16 research outputs found
Palaeoecological and genetic evidence for Neanderthal power locomotion as an adaptation to a woodland environment
The prevailing explanation for Neanderthal body form is the cold (glacial) adaptation hypothesis. However, palaeoecological associations appear to indicate a less cold woodland environment. Under such conditions, encounter and ambush (rather than pursuit) hunting e and thus muscular power and sprint (rather than endurance) capacity e would have been favoured. We hypothesise that the highly muscular Neanderthal body form reflects an adaptation to hunting conditions rather than cold, and here both review the palaeoecological evidence that they inhabited a mainly woodland environment, and present preliminary genetic analyses in support of this new hypothesis
Palynology and chronology of hyaena coprolites from the Piñar karstic Caves Las Ventanas and Carihuela, southern Spain
This paper presents pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves in southern Spain (Granada), with the aim of reconstructing the environmental conditions of these hominin sites. The LV coprolites are radiocarbon dated from c. 37,890 to 6980 cal yr BP, and the Car coprolites from c. 31,063 to 7861 cal yr BP. Overall, the palaeoecological scenario inferred from both coprolite series display similar patterns, with Pinus, Poaceae, and Artemisia as dominant during the full Pleistocene, and an important contribution of Quercus in the most recently dated coprolite samples. While the palynology is consistent with results of former investigations on the past environments in the region as obtained from other deposits (peat bogs, cave infills), the Late Glacial and Holocene chronology of several coprolites in both sites is in conflict with the generally accepted timing of extinction of Crocuta in western Europe. A discussion on the taphonomical processes and potential sources of carbon contamination of the radiocarbon samples is provided. The correlation between pollen from coprolites and from sedimentary records, and the paucity of the fossil bone record suggests nevertheless, that a late survival of Crocuta in southern Spain should not be categorically discarded
Pleistocene environments, climate, and human activity in Britain during Marine Isotope Stage 7: insights from Oak Tree Fields, Cerney Wick, Gloucestershire
Investigations at Oak Tree Fields, Cerney Wick, Gloucestershire, in western England have revealed a sequence of fluvial deposits dating from Marine Oxygen Isotope Stage (MIS) 7 to 5. At the base of the sequence, a series of gravel and sand facies were deposited, initially as part of a meandering river. Reductions in flow energy of the latter and avulsion led to the development of short-lived channels and episodic backwater environments, the deposits of which are recorded as Facies Associations 1–3. Poorly sorted, probably colluvial deposits formed beyond the limit of the channel (Facies Association 4). Mollusca, Coleoptera, plant macrofossils, pollen and vertebrates recovered from the channel facies indicate broadly similar climatic conditions throughout accretion. Temperature ranges derived from mutual climatic range analysis of the Coleoptera almost completely overlap with those of Cerney Wick at the present day, albeit that winters may have been cooler when the channel was active. Further, the floral and faunal data suggest that the meandering river flowed through an open grassland environment, the latter heavily grazed by large vertebrates, most notably mammoth. Most of the botanical and faunal remains, together with four optically stimulated luminescence (OSL) age estimates ranging from 225 ± 23 to 187 ± 19 ka, suggest correlation of the channel deposits with MIS 7. The basal deposits (Facies Association 1) yielded the majority of vertebrate remains and all the lithic artefacts, most of which seem likely to have travelled only a short distance. Although only a few artefacts were recovered, they add to the relatively limited evidence of human activity from the upper Thames. The channel deposits are overlain by sheet gravels (Facies Association 5) which are attributed to the Northmoor Member of the Upper Thames Formation. These were likely to have been deposited as bedload in a braided stream environment, while two OSL age estimates of 129 ± 14 and 112 ± 11 ka suggest accumulation during MIS 5
Diverse responses of common vole (Microtus arvalis) populations to Late Glacial and Early Holocene climate changes – Evidence from ancient DNA
The harsh climatic conditions during the Last Glacial Maximum (LGM) period have been considered the cause of local extinctions and major faunal reorganizations that took place at the end of the Pleistocene. Recent studies have shown, however, that in addition many of these ecological events were associated with abrupt climate changes during the so-called Late Glacial and the Pleistocene/Holocene transition. Here we used ancient DNA to investigate the impact of those changes on European populations of temperate vole species (Microtus arvalis). The genetic diversity of modern populations and the fossil record suggests that the species may have survived cold episodes, like LGM, not only in the traditional Mediterranean glacial refugia but also at higher latitudes in cryptic northern refugia located in Central France, the northern Alps as well as the Carpathians. However, the details of the post-glacial recolonization and the impact of the Late Glacial and Early Holocene climate changes on the evolutionary history of the common vole remains unclear. To address this issue, we analysed mtDNA cytochrome b sequences from more than one hundred common vole specimens from 36 paleontological and archaeological sites scattered across Europe. Our data suggest that populations from the European mid- and high latitudes suffered a local population extinction and contraction as a result of Late Glacial and Early Holocene climate and environmental changes. The recolonization of earlier abandoned areas took place in the Mid- to Late Holocene. In contrast, at low latitudes, in Northern Spain there was a continuity of common vole populations. This indicates different responses of common vole populations to climate and environmental changes across Europe and corroborates the hypothesis that abrupt changes, like those associated with Younger Dryas and the Pleistocene/Holocene transition, had a significant impact on populations at the mid- and high latitudes of Europe
Neandertal and Denisovan DNA from Pleistocene sediments.
Although a rich record of Pleistocene human-associated archaeological assemblages exists, the scarcity of hominin fossils often impedes the understanding of which hominins occupied a site. Using targeted enrichment of mitochondrial DNA we show that cave sediments represent a rich source of ancient mammalian DNA that often includes traces of hominin DNA, even at sites and in layers where no hominin remains have been discovered. By automation-assisted screening of numerous sediment samples we detect Neandertal DNA in eight archaeological layers from four caves in Eurasia. In Denisova Cave we retrieved Denisovan DNA in a Middle Pleistocene layer near the bottom of the stratigraphy. Our work opens the possibility to detect the presence of hominin groups at sites and in areas where no skeletal remains are found
Ancient DNA of narrow-headed vole reveal common features of the Late Pleistocene population dynamics in cold-adapted small mammals
The narrow-headed vole, collared lemming and common vole were the most abundant small mammal species across the Eurasian Late Pleistocene steppe-tundra environment. Previous ancient DNA studies of the collared lemming and common vole have revealed dynamic population histories shaped by climatic fluctuations. To investigate the extent to which species with similar adaptations share common evolutionary histories, we generated a dataset comprised the mitochondrial genomes of 139 ancient and 6 modern narrow-headed voles from several sites across Europe and northwestern Asia covering approximately the last 100 thousand years (kyr). We inferred Bayesian time-aware phylogenies using 11 radiocarbon-dated samples to calibrate the molecular clock. Divergence of the main mtDNA lineages across the three species occurred during marine isotope stages (MIS) 7 and MIS 5, suggesting a common response of species adapted to open habitat during interglacials. We identified several time-structured mtDNA lineages in European narrow-headed vole, suggesting lineage turnover. The timing of some of these turnovers was synchronous across the three species, allowing us to identify the main drivers of the Late Pleistocene dynamics of steppe- and cold-adapted species.NWOVI.C.191.070Human Origin
Faunal and human biogeography during the Terminal Pleistocene.
The evocative megafauna of the mammoth steppe, such as woolly mammoths and woolly rhinos, are part of a complex and changing faunal and environmental system. The dynamic processes leading to faunal change (including extinction) are currently not fully understood. In order to unravel these biogeographical processes, which may take decennia up to millennia, the latter part of the Pleistocene (60-10 thousand years ago) that involved large and irregular climate changes in Europe was investigated. This project aimed to gain better understanding of the biogeographical processes of the mammals in this period. This was done by collecting published data on faunal assemblages and their respective radiocarbon dates. There are differences in the accuracy and reliability of the radiocarbon dates. To separate these, this thesis presents a standardised way of auditing radiocarbon dates to improve the comparison of studies in Palaeolithic Europe. The changes in biogeographical ranges were studied based on the presence of mammal species throughout Europe. Species distribution modelling of current climatic niches provided a new quantifiable framework for defining the ecology of mammals in Europe today to enable the reconstruction of past environments. Based on this framework, this thesis investigated the non- analogue communities of the Late Pleistocene. The ecological niche models based on present-day distributions found that non-analogue combinations were unlikely in the past, although the data used may not reflect all climatic and biogeographic variability and so there were likely fleeting combinations of taxa not seen today. Finally, the most famous, extinct and therefore non-analogue, taxon was investigated in detail: the Neanderthal. The climatic niche of the Neanderthal was explored with climatic niche modelling. The models confirm the Neanderthal was a temperate adapted taxon that retreated to the southwest of Europe during MIS3. Furthermore, the climatic niche model shows a tentative link where the Greenland Stadials had a negative impact on the distribution of the projected climatic niche in both climatic and geographic space. This thesis therefore provides an integrated study with new frameworks and results on the biogeographic ranges of mammals in past environments, that are relevant for multiple disciplines such as archaeology, palaeontology, ecology and phylogeography
Archeologisch bureauonderzoek en inventariserend veldonderzoek, verkennende fase
In opdracht van Gebroeders Joh. Guijt Beheer BV heeft IDDS Archeologie in februari 2013 een archeologisch bureauonderzoek en een inventariserend veldonderzoek (IVO), verkennende fase, uitgevoerd aan de Ambachtsweg 32 in Katwijk, gemeente Katwijk. De aanleiding voor dit onderzoek is de bouw van een nieuw bedrijfspand.
Het bureauonderzoek wijst uit dat het plangebied in de restgeul van de Oude Rijn ligt, deze is ontstaan na het sluiten van de monding in het begin van de Late Middeleeuwen. Na het opvullen van de geul is het gebied waarschijnlijk gebruikt als weiland. Vervolgens is het terrein opgehoogd bij de aanleg van het bedrijventerrein ’t Heen.
De veldgegevens van het booronderzoek laten zien dat het plan inderdaad in de dichtgeslibde restgeul van de Oude Rijn ligt. Onder hoge stroomsnelheden is een zandpakket afgezet in de riviergeul. Na het opvullen van de geul met zand ontstond er een laagte die geleidelijk werd opgevuld met een kleipakket. In het noordwesten van het plangebied ontstond een oeverzone die begroeid is geraakt. Voorafgaand aan de aanleg van het bedrijventerrein is het hele gebied opgehoogd met ongeveer 1,0 m grof zand om het terrein te egaliseren en beter bebouwbaar te maken.
Voor zowel de zand- en kleipakketten die zijn afgezet door de riviergeul, geld een lage verwachting voor archeologische resten omdat het gebied onder water stond. Gedurende een lange periode, waarschijnlijk tussen ongeveer de 12e en 20e eeuw, was dit gebied nat tot zeer nat en daardoor alleen bruikbaar als weilanden zoals ook op basis van het bureauonderzoek werd verwacht. Het ophoogpakket is pas in de 20e eeuw aangebracht en heeft daarom geen archeologische verwachting.
Op basis van de resultaten van het inventariserend veldonderzoek wordt geadviseerd om geen vervolgonderzoek uit te laten voeren
Archeologisch bureauonderzoek
In opdracht van Van Oosten Groep heeft IDDS Archeologie in mei 2013 een archeologisch bureauonderzoek uitgevoerd voor de locatie Toonbeeld – Jan van Nassaustraat 6 in Castricum, gemeente Castricum. De aanleiding voor dit onderzoek is het opstellen van een voorontwerpbestemmingsplan, waarbij woningen zullen worden gerealiseerd. Graafwerkzaamheden in het plangebied van 3925 m2 ten behoeve van deze ontwikkeling zullen zorgen voor een bodemverstoring tot een vooralsnog onbekende diepte. Het gemeentelijk beleid schrijft voor dat bij ingrepen vanaf 500 m2 en dieper dan 0,4 m –mv archeologisch onderzoek verplicht is. Het doel van het bureauonderzoek is het opstellen van een gespecificeerde verwachting voor het plangebied. Dit gebeurt aan de hand van bestaande bronnen over bekende en verwachte archeologische waarden binnen het plangebied.
Uit het onderzoek is gebleken dat het plangebied in een gebied ligt waar de omstandigheden voor bewoning zeer ongunstig waren. Door de ligging van het plangebied in het estuarium van het Oer-IJ tot de Late IJzertijd geldt er in het plangebied een (zeer) lage verwachting voor resten van voor deze periode. Maar ook daarna bleef het landschap waar het plangebied deel van uitmaakte zeer nat en bleven de omstandigheden ongeschikt voor bewoning. Het is echter wel mogelijk om archeologische resten aan te treffen uit deze periode.
Het gebied is vermoedelijk in de Middeleeuwen ingericht als agrarisch gebied, waardoor de bovengrond licht is omgewerkt, maar waardoor er tevens geen resten uit deze periode worden verwacht. Moderne verstoringen in het plangebied zoals voor de aanleg van de huidige bebouwing reiken zeer waarschijnlijk tot in de natuurlijke IJ-afzettingen, waardoor deze lagen deels verstoord zijn.
De gemeente Castricum heeft besloten dat op basis van deze resultaten alsnog een Inventariserend Veldonderzoek, verkennende fase door middel van boringen uitgevoerd dient te worden in het plangebied
Archeologisch bureauonderzoek
IDDS Archeologie heeft in april 2013 een archeologisch bureauonderzoek uitgevoerd voor de Meerlaan, Hazepad en Dr. Van Noortlaan in Stompwijk, gemeente Leidschendam-Voorburg. Rioolwerkzaamheden aan de drie straten zijn de aanleiding voor dit onderzoek. Graafwerkzaamheden zullen zorgen voor een bodemverstoring tot een diepte van maximaal 2,05 m beneden maaiveld