-temperature pIRIR (MET-pIRIR) procedures were applied to determine the paleodose of the sample. The methodological uncertainties, such as thermal transfer and initial sensitivity change, were treated by increasing the test dose and performing dose recovery test. With consideration of the potential partial bleaching and anomalous fading, various statistical metrics were applied to the D<sub>e</sub> values determined by using the single grain pIRIR<sub>225</sub>, single grain pIRIR<sub>290</sub> and MAR-MET-pIRIR<sub>290</sub> signals. The minimum age model (MAM) D<sub>e</sub> values are 11% – 17% lower than the central age model (CAM) D<sub>e</sub> values in general, and the MAM D<sub>e</sub> values determined by the single grain pIRIR procedures are underestimated by more than 40% when compared with those determined by MAR-MET-pIRIR<sub>290</sub> procedure. The MAM MAR-MET-pIRIR<sub>290</sub> D<sub>e</sub> of 811 ± 44 Gy results in a burial age of 284 ka for the basal deformed fluvial strata, which is much younger than the proposed early Pleistocene age.

The amphibians and reptiles from the Early Pleistocene of Coste San Giacomo (Anagni Basin, Italy)

ABSTRACT The site of Coste San Giacomo, in the Anagni Basin, is renowned for its mammal fauna of Early Pleistocene (Gelasian) age, including 32 taxa of small and large mammals. Adding to these, a small amount of remains of amphibians and reptiles was also recovered during recent excavations focused on collecting small vertebrates as well. The analysis of these remains resulted in the identification of a total of at least six different taxa: three anurans (Bufonidae indet., Pelophylax sp., and Rana sp.) and three reptiles (Lacertidae indet., Pseudopus sp., and Natrix sp.). This assemblage is comprised of taxa that are common in the Italian Quaternary, but also presents the first occurrence of the large anguid Pseudopus from the Apennine Peninsula in this period. On the whole, the herpetofauna indicates the presence of humid conditions in CSG at the moment of deposition of the bone bed that yielded the vertebrate remains.

Fossil bear material from the oldest deposits in the Jasna Strzegowska cave (Silesia, southern Poland)

Fossil bear material from the lowermost deposits of the Jasna Strzegowska cave is described and its taxonomic status assessed. Comparison with bear remains from other Early and early Middle Pleistocene localities of Eurasia shows the presence of two bear species: Ursus etruscus and U. deningeri , based on morphological and size characters of the teeth and postcranial bones. The teeth of U. deningeri from the Jasna Strzegowska cave are larger, wider and have much more complicated occlusal surfaces when compared with the teeth of U. etruscus . Both bear species are characterized by relatively short and robust metapodials, although those of U. etruscus are on average less massive. Some differences in muscle attachments and articular surfaces have also been found. Metapodials of primitive arctoid bears, that co-occurred with U. etruscus and U. deningeri , are much longer and slimmer. U. etruscus and U. deningeri probably did not live in the Jasna Strzegowska cave at the same time. Based on its time range in Eurasia and morphological characteristics, the age of U. etruscus is estimated as Early Pleistocene, between 1.8–1.3 Ma. This is its first description from Poland, and the remains described are in size and morphology indistinguishable from material from other European localities. For U. deningeri , an early Middle Pleistocene age is suggested.