Quaternary Sites Research Articles

The youngest occurrence of Hexaprotodon Falconer and Cautley, 1836 (Hippopotamidae, Mammalia) from South Asia with a discussion on its extinction

The earliest hippopotamid fossils from the Indian Subcontinent come from the Miocene of the Siwalik Group. South Asian hippopotamidae are represented by the genus Hexaprotodon, and remains of these hippos are commonly found in Neogene and Quaternary sites. Here we report on the first directly dated specimen of Hexaprotodon sp. from the Narmada Valley of Central India and its associated paleoecological implications. The specimen, an upper right canine fragment, was dated to 16,467–15,660 cal BP using accelerator mass spectrometry radiocarbon dating method. This individual lived during Heinrich Event 1, a particularly arid period. Isotopes from dental enamel revealed this animal to have lived in a savanna environment, and likely experienced a shortage of water. Using other dated remains of Hexaprotodon from the Indian Subcontinent, we developed a tentative extinction chronology, which showed that Hexaprotodon likely survived into the Early Holocene. We hypothesize that a combination of climatic stress and anthropogenic impacts would have caused the species’ eventual extinction.

Fossil lizards and worm lizards (Reptilia, Squamata) from the Neogene and Quaternary of Europe: an overview

Lizards were and still are an important component of the European herpetofauna. The modern European lizard fauna started to set up in the Miocene and a rich fossil record is known from Neogene and Quaternary sites. At least 12 lizard and worm lizard families are represented in the European fossil record of the last 23 Ma. The record comprises more than 3000 occurrences from more than 800 localities, mainly of Miocene and Pleistocene age. By the beginning of the Neogene, a marked faunistic change is detectable compared to the lizard fossil record of Palaeogene Europe. This change is reflected by other squamates as well and might be related to an environmental deterioration occurring roughly at the Oligocene/Miocene boundary. Nevertheless, the diversity was still rather high in the Neogene and started to decrease with the onset of the Quaternary glacial cycles. This led to the current impoverished lizard fauna, with the southward range shrinking of the most thermophilic taxa (e.g., agamids, amphisbaenians) and the local disappearance of other groups (e.g., varanids). Our overview of the known fossil record of European Neogene and Quaternary lizards and worm lizards highlighted a substantial number of either unpublished or poorly known occurrences often referred to wastebasket taxa. A proper study of these and other remains, as well as a better sampling of poorly explored time ranges (e.g., Pliocene, Holocene), is needed and would be of utmost importance to better understand the evolutionary history of these reptiles in Europe.

Low-level doping of nitrogen to multilayered graphene by chemical vapor deposition of methane including melamine vapor

Growth of graphene doped with the low level of nitrogen is carried out on the copper foil by conventional chemical vapor deposition. Melamine is used as nitrogen source. Melamine vapor is generated by heating and carried by an argon flow (carrier flow) to a main flow of Ar including methane. Ratio of the number of molecules, melamine/methane, is controlled by changing the mixing rate of the carrier flow and the main flow. Measurements of Raman scattering, X-ray photoelectron spectroscopy, ultraviolet–visible spectroscopy and sheet resistance clarify the feature of prepared sample. At low melamine/methane ratio in the order of 10−3, quaternary N doped graphene is grown. Then the growth of pyridinic N doped graphene is going to start as increasing the melamine/methane ratio in the order of 10−2. Magnitude of the sheet resistance per one graphene layer decreases by ~ 75% when the nitrogen is in the quaternary site, while it increases twice or more when the pyridine-like configuration increases.

Diversification dynamics, species sorting, and changes in the functional diversity of marine benthic gastropods during the Pliocene-Quaternary at temperate western South America.

Functional diversity based on species traits is a powerful tool to investigate how changes in species richness and composition affect ecosystem functioning. However, studies aimed at understanding changes in functional diversity over large temporal and spatial scales are still scant. Here we evaluate the combined effect of diversification and species sorting on functional diversity of fossil marine gastropods during the Pliocene-Quaternary transition in the Pacific coast of South America. We analyzed a total of 172 species in 29 Pliocene and 97 Quaternary sites. Each species was characterized according to six functional traits: body size, feeding type, mobility, attachment, life-habit, and larval mode. Functional diversity was estimated according to four indexes (functional richness, evenness, divergence and dispersion) based on functional traits measured. Extrapolated species richness showed a slight yet not significant decrease from the Pliocene to the Quaternary despite the fact that a large faunal turnover took place; furthermore, a large extinction of Pliocene species (61–76%) was followed by a high pulse of appearances (49–56%) during the Quaternary. Three out of four indices of functional diversity (evenness, divergence and dispersion) increased significantly towards the Quaternary which is more than expected under a random turnover of species. The increase in functional diversity is associated with a loss of large-sized carnivore forms, which tended to be replaced by small-sized grazers. Hence, this trait-selective species turnover, even in the absence of significant changes in species richness, likely had a large effect and has shaped the functional diversity of present-day assemblages.

Theoretical study of the Pb adsorption on Ni, Cr, Fe surfaces and on Ni based alloys

Adsorption of Pb atoms on the Ni(111), Ni(100), Fe(110), and Cr(110) metallic surfaces was studied theoretically within an ab initio density functional theory approach (DFT). (√3×√3)R30° super structures for Ni(111), and (2×2) for the other surfaces, corresponding to the saturation state, were considered. The preferred adsorption sites are found to be ternary sites for Ni(111), Fe(110), Cr(110) and quaternary sites for Ni(100). Adsorption on Fe and Cr is less exothermic than on Ni, by 0.16 and 0.33eV/mol respectively. Adsorption on model surfaces of Ni based alloys was also investigated. It was found that the energy of adsorption depends mostly on the chemical composition of the ternary site, and can be described by a linear combination of the energies of adsorption on the pure metals. The nature of the second nearest neighbour of the adsorbed Pb atom has no significant influence on the adsorption energy. Average energies of adsorption were calculated in two cases: the limit of low coverage, and the saturation. The energies of adsorption of Pb at saturation on nickel base alloy surface representative of alloy 600 (Ni-15Cr-8Fe) and alloy 690 (Ni-30Cr-8Fe) were calculated to be 0.07 and 0.11eV lower than on pure Ni respectively.

A tale of two gorges: Late Quaternary site formation and surface dynamics in the Mula basin (Murcia, Spain)

We present a case-study in Palaeolithic archaeology focusing on formation processes at cave- and rock-shelter-sites in a Mediterranean context and on the correlation between site deposits, Quaternary surface sediments and the morphology of the surrounding land. We study three sites located in the basin of River Mula (Murcia, Spain): the cave-site of Cueva Antón and the rock-shelters of Finca Doña Martina and Abrigo de la Boja, in the Rambla Perea valley. They are examined through an integrated geoarchaeological approach that takes into account geomorphological, stratigraphic and soil micromorphological data. The three sites are found within a short distance and cover similar time spans within the Upper Pleistocene but have different formations and show distinct degrees of preservation of the archaeological record. Cueva Antón features a densely-stratified, mostly alluvial succession, with excellent preservation of stratigraphic layout and sedimentary facies. The succession represents a well-preserved record of past activity of the River Mula and can be correlated to its open-air alluvial system. The Rambla Perea sites, despite their immediate vicinity, underwent distinct formation dynamics, with a complex interaction among the site deposits and the hillslope along which they are found, and exhibit different degrees of preservation of archaeological layers and features. We summarise the evidence from these sites and then discuss its implications for site formation, for the preservation of the archaeological record and for the correlation between the ‘inside’ (the archaeological successions preserved within caves and in rock-shelters) and the ‘outside’ (the geomorphological setting of the land and the evolution of Quaternary surface dynamics through time).

One pot synthesis of chitosan grafted quaternized resin for the removal of nitrate and phosphate from aqueous solution

The present study deals with the synthesis of chitosan quaternized resin for efficient removal of nitrate and phosphate from aqueous solution. The resin was characterized with FTIR, SEM with EDX and XRD. Batch method was carried out to optimize various parameters such as contact time, initial concentration of nitrate and phosphate, dosage, pH, co-anions and temperature on the adsorption capacity of the adsorbent. The adsorption process illustrated that the Freundlich isotherm and the pseudo-second order are the best fitted models for the sorption of both anions. The respective negative values of ΔH° and ΔG° revealed that the adsorption of both the anions were exothermic and spontaneous. The removal efficiency of nitrate and phosphate on chitosan quaternized resin were 78% and 90% respectively with 0.1g of adsorbent and the initial concentration as 100mg/L. Nitrate and phosphate anions adsorbed effectively on chitosan quaternized resin by replacing Cl− ions from quaternary site through electrostatic attraction as well as ion-exchange mechanism. Hydrogen bonding also played important role in adsorption process. Even after 7th regeneration cycle the adsorbent retained its adsorption capacity as 23.7mg/g and 30.4mg/g for both nitrate and phosphate respectively.

Beavers (Castoridae, Rodentia, Mammalia) from the Quaternary sites of the Sierra de Atapuerca, in Burgos, Spain

The Eurasian beaver, Castor fiber is known from the Pleistocene in Europe, although there are references to the presence of the genus Castor since the Miocene, ca. 10 Ma. Beavers are present in the Iberian Peninsula since the Pliocene, though the first appearance of Castor fiber took place in the Early Pleistocene levels of the localities of the Sierra de Atapuerca, where the fossil beaver remains are found in the lower levels of Sima del Elefante and Gran Dolina (Early Pleistocene), Galería de las Estatuas (Late Pleistocene) and Portalón (Holocene). The presence of fossil beavers suggests humid and mild climatic conditions in the Early Pleistocene levels of Gran Dolina and Sima del Elefante. During the Middle Pleistocene, although conditions for beavers seemed favourable, they disappeared from Atapuerca, appearing again during the Late Pleistocene and the Holocene.

Working with the Public: How an Unusual Museum Enquiry Turned into Travels Through Time and Space

Museum enquiries offer a unique opportunity to engage on a one-to-one level with members of the public. This paper covers an unusual enquiry from 2013 of an unknown tooth that was brought into Plymouth City Museum and Art Gallery for identification. We highlight how museum enquiries can engage with members of the public by involving them directly with original scientific research. The tooth was found in a garden in Plymouth with no associated data of about where it originated. We identified the tooth, and the enquirer researched the history of the house. The tooth gave the appearance of a sub-fossil so with the large number of Quaternary sites in Plymouth, together with the identification of the previous owner on the site, there were valid reasons to undertake testing of the tooth to determine its origin. Strontium (Sr) isotope analysis of the tooth was carried out to determine if the tooth was British and radiocarbon dating was undertaken to work out the age of the tooth. The 87Sr /86Sr of the leopard tooth gave a value of 0.716131, with Sr concentrations at 568ppm. This is a high concentration of Sr ppm relative to other British data, suggesting a non-British origin. The radiocarbon measurement was 187 ± 24 years BP (University of Oxford Radiocarbon Accelerator Unit reference OxA-30390). This places the tooth not in the Pleistocene, but between 1739 and 1787 AD. The site where the tooth was discovered was owned by the brother of Linnaeus Tripe who travelled across India and Burma. We argue that the results of this study demonstrate that this leopard tooth was originally from India or Burma, and brought into Britain by Tripe. A correction article relating to the radiocarbon dates included in this publication can be found here: http://dx.doi.org/10.5334/oq.aj

Fossil bats from the Late Pleistocene site of the Aguilón P7 Cave (Zaragoza, Spain)

Bats (Chiroptera, Mammalia) are a valuable and independent source of palaeoenvironmental information in Quaternary sites because bat assemblages are not necessarily produced by the same processes as those of other small mammals. Here, we report a small collection of bats (MNI 15) from a cave infill of the Aguilón P7 (AGP-7) site (Zaragoza, Spain) dated Late Pleistocene (MIS 3). This is one of the rare localities south of the Ebro River (right bank) with Neanderthal tracks; therefore, the palaeoenvironmental data provided here may help us to understand Neanderthal history. Nine bat taxa were identified, viz. Rhinolophus ferumequinum, R. hipposideros, Myotis gr. myotis/blythii, M. cf. bechsteinii, M. emarginatus, M. daubentonii, Plecotus gr. auritus/austriacus, Hipsugo savii vel. Pipistrellus kuhlii/nathusii, and Miniopterus schreibersii. The presence of a high number of yearlings of the former four species suggests the presence of breeding colonies. The surprisingly high diversity of the sample indicates a variegated vegetation cover and relatively high humidity for the MIS 3 stage in the region.

Avian remains from the Upper Pleistocene (MIS3) site of Aguilón P-7, south of the Ebro River, Spain

Aves are represented by abundant fossil remains in Quaternary sites. Birds are well adapted to the environment they inhabit, so they make very good paleoenvironmental indicators for Quaternary sites. Here we analyse the avian remains from the Late Pleistocene (probably MIS3) site of Aguilón P-7 (AGP-7). The Pleistocene sediments fill up a shallow cave, which is located in the Zaragozan part of the Iberian Range, 55 km south of the city of Zaragoza. We have for the first time provided a taxonomic and taphonomic study of the avian assemblage of AGP-7, as well as a preliminary paleoenvironmental analysis based on these data. Nine avian taxa have been identified: Galliformes indet., Lagopus sp., Aquila chrysaetos, Gyps fulvus, Passeridae indet., Anthus sp., Prunella modularis,Sturnus cf. unicolor and Corvus monedula. The taphonomic analysis did not provide conclusive information. However, it suggests an accumulation of uneaten food remains by diurnal birds of prey. The identified taxa currently inhabit the Iberian Peninsula, populating woodland environments with rocky areas. They are found in areas with an oceanic climate, in contrast to the Mediterranean climate that now prevails in Aguilón.

Empirical Site Response and Comparison with Measured Site Conditions at ANSS Sites in the Vicinity of Reno, Nevada

We empirically evaluate spectral amplification relative to a nearby rock site at 18 Advanced National Seismic System strong‐motion stations within the basin containing the urban areas of Reno and Sparks, Nevada. The near‐surface site conditions have a strong effect on ground motion, which is clearly demonstrated through analysis of weak motion. The study uses multiple regional earthquake events of varying azimuth. Averages of these empirical amplifications, grouped by generalized geological formations (volcanic rock, Pliocene and early to mid‐Quaternary sediments, and younger Quaternary sedimentary sites), show dependence on the geology. However, when the stations are grouped according to V S 30 values, the mean amplifications are more distinct, indicating that V S 30 is a more useful predictor of amplification for the Reno–Sparks, Nevada, urban area. Spectral amplifications computed from ground motions of the local Mogul, Nevada, 2008 earthquake swarm ( M L 0.6–4.7; Anderson et al. , 2009) have similar spectral shapes for 8 of the 12 stations where comparisons could be made, but the absolute amplitudes are slightly inconsistent. Four stations show unexplained peaks in the amplitude spectral ratios from the mainshock ground motions. The comparisons verify that multiple regional ground motions can be used to obtain relative site‐response amplification functions for seismic‐hazard applications, but the discrepancies are a reminder that directional effects contribute uncertainty to the amplification functions. Online Material: Tables describing earthquakes recorded in the vicinity of Reno, Nevada, and figures of the Fourier spectral ratios (FSRs) and of the amplitude and basin depth relationships.

An evolving database for Quaternary aminostratigraphy

Amino acid racemization (AAR) dating methods have been used since the mid-1960s. Since that time, information technologies have evolved as AAR laboratories have worked to appropriately catalog sample collections and analyses. The University of Delaware AAR Database (UDAARDB) is a database of AAR and other geochronological data from coastal Quaternary sites in North and South America that has been in development for over 25years. In that time, database and software platforms have changed and a concerted effort has been made to digitize legacy data for preservation and to make these data available for future use. To ensure data preservation, all or part of UDAARDB is redundantly hosted at three institutions as data files and maps. Furthermore, the flexible nature of accessing the data (i.e., as online maps and common format data files) helps to maintain a public presence and, therefore, assists in their preservation.

Present and Norse Greenlandic hayfields – Insect assemblages and human impact in southern Greenland

This study uses new data on insect biodiversity from a modern sheep farm environment in southern Greenland, and compares the results with fossil assemblages from the same region and other relevant sites in Greenland. The study was conducted on sheep farms at Tasiusaq and Qorlortup Itinnera in southern Greenland (61°N, 45°W). Data have also been drawn from 17 Quaternary and archaeological sites from Greenland with an emphasis on Norse insect assemblages from the same area. Species diversity and abundance of Coleoptera from the modern samples were relatively low, while Hemiptera were dominant in all habitats sampled around the hayfields. The first local extinctions in the natural beetle fauna appear with the initiation of Norse settlement. The diversity of Coleoptera in the modern samples is lower compared with the Norse faunas, and this could partly be a result of mechanised agriculture. The Hemiptera demonstrate the exact opposite pattern. The modern samples include a similar range of Hemiptera species to their Norse equivalent, although the intensification in grass production is evident in the modern faunas. The increase of diversity in Hemiptera coincides with Landnám, with four additional species recorded from the Norse assemblages; the hemipterous faunas provide a signal for haymaking in the fossil record of Greenland.

Taxonomy and paleoecology of fossil Bovidae (Mammalia, Artiodactyla) from the Kibish Formation, southern Ethiopia: Implications for dietary change, biogeography, and the structure of the living bovid faunas of East Africa

The Kibish Formation of southern Ethiopia has yielded the earliest fossils of Homo sapiens, ca. 196ka, and has thus figured prominently in discussions of the origins of modern humans. Here we describe the fossil Bovidae from the Kibish Formation, a record that spans the late Middle Pleistocene to the early to mid-Holocene, and reconstruct aspects of their dietary ecology using mesowear analyses. All of the Kibish bovids represent extant taxa with the exception of the extinct blesbok-like alcelaphin Damaliscus hypsodon; extinct arid-adapted forms Syncerus antiquus and Megalotragus, common in other Late Quaternary sites, are notably absent. Mesowear of the Kibish bovids suggests that the Late Quaternary specimens were characterized by diets with considerably more abrasion-dominated wear relative to their extant conspecifics. Finally, the Kibish record provides supporting evidence for recent phylogeographic hypotheses by demonstrating significant range expansions of Aepyceros melampus, Connochaetes taurinus, Hippotragus equinus, and, to a lesser extent, Kobus kob in the late Middle Pleistocene through the early to mid-Holocene coincident with humid phases that punctuated dry spells of the Late Quaternary.

A novel fabrication of a polymeric ionic liquid hybrid film modified electrode and its successful application to the electrogeneration of a superoxide anion in aqueous media.

A novel polymeric ionic liquid hybrid film-modified electrode, in which the electrode surface is coated with a hydrophobic hybrid material composed of an ionene polymer with quaternary ammonium sites in its polymeric backbone and ionic liquids, was fabricated by electropolymerization of N,N-dimethylaniline in a hydrophobic ionic liquid, which can be applied for the electrogeneration of a superoxide anion via one-electron reduction of O2 in aqueous media.

Instant luminescence chronologies? High resolution luminescence profiles using a portable luminescence reader

Establishing a robust chronology is fundamental to most palaeoenvironmental studies. However, the number and positioning of dated points is critical. Using a portable luminescence reader, it is possible to rapidly generate high resolution down core relative age profiles. Profiles of portable luminescence data from two coastal dunes were evaluated and compared with the results of particle size analysis, stratigraphy, and an independent historical chronology. Results show that, even in young samples, portable luminescence data is dominated by an age related signal which in homogeneous sediment need not be corrected for moisture, feldspar content changes or grain size. Profiles therefore provide relative chronologies from which accumulation phases can be established, and from which better targeted sampling and comparison to other sites could be undertaken. Even though they do not provide instant absolute chronologies, field-based portable luminescence profiling of Late Quaternary sites hold much potential to improve the resultant chronologies.

New Computational Insights to Describe the Oxygen Reduction Reaction on Graphene Containing Multiple Nitrogen Functional Groups

The development of new cathodes for low temperature fuel cells has spurred the research of low cost and durable materials, particularly non-noble materials displaying a similar performance as Platinum [1]. To this concern, metal-free nitrogen doped graphene containing various nitrogen functional groups (quaternary, pyrollic, and pyridinic species) have been found to facilitate the electrocatalysis of Oxygen Reduction Reaction (ORR) as in traditional Pt-based catalysts [2]. Atomistic simulations have been conducted to describe the ORR mechanism on different carbonaceous materials. However, these analysis have mostly been dedicated to Platinum (Pt)-based catalysts, and single nitrogen groups on Carbon nanotubes (CNTs) [3]. Thus, this study is oriented to account for the quantum mechanics interactions arising during the ORR on N-doped graphene structures containing pyridinic, pyrollic and quaternary species. Density functional theory is utilized to compute the Gibbs energy of the adsorbed intermediates and chemical species (e.g. H, OOH, H2O2, OH, O, and O2) formed during the course of the ORR mechanism. The calculations evaluate the scale-up of the cluster in order to screen out local effects due to dimensions, and the reactivity of the aforementioned species on all possible catalytic sites (refer to positions a,b,c, adjacent to C1, C2, PR, PD in figure 1a). It was found that H, OOH, OH, O, and O2 preferentially chemisorb or physorb on the quaternary site C1-a, whereas H2O2 species reacts favorably on C2-b. Keywords: ORR, DFT, Pyridinic, Pyrollic, and Quaternary Species.[1] Gong, K.; Du, F.; Xia, Z.; Durstock, M.; Dai, L., Science 2009, 323, 760.[2] Biddinger, E.; Deak, D. v.; Ozkan, U., Top. Catal. 2009, 52, 1566.[3] Hyman, M. P.; Medlin, J. W., J. Phys. Chem. B 2006, 110, 15338–15344.

Quaternary perspectives on the diversity of land snail assemblages from northwestern Europe

The land snail assemblages in NW Europe exhibit marked gradients in diversity related to both latitude and longitude. These gradients, in turn, are linked to regional differences in temperature and moisture, although other non-climatic factors may be involved. Such diversity patterns have been described for the modern land snail faunas of NW Europe, especially those that inhabit forest. Here we provide an historical perspective on the development and composition of comparable land snail assemblages from various interglacials from the Middle and Late Pleistocene, and from the Holocene. We review the land snail assemblages from tufa sequences, which provide the best faunal records for each of the temperate periods. Data from 32 Quaternary sites in 7 NW European countries are considered. Assemblages from ‘forest optima’ of Pleistocene interglacial periods are richer in species compared with those from the Holocene. Correspondence analysis (CA) of data from 25 Quaternary sites in the regions where both Pleistocene and Holocene sites occur (i.e. southern England, northern France and Germany) resulted in a geographical separation of the assemblages into a western and eastern group. CA on each geographical group resulted in chronological divisions separating Pleistocene sites from the Holocene sequences. This separation results from the occurrence of numerous Central and Eastern European species in the Pleistocene faunas, whereas Holocene assemblages are characterized by species with mostly Western and Northern European modern ranges. This difference appears to reflect climatic influences, rather than resulting from anthropogenic effects. CA of 19 Holocene tufas produced geographical clusters clearly related to their position on a west-east gradient, presumably linked to some effect of ‘continentality’. During the mid Holocene, the diversity of forest snails from tufas in southern England exceeded the totals from the richest calcareous woodland sites in the region today. Further work is needed to establish whether this pattern holds for other regions of NW Europe.

Avian Remains from Marmot Cave, A New Site in the North‐West Altai, Siberia

ABSTRACTAvian remains from a new quaternary site (Marmot Cave) in the NW Altai, Siberia, located very close to the famous Denisova Cave, have been studied. The fauna from Marmot Cave includes 19 extant taxa, three of which were not reported previously from Denisova Cave. Taphonomic analysis of the bird bones from the new site indicates a mixed origin for the material. The largest portion of bones evidently represents remains not eaten by large falcons, while a small part of the sample may be the prey of the Golden Eagle. Bones of the Black Grouse are of anthropogenic origin and apparently were brought to Marmot Cave from the human settlement of Denisova Cave. The faunal composition suggests a Holocene age for the sediments of Marmot Cave, which is in contradiction with data from mammal remains. Copyright © 2013 John Wiley & Sons, Ltd.