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2. Comments to the paper “A 10Be chronology of the Esmark Moraine and Lysefjorden region, southwestern Norway: Evidence for coeval glacier resurgence in both polar hemispheres during the Antarctic Cold Reversal” by Aron E. Putnam, George H. Denton and Joerg M. Schaefer
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Mangerud, Jan, primary, Svendsen, John Inge, additional, and Briner, Jason P., additional
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- 2024
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3. Editorial comment on Hill and Easterla's (2023) paper on Smilodon fatalis
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Schreve, Danielle, primary and Hillaire-Marcel, Claude, additional
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- 2023
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4. Why has my paper been rejected without scientific review?
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- 2022
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5. Exploring former subglacial Hodgson Lake, Antarctica Paper I: site description, geomorphology and limnology
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Hodgson, Dominic A., Roberts, Stephen J., Bentley, Michael J., Smith, James A., Johnson, Joanne S., Verleyen, Elie, Vyverman, Wim, Hodson, Andy J., Leng, Melanie J., Cziferszky, Andreas, Fox, Adrian J., and Sanderson, David C.W.
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- 2009
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6. Exploring former subglacial Hodgson Lake, Antarctica. Paper II: palaeolimnology
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Hodgson, Dominic A., Roberts, Stephen J., Bentley, Michael J., Carmichael, Emma L., Smith, James A., Verleyen, Elie, Vyverman, Wim, Geissler, Paul, Leng, Melanie J., and Sanderson, David C.W.
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- 2009
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7. Why has my paper been rejected without scientific review?
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- 2022
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8. Archives of humans, environments and their interactions – papers in honour of Professor C. Neil Roberts and Professor Henry F. Lamb
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Warren J. Eastwood, Melanie J. Leng, and Matthew Jones
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010506 paleontology ,Archeology ,Global and Planetary Change ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Geology ,01 natural sciences ,Honour ,Geography ,Archaeology ,Ecology, Evolution, Behavior and Systematics ,Classics ,0105 earth and related environmental sciences ,media_common - Abstract
This special issue of QSR comprises a series of papers written to celebrate the careers of Neil Roberts (Professor of Physical Geography) and Henry Lamb (Professor of Quaternary Science), as they retire from full-time posts. Both Henry's and Neil's research careers have been exceptional, marked by novel, cutting-edge research of the very highest quality within cognate disciplines and which address the big questions in Quaternary Science. Both have promoted the importance of environmental change; Neil primarily in the ‘sea in the middle of the earth’ (i.e., the lands bordering the Mediterranean) and Henry in tropical east Africa and Morocco. Both have made immense contributions to our understanding of global change in the Quaternary and have been instrumental in raising the discipline to new levels of scientific rigour. They both have CVs listing over 100 publications and still counting. This volume is an opportunity to celebrate their work and say thanks.
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- 2018
9. Archives of humans, environments and their interactions – papers in honour of Professor C. Neil Roberts and Professor Henry F. Lamb
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Leng, Melanie J., primary, Eastwood, Warren, additional, and Jones, Matthew D., additional
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- 2018
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10. Exploring former subglacial Hodgson Lake, Antarctica. Paper II: palaeolimnology
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Stephen Roberts, James Smith, Melanie J. Leng, David C.W. Sanderson, Dominic A. Hodgson, Elie Verleyen, Paul Geissler, Emma L. Carmichael, Wim Vyverman, and Michael J. Bentley
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Archeology ,Global and Planetary Change ,geography ,Provenance ,geography.geographical_feature_category ,Antarctic ice sheet ,Sediment ,Geology ,Glacier ,law.invention ,Sedimentary depositional environment ,Paleontology ,law ,Radiocarbon dating ,Ice sheet ,Ecology, Evolution, Behavior and Systematics ,Holocene - Abstract
Direct exploration of subglacial lakes buried deep under the Antarctic Ice Sheet has yet to be achieved. However, at retreating margins of the ice sheet, there are a number of locations where former subglacial lakes are emerging from under the ice but remain perennially ice covered. One of these lakes, Hodgson Lake (72°00.549′S, 068°27.708′W) has emerged from under more than 297–465 m of glacial ice during the last few thousand years. This paper presents data from a multidisciplinary investigation of the palaeolimnology of this lake through a study of a 3.8 m sediment core extracted at a depth of 93.4 m below the ice surface. The core was dated using a combination of radiocarbon, optically stimulated luminescence, and relative palaeomagnetic intensity dating incorporated into a chronological model. Stratigraphic analyses included magnetic susceptibility, clast provenance, organic content, carbonate composition, siliceous microfossils, isotope and biogeochemical markers. Based on the chronological model we provisionally assign a well-defined magnetic polarity reversal event at ca 165 cm in the lake sediments to the Mono Lake excursion (ca 30–34 ka), whilst OSL measurements suggest that material incorporated into the basal sediments might date to 93 ± 9 ka. Four stratigraphic zones (A–D) were identified in the sedimentological data. The chronological model suggests that zones A–C were deposited between Marine Isotope Stages 5–2 and zone A during Stage 1, the Holocene. The palaeolimnological record tracks changes in the subglacial depositional environment linked principally to changing glacier dynamics and mass transport and indirectly to climate change. The sediment composition in zones A–C consists of fine-grained sediments together with sands, gravels and small clasts. There is no evidence of overriding glaciers being in contact with the bed reworking the stratigraphy or removing this sediment. This suggests that the lake existed in a subglacial cavity beneath overriding LGM ice. In zone D there is a transition to finer grained sediments characteristic of lower energy delivery coupled with a minor increase in the organic content attributed either to increases in allochthonous organic material being delivered from the deglaciating catchment, a minor increase in within-lake production or to an analytical artefact associated with an increase in the clay fraction. Evidence of biological activity is sparse. Total organic carbon varies from 0.2 to 0.6%, and cannot be unequivocally linked to in situ biological activity as comparisons of δ13C and C/N values with local reference data suggest that much of it is derived from the incorporation of carbon in catchment soils and gravels and possibly old CO2 in meteoric ice. We use the data from this study to provide guidelines for the study of deep continental subglacial lakes including establishing sediment geochronologies, determining the extent to which subglacial sediments might provide a record of glaciological and environmental change and a brief review of methods to use in the search for life.
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- 2009
11. Exploring former subglacial Hodgson Lake, Antarctica Paper I: site description, geomorphology and limnology
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Dominic A. Hodgson, James Smith, Andy Hodson, Elie Verleyen, Joanne S. Johnson, Stephen Roberts, Michael J. Bentley, Melanie J. Leng, Andreas Cziferszky, David C.W. Sanderson, Adrian J. Fox, and Wim Vyverman
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Archeology ,Global and Planetary Change ,geography ,geography.geographical_feature_category ,Ice stream ,Antarctic ice sheet ,Geology ,Ice shelf ,Oceanography ,Ice core ,Shelf ice ,Sea ice ,Subglacial lake ,Ice sheet ,Geomorphology ,Ecology, Evolution, Behavior and Systematics - Abstract
At retreating margins of the Antarctic Ice Sheet, there are a number of locations where former subglacial lakes are emerging from under the ice but remain perennially ice-covered. This paper presents a site description of one of these lakes, Hodgson Lake, situated on southern Alexander Island, west of the Antarctic Peninsula (72° 00.549′ S, 68° 27.708′ W). First, we describe the physical setting of the lake using topographic and geomorphological maps. Second, we determine local ice sheet deglaciation history and the emergence of the lake using cosmogenic isotope dating of glacial erratics cross-referenced to optically stimulated luminescence dating of raised lake shoreline deltas formed during ice recession. Third we describe the physical and chemical limnology including the biological and biogeochemical evidence for life. Results show that the ice mass over Hodgson Lake was at least 295 m thick at 13.5 ka and has progressively thinned through the Holocene with the lake ice cover reaching an altitude of c. 6.5 m above the present lake ice sometime after 4.6 ka. Thick perennial ice cover persists over the lake today and the waters have remained isolated from the atmosphere with a chemical composition consistent with subglacial melting of catchment ice. The lake is ultra-oligotrophic with nutrient concentrations within the ranges of those found in the accreted lake ice of subglacial Lake Vostok. Total organic carbon and dissolved organic carbon are present, but at lower concentrations than typically recorded in continental rain. No organisms and no pigments associated with photosynthetic or bacterial activity were detected in the water column using light microscopy and high performance liquid chromatography. Increases in SO4 and cation concentrations at depth and declines in O2 provide some evidence for sulphide oxidation and very minor bacterial demand upon O2 that result in small, perhaps undetectable changes in the carbon biogeochemistry. However, in general the chemical markers of life are inconclusive and abiotic processes such as the diffusion of pore waters into the lake from its benthic sediments are far more likely to be responsible for the increased concentrations of ions at depth. The next phases of this research will be to carry out a palaeolimnological study of the lake sediments to see what they can reveal about the history of the lake in its subglacial state, and a detailed molecular analysis of the lake water and benthos to determine what forms of life are present. Combined, these studies will test some of the methodologies that will be used to explore deep continental subglacial lakes.
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- 2009
12. Arctic Paleoclimate Synthesis Thematic Papers
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Joan J. Fitzpatrick, Julie Brigham-Grette, Richard B. Alley, Gifford H. Miller, Leonid Polyak, and James W. C. White
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Archeology ,Global and Planetary Change ,Thematic map ,Arctic ,Paleoclimatology ,Geology ,Physical geography ,Ecology, Evolution, Behavior and Systematics - Published
- 2010
13. Comments on the paper of Yokoyama et al. (2000), entitled 'Timing of the Last Glacial Maximum from observed sea level minima'
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W. R. Peltier
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Archeology ,Global and Planetary Change ,Paleontology ,Northern australia ,Significant difference ,Quaternary science ,Geology ,Last Glacial Maximum ,Ecology, Evolution, Behavior and Systematics ,Sea level ,Holocene - Abstract
In their analysis of relative sea level observations from the J. Bonaparte Gulf of Northern Australia, the authors interpret the raw observations of the Last Glacial Maximum (LGM) lowstand of the sea by invoking the notion that there is a significant difference between the “spatially averaged change in sea level at any time” and what is referred to as ice-equivalent eustatic sea level in Peltier (On eustatic sea level history, Last Glacial Maximum to Holocene, Quaternary Science Review 21 (2002), in press; companion paper). This notion is incorrect as it violates the principle of mass conservation. The implications of this error of interpretation to the primary conclusion of the Yokoyama et al. (Nature 406 (2000) 713–716) analysis, that “the ice-volume equivalent sea level at LGM lies between −135 and −130 m” is discussed herein. It is concluded on the basis of this discussion that, although the argument presented in this paper for such a deep LGM depression of sea level relies upon this invalid notion, it may nevertheless be true that the LGM low stand was greater than the 120 m conventionally assumed.
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- 2002
14. Biostratigraphy, paleomagnetism and geology of the Orce ravine (Southern Spain). Comment on the paper by Gibert et al. (2006)
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J. Agustí, Josep María Parés, and Oriol Oms
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Archeology ,Global and Planetary Change ,geography ,Paleomagnetism ,geography.geographical_feature_category ,Geology ,Biostratigraphy ,Ravine ,Geomorphology ,Archaeology ,Ecology, Evolution, Behavior and Systematics - Published
- 2007
15. New data for the Last Glacial Maximum in Great Britain and Ireland: a Scottish perspective on the paper by Bowen et al. (2002)
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J.D. Peacock, Adrian M. Hall, and E.R. Connell
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Shetland ,Archeology ,Global and Planetary Change ,geography ,geography.geographical_feature_category ,Geology ,Last Glacial Maximum ,Dynamic feature ,Archaeology ,language.human_language ,law.invention ,Irish ,law ,language ,Radiocarbon dating ,Glacial period ,Ice sheet ,North sea ,Ecology, Evolution, Behavior and Systematics - Abstract
The recent reconstruction by Bowen et al. (2002) of the history of the last British and Irish Ice sheet (BIIS) at the Last Glacial Maximum (LGM) resumes a debate over the extent and behaviour of the last Scottish Ice Sheet (ScIS) that extends back over 20 years (Sutherland, 1984). The ScIS at the LGM is seen as restricted in extent, with ice-free peripheral areas that include Buchan, Caithness, Orkney, Shetland, together with extensive areas of the North Sea and the Hebridean and Shetland shelves (Fig. 1). Moreover, the BIIS is viewed as a long-lived, if dynamic feature throughout Oxygen Isotope Stages 4-2. We consider it unfortunate that Bowen et al. (2002) do not refer to much long-standing and recent work in Scotland that indicates extensive glaciation at the LGM yet a ScIS of very limited extent around 30 ka BP. This note seeks to redress that balance. ‘Uncorrected’ radiocarbon ages rather than calibrated ages are referred to below, because calibration before 17 cal ka BP is uncertain (van der Plicht, 2002). A reservoir age of ca. 400 years has been applied to marine C ages, though we recognise that this may be in error prior to ca. 12.5 ka BP (cf. Voelker et al., 1998).
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- 2003
16. Biostratigraphy, paleomagnetism and geology of the Orce ravine (Southern Spain). Comment on the paper by Gibert et al. (2006)
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Agustí, J., Oms, O., and Parés, J.M.
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- 2007
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17. Beringia and beyond: Papers celebrating the scientific career of Andrei Vladimirovich Sher, 1939–2008
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Elias, Scott, primary, Kuzmina, Svetlana, additional, Edwards, Mary E., additional, and Lister, Adrian M., additional
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- 2011
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18. Arctic Paleoclimate Synthesis Thematic Papers
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Fitzpatrick, Joan J., primary, Alley, Richard B., additional, Brigham-Grette, Julie, additional, Miller, Gifford H., additional, Polyak, Leonid, additional, and White, James W.C., additional
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- 2010
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19. Beringia and beyond: Papers celebrating the scientific career of Andrei Vladimirovich Sher, 1939–2008
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Scott A. Elias, Svetlana Kuzmina, Mary E. Edwards, and Adrian M. Lister
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Archeology ,Global and Planetary Change ,History ,Anthropology ,Scientific career ,Geology ,Archaeology ,Ecology, Evolution, Behavior and Systematics ,Beringia - Published
- 2011
20. New data for the Last Glacial Maximum in Great Britain and Ireland: a Scottish perspective on the paper by Bowen et al. (2002)
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Hall, A.M., Peacock, J.D., and Connell, E.R.
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- 2003
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21. Response to: “New data for the Last Glacial Maximum in Great Britain and Ireland: a Scottish perspective on the paper by Bowen et al. (2002) by A.M. Hall, J.D. Peacock, E.R. Connell
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Bowen, D.Q., primary and McCabe, A.M., additional
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- 2003
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22. Comments on the paper of Yokoyama et al. (2000), entitled “Timing of the Last Glacial Maximum from observed sea level minima”
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Peltier, W.R.
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- 2002
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23. Response to: 'New data for the Last Glacial Maximum in Great Britain and Ireland: a Scottish perspective on the paper by Bowen et al. (2002) by A.M. Hall, J.D. Peacock, E.R. Connell
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A.M. McCabe and D.Q. Bowen
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Archeology ,Global and Planetary Change ,Perspective (graphical) ,Geology ,Last Glacial Maximum ,Archaeology ,Ecology, Evolution, Behavior and Systematics - Published
- 2003
24. Reply to comment of Drs U. Radtke and G. Schellmann on the paper by Aguirre, M.L. and Whatley, R.C. (1995). Late quaternary marginal marine deposits and palaeoenvironments from Northeastern Buenos Aires Province, Argentina: A review. Quaternary science reviews, 14, 223–254
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Aguirre, Marina L., primary and Whatley, Robin C., additional
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- 1996
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25. Papers published in radiation measurements volume 23, nos 2/3
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- 1994
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26. Papers published in nuclear tracks and radiation measurements volume 18, nos. 1/2
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- 1992
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27. Reply to comment of Drs U. Radtke and G. Schellmann on the paper by Aguirre, M.L. and Whatley, R.C. (1995). Late quaternary marginal marine deposits and palaeoenvironments from Northeastern Buenos Aires Province, Argentina: A review. Quaternary science reviews, 14, 223–254
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Marina L. Aguirre and Robin C. Whatley
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Archeology ,Global and Planetary Change ,Geography ,Quaternary science ,Geology ,Quaternary ,Archaeology ,Ecology, Evolution, Behavior and Systematics - Published
- 1996
28. Papers published in Nuclear tracks and radiation measurements volume 14, nos. 1/2
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- 1988
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29. Welcome to the forest theatre: Unveiling a Balkan refugium through paleoart.
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Carrión, José, Amorós, Gabriela, Ochando, Juan, Magri, Donatella, Marín-Arroyo, Ana B., Sánchez-Giner, María Victoria, Amorós, Ariadna, Munuera, Manuel, Di Rita, Federico, Michelangeli, Fabrizio, Roksandic, Mirjana, and Mihailović, Dušan
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PALEOLITHIC Period , *MIXED forests , *LANDSCAPES in art , *PALEOECOLOGY , *LAKE sediments - Abstract
This paper presents an artistic paleolandscape experiment based primarily on recent palynological data from the Paleolithic site of Pešturina, in the Central Balkans of Serbia. These data are integrated into the general knowledge of flora and vegetation changes in the Balkans and southern Carpathians obtained through other paleobotanical sequences, especially pollen records from lake sediments. The paleoartistic proposal includes several drawing attempts at different geographic scales with an emphasis on plant taxa and their position within glacial refugia. The contrast with the interglacial situation is also illustrated, but the work especially focuses on the concept of long-term refugia and the altitudinal shifts of steppes, conifers, and broad-leaf trees. An ecological and biogeographical discussion accompanies the illustrations, highlighting the insurmountable methodological limitations and the challenges that pose obstacles to the progress of palynology as a technique for paleoenvironmental reconstruction at the spatial scale. The structure of the paper aims to serve as a guiding example for the teaching and scientific dissemination of paleosciences, from a conservationist perspective that is much needed in the current scenario of global change and biodiversity crisis. • Challenging Traditional Zoocentrism in Paleoartistic Research. • Paleoartistic works show Paleolithic vegetation within a Refugium in Central Balkans. • During the Pleistocene, Balkan Neanderthals survived in the ecotone between steppes and mixed forests. [ABSTRACT FROM AUTHOR]
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- 2024
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30. Exploring Wilton microlithic technologies: New analyses from Rose Cottage Cave, South Africa.
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Guillemard, Iris
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- *
PREHISTORIC tools , *STONE implements , *STONE Age , *CAVES , *ROSES - Abstract
The Later Stone Age of southern Africa sees the succession of varied lithic traditions. The Wilton (8ka BP – second millennium AD) corresponds to the last techno-complex of the LSA in South Africa. It has been typologically recognised over vast geographical areas and seems to last until the progressive disappearance of stone tool industries, while experiencing chronological and geographical variations. While Wilton formal tools, mainly small scrapers and microliths, have received much attention, the ways in which the stone tools themselves were produced are still unknown. This paper provides keys to describe mid-Holocene Wilton microlithic productions at the reference site of Rose Cottage Cave (Free-State). The lithic technological analysis highlights the integrated production of 'ready-made' blanks from one volume, including bladelets. The scraper and backed piece typologies are analysed and reveal an interesting diversity. These results provide a foundation for the building of the technological understanding of the Wilton in southern Africa. This paper ultimately aims to facilitate the exploration of regional and chronological variations at Wilton sites, and, by contrast, to differentiate other lithic traditions in southern Africa. • This paper provides keys for better understanding Wilton lithic technologies in South Africa • The knapping methods allowed for the production of various 'ready-made' blanks from one volume. • Different knapping techniques could have been used within one operational sequence. • The scraper and backed piece typology are more diverse than revealed by previous studies. • The paper provides a base line for future comparative studies. [ABSTRACT FROM AUTHOR]
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- 2024
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31. The changing role of hazelnuts (Corylus avellana) in the Mesolithic diet: The Scheldt basin (W Belgium) as a case-study.
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Crombé, Philippe, Storme, Annelies, Perdaen, Yves, and Vandendriessche, Hans
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- *
HAZEL , *HAZELNUTS , *MESOLITHIC Period , *EDIBLE plants , *DIET , *WATERSHEDS - Abstract
Hazelnuts were an important foodstuff for Early to Mid-Holocene (Mesolithic) hunter-gatherers all over North-western and Central Europe, mainly thanks to their high fat content, the fact that they are easy to collect and process and produce high areal yields. Based on an extensive and well-dated dataset of charred hazelnut shells, collected on Mesolithic camp-sites from the western Scheldt basin (W Belgium), in this paper the availability of this food resource is studied. Unlike other North(west) European regions, the decline in the exploitation and consumption of hazelnuts in the Scheldt basin appears to start early, from the mid-Boreal period onwards. The available high-resolution pollen and anthracological records indicate that this is presumably related to the rapid and substantial expansion of oak, creating a shady environment which was less favourable for hazel. This paper further examines the impact as well as the possible response of Mesolithic hunter-gatherers to this drastic change in subsistence resources, which arose on top of other challenges during the Boreal, such as increased drought and forest fires, abrupt cooling around 9.3 ka and the possible influx of groups from the adjacent drowning North Sea basin. Human responses possibly ranged from increased mobility, over intensified exploitation of other edible plants to increased fish consumption. The paper ends with emphasizing the importance of high-resolution paleoecological studies on a local/regional level as well as the systematic fine-meshed recovery of plant remains, such as charred hazelnut shells, from archaeological sites. • Hazelnuts were an important food resource during the Mesolithic. • Hazelnut consumption in the Scheldt basin dropped drastically in the mid-Boreal. • This is earlier compared to other areas within NW Europe. • Hazel was outcompeted by the rapid expansion of oak. • Hazel decline might have led to a reduced fat intake and associated health problems. [ABSTRACT FROM AUTHOR]
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- 2023
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32. Glacial history of the King Haakon trough system, sub-Antarctic South Georgia.
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Streuff, Katharina Teresa, Lešić, Nina-Marie, Kuhn, Gerhard, Römer, Miriam, Kasten, Sabine, and Bohrmann, Gerhard
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- *
GLACIAL drift , *ANTARCTIC Circumpolar Current , *GLACIAL landforms , *ICE caps , *ICE shelves - Abstract
The glaciated island of South Georgia in the sub-Antarctic is a key area for climate reconstructions, because it is positioned in the Southern Ocean amidst the core belt of the Southern Westerlies and the main fronts of the Antarctic Circumpolar Current. This makes it particularly susceptible to changes in local, regional, but also Southern Hemisphere-wide climate conditions. Marine-geological records recovered from its continental shelf therefore offer unique potential to constrain how ice masses in this part of the Southern Ocean responded to Quaternary climate change, but despite this, little glacial-geomorphological and sedimentological research has been done offshore South Georgia. Here, we present a new suite of glacial landforms, identified from high-resolution bathymetry data, supplemented with acoustic facies from sub-bottom profiles, in order to reconstruct the pre-Holocene glacial history of the King Haakon Trough System on the southwestern South Georgia continental shelf. Our data show numerous landforms common for phases of ice advance and retreat, which are interpreted to document the confluence of two major trunk glaciers during peak glaciation. Progressively elongated linear bedforms imply accelerated ice flow and/or softer sediment substrate towards the shelf edge and suggest that the South Georgia Ice Cap experienced streaming ice and behaved similarly to other palaeo-ice sheets. A grounding-zone wedge close to the shelf edge marks the position of maximum ice extent during a peak glaciation, while clusters of recessional moraines and three large morainal banks indicate repeated phases of staggered retreat. Multiple extensive ice advances are indicated by stacked till sequences within the sub-bottom profiles of the mid- and outer shelf. The second-to-last till generation appears to be slightly more extensive than the most recent glacial till, and could suggest that South Georgia may have had a similar glacial evolution to other sub-Antarctic islands. This paper complements two studies focusing on the Holocene depositional environments and their associated sedimentary processes in the same trough system, in an effort to elucidate an important part of the Quaternary evolution of South Georgia's marine environment. • King Haakon Trough System formed over the course of several glaciations. • Glacial landforms on the modern seafloor show evidence of fast advance and staggered retreat. • Ice stream draining South Georgia Ice Cap during LLGM configured as ice-cliff margin. • Stacked till sequences attest to multiple ice advances to the shelf edge. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. The Late Pleistocene and Holocene chronocultural and anthracological open-air sequence from Mukila (DRC).
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Jungnickel, Katharina V.M., Seidensticker, Dirk, Hubau, Wannes, Mees, Florias, Cornelissen, Els, and Bostoen, Koen
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- *
PLEISTOCENE-Holocene boundary , *HOLOCENE Epoch , *PLEISTOCENE Epoch , *PARTICLE size distribution , *STONE Age - Abstract
Late Pleistocene and Early Holocene open-air archaeological sites have been assumed to be disturbed throughout Central Africa because key sites located on the Kalahari Sand Belt and excavated in the 1970s documented substantial artefact displacement. As a result, only cave sites have long been seen as suitable for presenting reliable vertical chrono-cultural sequences, and minimal effort was made to investigate open-air sites in Central Africa. This paper presents a multi-disciplinary approach combining archaeological, anthracological, and sediment granulometry data to test the vertical integrity of detailed excavations at the open-air site Mukila (DRC). Refitting analysis shows only minor vertical displacement of lithics (6306 artefacts), pottery (1095 sherds) and charcoal (447 fragments), along with a uniform soil particle size distribution throughout the profile. A chronology of 16 radiocarbon dates confirms a continuous age-depth relationship at the site. These data reveal a mostly intact stratigraphy spanning the last 40,000 years. We thus demonstrate that sites along the northern edges of the Kalahari Sand Belt do not per se show vertical disturbance of charcoal and artefact distribution despite uniform grain size distribution. We conclude that a multi-disciplinary approach is mandatory for studying the integrity of archaeological sequences from Central African open-air sites. • The site of Mukila covers 40 millennia and provides a rare glimpse into the lithic production in the Late Pleistocene to the Holocene south of the equatorial rainforest of Central Africa. • The integrity of open-air sites has never been proven by utilising extensive refitting of lithics in combination with anthracological analyses in that region. • We provide a robust protocol for a multi-disciplinary study of site integrity in open-air sites. • The latest Late Stone Age findings are crucial to further our understanding of these insufficiently studied communities. [ABSTRACT FROM AUTHOR]
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- 2024
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34. The deglacial history of 79N glacier and the Northeast Greenland Ice Stream.
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Roberts, David H., Lane, Timothy P., Jones, Richard S., Bentley, Michael J., Darvill, Christopher M., Rodes, Angel, Smith, James A., Jamieson, Stewart S.R., Rea, Brice R., Fabel, Derek, Gheorghiu, Delia, Davidson, Allan, Cofaigh, Colm Ó, Lloyd, Jerry M., Callard, S. Louise, and Humbert, Angelika
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GREENLAND ice , *ICE streams , *ICE shelves , *GLACIERS , *BEDROCK , *ICE sheets - Abstract
The Northeast Greenland Ice Stream (NEGIS) is the main artery for ice discharge from the northeast sector of the Greenland Ice Sheet (GrIS) to the North Atlantic. Understanding the past, present and future stability of the NEGIS with respect to atmospheric and oceanic forcing is of global importance as it drains around 17% of the GrIS and has a sea-level equivalent of 1.6 m. This paper reconstructs the deglacial and Holocene history of Nioghalvfjerdsbræ (or 79N Glacier); a major outlet of the NEGIS. At high elevation (>900 m asl) autochthonous blockfield, a lack of glacially moulded bedrock and pre LGM exposure ages point to a complex exposure/burial history extending back over half a million years. However, post Marine Isotope Stage 12, enhanced glacial erosion led to fjord incision and plateaux abandonment. Between 900 and 600 m asl the terrain is largely unmodified by glacial scour but post LGM erratics indicate the advection of cold-based ice through the fjord. In contrast, below ∼600 m asl Nioghalvfjerdsfjorden exhibits a geomorphological signal indicative of a warm-based ice stream operating during the last glacial cycle. Dated ice marginal landforms and terrain along the fjord walls show initial thinning rates were slow between ∼23 and 10 ka, but post-10 ka it is evident that Nioghalvfjerdsfjorden deglaciated extremely quickly with complete fjord deglaciation below ∼500 m asl between 10.0 and 8.5 ka. Both increasing air and ocean temperatures were pivotal in driving surface lowering and submarine melt during deglaciation, but the final withdrawal of ice through Nioghalvfjerdsfjorden was facilitated by the action of marine ice sheet instability. Our estimates show that thinning and retreat rates reached a maximum of 5.29 ma−1 and 613 ma−1, respectively, as the ice margin withdrew westwards. This would place the Early Holocene disintegration of this outlet of the NEGIS at the upper bounds of contemporary thinning and retreat rates seen both in Greenland and Antarctica. Combined with recent evidence of ice stream shutdown during the Holocene, as well as predictions of changing ice flow dynamics within downstream sections of the NEGIS catchment, this suggests that significant re-organisation of the terminal zone of the ice stream is imminent over the next century. • The Northeast Greenland Ice Stream (NEGIS) thinned slowly between 23–10ka as ice retreated across the continental shelf. • At the opening of the Holocene rising air & ocean temperatures drove surface lowering & basal melt. • Between 10-8.5ka marine ice sheet instability further enhanced grounding line retreat rates into Nioghalvfjerdsfjorden. • During the Early Holocene thinning and retreat rates reached a maximum of 5.29 ma-1 and 613 ma-1 respectively. • Such rates are at the upper bounds of contemporary ice stream thinning and retreat rates in Greenland and Antarctica. [ABSTRACT FROM AUTHOR]
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- 2024
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35. Salt production by ignition during the prehistory in the Iberian Peninsula with special focus on the archaeological site of Espartinas (Ciempozuelos, Spain).
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Jiménez-Espejo, Francisco J., López-Sáez, José Antonio, Bulian, Francesca, Valiente, Santiago, Giles, Francisco, Ayarzagüena Sanz, Mariano, Garrido-Pena, Rafael, Gonzalez-Ramón, Antonio, Carrascal, José María, López Cidad, Fernando, Barril Vicente, Magdalena, and Camuera, Jon
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ARCHAEOLOGICAL excavations , *SODIUM sulfate , *COPPER Age , *SALT , *PENINSULAS , *ARTIFICIAL seawater , *POLYMER networks - Abstract
One of the prehistoric techniques of salt production consisted of using ceramic vessels, known as briquetage, for the artificial evaporation of salt water. This paper summarizes all the archaeological sites throughout the Iberinan Peninsula where briquetage has been described to date, with special focus on the well-studied archaeological site of Espartinas saltworks. At Espartinas we found the use of two different kinds of ceramics, which points to a two-step process also involving halfah or esparto grass, which may well have been used for transport or/and as an insulating layer between the vessels walls and the mass of salt to facilitate the extraction of whole salt cakes. Palaeoenvironmental conditions at Espartinas have also been described based on local and regional pollen records and compared with the dry conditions associated to the so-called "4.2 cal kyr BP abrupt climatic event". Despite the reduced amount of radiocarbon dating, the briquetage appears have been present in the studied region from the Late Neolithic to at least the Bronze Age. However, we cannot discard the fact that it might have reached the early Roman period, when salt evaporation ponds replaced this laborious technique. Moreover, briquetage distribution has been compared with evaporite outcrops throughout the Iberian Peninsula and it has been observed a characteristic pattern with a preference for peripheral, near to coast regions, with the exception of from Aranjuez-Getafe lower-Miocene lacustrine evaporites in central Iberia. Briquetage spread also shows a marked correlation with sites characterized by the presence of Atlantic halberds the first true metal weapon ever made in Western Europe and part of the warrior panoply of Late Copper Age/Early Bronze Age elites. At least during this period, these findings suggest that briquetage was used to obtain solid salt cakes easily transportable to medium and large distances by Atlantic and intra-Iberian trade exchange networks, which confirms previous studies that associate Bell Beaker phenomenon with salt circulation. • A review of evidence of briquetage in the Iberian Peninsula Prehistory is described. • Factors that appear to have affected the distribution of briquetage are described. • During the Late Copper Age/Early Bronze Age a marked correlation between briquetage sites and Atlantic halberds is described. • Salt pans appear to have been highly demanded during environmental conditions associated with the 4.2 cal kyr BP climatic event. [ABSTRACT FROM AUTHOR]
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- 2024
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36. Brine-boiling not using briquetage? Technical, socio-economical and ritual aspects of salt production at the Villafáfila lagoons (central Iberia) in Late Chalcolithic/Bronze Age.
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Guerra-Doce, Elisa, Abarquero Moras, F. Javier, Romero-Brugués, Susagna, Herrero-Otal, Maria, Homs, Anna, García Cuesta, José Luis, López Sáez, José Antonio, Piqué, Raquel, and Delibes de Castro, Germán
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BRONZE Age , *LAGOONS , *SODIUM sulfate , *BRACKISH waters , *ANIMAL sacrifice , *SALT - Abstract
By combining a multidisciplinary approach and an intensive program of scientific techniques, this paper provides a comprehensive overview of salt production at the Villafáfila lagoons (Zamora, Spain) in prehistoric times. During the Late Chalcolithic and the Early/Middle Bronze Age salt was obtained by boiling brine from salt lagoons. In many parts of western and central Europe at the time the standard procedure for forcing evaporation usually involved the use of crudely fired clay vessels (briquetage) to concentrate brine, and then to mould salt. We suggest that the methods during the final stages of the process differed at Villafáfila, having found evidence of basketry and textiles, which may have been used in the step of crystallization/transport of salt in cake, instead of the small ceramic salt moulds which would be expected in such sites. The role of salt within the socioeconomic setting of the 3rd and 2nd millennia BCE in Central Iberia is also assessed. It is argued that the production and distribution of salt contributed significantly to the political economy, as elites controlled this activity, supporting the idea that salt was a prestige good that contributed to the accumulation of wealth. There is also evidence of ritual practices in the salt-processing areas, as human burials and animal sacrifices have been documented in the excavated sites. • Archaeological evidence shows the production of salt at the Villafáfila lagoons by the late 3rd millennium BCE, during the Beaker period. • Brackish water was boiled in large ceramic vessels supported by clay or stone pedestals. • Techniques evolved during the Early Bronze Age, when pedestals were replaced by clay-walled kilns. • Absence of genuine briquetage, and of small ceramic pots used as salt moulds. • Possible use of baskets and textiles sacks as moulds. [ABSTRACT FROM AUTHOR]
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- 2024
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37. Pleistocene shifts in Great Basin hydroclimate seasonality govern the formation of lithium-rich paleolake deposits.
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Bhattacharya, Tripti, Brennan, Peter R., Ibarra, Daniel E., Gagnon, Catherine A., Butler, Kristina L., Terrazas, Alexa, Miller, Shaw, Munk, Lee Ann, Boutt, David F., Feng, Ran, Bullinger, Stephanie N., and Weisbeck, Lucy
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OCEAN temperature , *PLIOCENE-Pleistocene boundary , *HYDROGEN isotopes , *PLEISTOCENE Epoch , *CARBON isotopes , *RAINFALL , *WINTER storms - Abstract
Southwestern North America is currently experiencing a multidecadal megadrought, with severe consequences for water resources. However, significant uncertainty remains about 21st century precipitation changes in this semi-arid region. Paleoclimatic records are essential for both contextualizing current change, and for helping constrain the sensitivity of regional hydroclimate to large-scale global climate. In this paper, we present a new 2.8 Ma to present compound-specific isotopic record from Clayton Valley, the site of a long-lived paleolake in the southern Great Basin. Hydrogen and carbon isotopes from terrestrial plant leaf waxes provide evidence of past shifts in rainfall seasonality as well as ecosystem structure, and help contextualize the formation of this lithium-rich lacustrine basin. Our results suggest that regional hydroclimates underwent a substantial reorganization at the Plio-Pleistocene boundary, especially between 2.6 and 2.0 Ma. In this interval, a reduced latitudinal temperature gradient in the North Pacific likely resulted in a northward shift in storm tracks, and a reduction in winter rainfall over the southern Great Basin. This occurred against a background of increased summer rainfall and a greater accumulation of lithium in the lake basin. Our interpretation is corroborated by a compilation of Plio-Pleistocene north Pacific sea surface temperature records, as well as an isotope-enabled model simulation. Overall, these results suggest that past shifts in rainfall seasonality helped set the stage for the development and dessication of lithium-rich lacustrine deposits. • We present a new record from Clayton Valley, Nevada in the southern Great Basin. • Leaf wax hydrogen isotopes reveal long-term changes in rainfall seasonality. • Reduced winter rainfall between 2.6 and 2.0 Ma driven by ocean temperature changes. • Hydroclimate changes critical to formation of lithium-rich lacustrine deposits. [ABSTRACT FROM AUTHOR]
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- 2024
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38. New evidence reveals the earliest use of cinnabar in the western Mediterranean: The Neolithic settlement of La Marmotta (Lazio, Italy).
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Petrinelli Pannocchia, Cristiana, Vassanelli, Alice, Palleschi, Vincenzo, Legnaioli, Stefano, Mineo, Mario, Zamora, Gerard Remolins, Mazzucco, Niccolò, and Gibaja, Juan F.
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CINNABAR , *NEOLITHIC Period , *RESEARCH personnel , *HUMAN evolution - Abstract
Numerous researchers point out the emergence of human symbolism is related to the evolution of the complexity of human cognition. Red mineral pigments have been used extensively, particularly with anatomically modern humans, for various purposes. However, the management and supply of these pigments during prehistoric periods remains poorly investigated. Still today, the limited application of physico-chemical analyses often leads to a simplistic attribution of these pigments as ochre. The studies of data from recent literature presented in our paper show a progressive introduction and exploitation of cinnabar ore, to achieve a red pigment, from the seventh millennium BC. In this panorama, the new data obtained from the analyses of samples of artefacts from La Marmotta (Italy) show a wide use of cinnabar in central Italy from the early Neolithic and attest to the earliest use of this ore in the western Mediterranean area. • Pigments can provide insight into changes in the traditions and symbolic practices of human groups during prehistoric times. • XRF and Raman analyses are used to determine pigment composition. • Residues on personal ornaments at La Marmotta (Italy) attest to the first use of cinnabar in the Western Mediterranean. • The chrono-cultural diffusion of cinnabar in the Mediterranean basin follow the arrhythmic wave of the Neolithisation. [ABSTRACT FROM AUTHOR]
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- 2024
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39. The oldest fossil hominin from Italy: Reassessment of the femoral diaphysis from Venosa-Notarchirico in its Acheulean context.
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Micarelli, Ileana, Minozzi, Simona, Rodriguez, Laura, di Vincenzo, Fabio, García-González, Rebeca, Giuffra, Valentina, Paine, Robert R., Carretero, José-Miguel, Fornaciari, Gino, Moncel, Marie-Hélène, and Manzi, Giorgio
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FOSSIL hominids , *NEANDERTHALS , *ARGON-argon dating , *FOSSILS , *PALEOLITHIC Period - Abstract
Venosa-Notarchirico is a musealized Lower Paleolithic site in southern Italy (Basilicata), where a human femoral shaft was discovered in 1985. The fossil specimen can be evaluated in the new light of excavations started in 2016, which provide a more updated and extensive picture of the site, including the crucial Ar/Ar date of 661-614 ka for the human specimen. This makes the fossil diaphysis from Venosa-Notarchirico (Vn-H1) the oldest fossil hominin found so far in the Italian peninsula, associated with the earliest evidence of genuine Acheulean in Europe. In this paper, we report a comparative morphometric analysis of this femur, as well as a paleopathological reappraisal of the periosteal alteration that affects the specimen, supported by an unpublished histological analysis. Vn-H1 represents the proximal two-thirds of a right femur lacking the epiphyseal region. We argue it belonged to an immature individual, possibly a juvenile (late adolescent). Its features suggest that the specimen may refer to an archaic (i.e. , non-modern) human species, also showing morphological differences compared to fossil samples of the Neanderthal lineage. We also support the identification of a pathological condition affecting Vn-H1, particularly evident in some preserved portions of the mid-shaft as described here. Its etiology is discussed after differential diagnosis, which led us to suggest an alteration of inflammatory origin, viewed as a nonspecific periosteal response. This pathology may have been roughly concomitant with the death of the individual. • Vn-H1 represents the oldest human fossil specimen ever found in Italy within one of the earliest Acheulean sites in Europe. • The age of Vn-H1, dated Ar/Ar at 661-614 ka, takes advantage of the recent new excavations at the Venosa-Notarchirico site. • Both morphology and morphometry of the human specimen suggest an age at death of the individual to the late adolescence. • Palaeopathological observations, supported by unpublished histological data, suggest the nature of the periosteal alteration. [ABSTRACT FROM AUTHOR]
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- 2024
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40. Length of astronomical seasons, total and average insolation over seasons.
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Berger, André, Yin, Qiuzhen, and Wu, Zhipeng
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SOLAR radiation , *EARTH'S orbit , *SEASONS , *CLIMATE change , *MILANKOVITCH cycles , *HOLOCENE Epoch , *LATITUDE - Abstract
Daily insolation at a given latitude is often used in the explanation of the long-term variations of paleoclimate records. However, the length of astronomical seasons, which has been paid less attention, could also be important. This paper provides an original calculation of the length of these seasons using the eccentric anomaly. The past and future long-term variations as well as the spectral characteristics of the length of astronomical seasons, of the total and average insolation over the astronomical seasons and of the caloric insolation are shown and compared. The length of astronomical seasons is only a function of climatic precession. The total irradiation for a given latitude and an astronomical season is mainly a function of obliquity except that it is mainly a function of eccentricity in a latitudinal band that is season dependent and from where the phase between obliquity and total irradiation reverses (e.g. ∼11.5°N for the astronomical northern hemisphere summer half-year). The spectral characteristic of the mean insolation over the astronomical summer half-year varies in latitude and time. It contains stronger obliquity signal in high latitudes than in low latitudes, but the obliquity signal already gets very weak at 45°N/S leaving the dominance of climatic precession between 45°N and 45°S. The variation of the mean summer half-year insolation over the last 1 Ma is characterized by a Mid-Brunhes transition at ∼450 ka BP, with a dominant role of climatic precession at all latitudes before ∼450 ka BP but significantly enhanced role of obliquity in high latitudes after this time. The simultaneous weakening of the variations of climatic precession and obliquity around 800 ka ago, a time corresponding to the Mid-Pleistocene Transition, leads to weak variations in both total and mean seasonal insolation. The insolation of a specific case, the Holocene, is finally discussed. Depending on the sensitivity to different types of insolation, different climate variables and regions could show different evolution and trend during the Holocene. • An original calculation of the length of the astronomical seasons is provided. • Precession and obliquity contribute differently to the length of astronomical seasons and to different insolation metrics. • Distinctive variations of total and mean seasonal insolation characterize the Mid-Brunhes and Mid-Pleistocene transitions. • Different insolation metrics display different trend over the Holocene. [ABSTRACT FROM AUTHOR]
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- 2024
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41. A blended model of mobility behavior: Clovis period hunter-gatherers at the Gault Site.
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Speer, Charles A.
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HUMAN behavior models , *HUNTER-gatherer societies , *PLANT diversity , *ANIMAL diversity , *LASER ablation - Abstract
This paper reviews previous work conducted on Laser Ablation – Inductively Coupled Plasma – Mass Spectrometry (LA-ICP-MS) sourcing 33 Clovis period projectile points from the Gault Site (41BL323) in Central Texas. This paper includes new geochemical data from four new primary geologic sources to increase an Edwards Plateau region chert database to 302 primary geologic samples from 204 samples with which to test against the geochemistry of the 33 Clovis artifacts. These artifacts are then assessed with regards to their form, breakage patterns, and distance to source to suggest a blended model of mobility for Clovis period hunter-gatherers in Central Texas. This data suggests that the pattern of movement across the landscape of the Edwards Plateau for these hunter-gatherers may have been a blended pattern alternating between collector and forager based on changing distribution of resources seasonally. This patterning may have been influenced for the Gault Clovis hunter-gatherers reliant on availability of chert resources as well as ecotonal density and diversity of plants and animals; especially, as gauged by Clovis site types and distribution spread throughout much of the Southern Great Plains. • Clovis hunter-gatherers at the Gault Site used chert from over 300 km away. • Breakage and discard patterns of non-local and local chert suggests long distance mobility. • Gault Clovis hunter-gatherer likely alternated their mobility strategies throughout the year. [ABSTRACT FROM AUTHOR]
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- 2019
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42. Subglacial permafrost evidencing re-advance of the Greenland Ice Sheet over frozen ground.
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Ruskeeniemi, Timo, Engström, Jon, Lehtimäki, Jukka, Vanhala, Heikki, Korhonen, Kimmo, Kontula, Anne, Claesson Liljedahl, Lillemor, Näslund, Jens-Ove, and Pettersson, Rickard
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PERMAFROST , *SUBGLACIAL lakes , *GREENLAND ice , *FROZEN ground , *BOREHOLES , *ATMOSPHERIC temperature - Abstract
Abstract Greenland Ice Sheet (GrIS) covers an area of 1.7 million km2. It has been an important source of climate information and the air temperature history of Greenland is well known. However, the thermal history and temperature conditions of the Greenland bedrock are poorly known. There are only few records on the temperature of the proglacial bedrock and no records on bedrock temperature underneath the ice sheet. The Greenland Analogue Project (GAP) recently investigated hydrological, hydrogeological and geochemical processes in Kangerlussuaq, West Greenland. Because permafrost has a major hydrological impact in Arctic regions, the cryogenic structure of the bedrock was an important research topic. From previous studies it was already known that Kangerlussuaq is located within the zone of continuous permafrost. Temperature profiling in a new research borehole, extending horizontally 30 m underneath the ice sheet, revealed that permafrost is 350 m deep at the ice margin. This result raised the question how far the permafrost extends under the ice sheet? In order to investigate the thermal properties, we made a series of electromagnetic (EM) soundings at the ice margin area – on proglacial area and on the ice sheet – and detected, that subglacial permafrost extends at least 2 km from the ice margin to inland. We also observed a patchy unfrozen sediment layer between the ice and the frozen bedrock. Possible existence of subglacial sediments and their role in ice dynamics has been debated in many recent papers. Our successful campaign shows that geophysics can be used for bedrock investigations through thick ice, which is known to be challenging for electromagnetic methods. Our results provide the first direct evidence supporting the proposed Holocene ice re-advance over frozen ground, and contribute to the discussion on the rapid climate changes in past, to the future of the ice sheet under warming climate and hydrogeology at the ice margin. Highlights • This paper is related to an international research project, the Greenland Analogue Project. • Electromagnetic method was able to discriminate unfrozen and frozen ground. • The first published description of cryogenic structure under continental ice sheet. • Ice re-advance over permafrost evidencing significant Holocene retreat to the east. • A literature review of the Holocene deglaciation of West Greenland. [ABSTRACT FROM AUTHOR]
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- 2018
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43. Ice marginal dynamics of the last British-Irish Ice Sheet in the southern North Sea: Ice limits, timing and the influence of the Dogger Bank.
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Roberts, David H., Evans, David J.A., Callard, S. Louise, Clark, Chris D., Bateman, Mark D., Medialdea, Alicia, Dove, Dayton, Cotterill, Carol J., Saher, Margot, Cofaigh, Colm Ó, Chiverrell, Richard C., Moreton, Steven G., Fabel, Derek, and Bradwell, Tom
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ICE sheets , *GLACIAL landforms , *OPTICALLY stimulated luminescence dating , *GEOMORPHOLOGY , *SUBMARINE topography , *BANKS (Oceanography) , *MARINE sediments - Abstract
The southern North Sea is a particularly important area for understanding the behaviour of the British-Irish Ice Sheet (BIIS) during the last glacial cycle. It preserves a record of the maximum extent of the eastern sector of the BIIS as well as evidence for multiple different ice flow phases and the dynamic re-organisation of the BIIS. However, to date, the known ice sheet history and geochronology of this region is predominantly derived from onshore geological evidence, and the offshore imprint and dynamic history of the last ice sheet remain largely unknown. Using new data collected by the BRITICE-CHRONO project this paper explores the origin and age of the Dogger Bank; re-assesses the extent and age of the glaciogenic deposits across the shallow areas of the North Sea between the Dogger Bank and the north Norfolk coast and; re-examines the dynamic behaviour of the BIIS in the southern North Sea between 31.6 and 21.5 ka. This paper shows the core of the Dogger Bank to be composed glaciolacustrine sediment deposited between 31.6 and 25.8 ka. Following its formation the western end of the Dogger lake was overridden with ice reaching ∼54°N where the ice margin is co-incident with the southerly extent of subglacial tills previously mapped as Bolders Bank Fm. This initial ice override and retreat northwards back across the Dogger lake was complete by 23.1 ka, but resulted in widespread compressive glaciotectonism of the lake sediments and the formation of thrust moraine complexes. Along the northern edge of the bank moraines are on-lapped by later phase glaciolacustrine and marine sediments but do not show evidence of subsequent ice override. The shallow seafloor to the west and southwest of the Dogger Bank records several later phases of ice advance and retreat as the North Sea Lobe flowed between the Dogger Bank and the Yorkshire/Lincolnshire coasts and reached North Norfolk. New optically stimulated luminescence (OSL) ages from Garrett Hill on outwash limit the arrival of the BIIS on the Norfolk coast to 22.8–21.5 ka. Multiple till sheets and chains of moraines on the seafloor north of Norfolk mark dynamic oscillation of the North Sea Lobe margin as it retreated northwards. This pattern of behaviour is broadly synchronous with the terrestrial record of deposition of subglacial, glaciofluvial and glaciolacustrine sediments along the Yorkshire coast which relate to post Dimlington Stadial ice marginal oscillations after 21.5 ka. With respect to forcing mechanisms it is likely that during the early phases of the last glacial maximum (∼30-23ka) the interaction between the southern margin of the BIIS and the Dogger Lake was critical in influencing flow instability and rapid ice advance and retreat. However, during the latter part of the last glacial maximum (22–21 ka) late-phase ice advance in the southern North Sea became restricted to the western side of the Dogger Bank which was a substantial topographic feature by this time. This topographic confinement, in addition to decoupling of the BIIS and the Fennoscandian Ice Sheet (FIS) further north, enabled ice to reach the north Norfolk coast, overprinting the seabed with late-phase tills of the Bolders Bank Fm. Highlights • New acoustic and chronological data from the southern North Sea casts fresh light on British-Irish Ice Sheet history. • The Dogger Bank is composed of glaciolacustrine sediment heavily glaciotectonised between 31.6 and 23.1 ka. • A key trigger for the re-advance of the British-Irish Ice Sheet at 21.5 ka was the catastrophic drainage of Dogger Lake. [ABSTRACT FROM AUTHOR]
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- 2018
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44. The stable isotope composition of organic and inorganic fossils in lake sediment records: Current understanding, challenges, and future directions.
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van Hardenbroek, M., Chakraborty, A., Davies, K.L., Harding, P., Heiri, O., Henderson, A.C.G., Holmes, J.A., Lasher, G.E., Leng, M.J., Panizzo, V.N., Roberts, L., Schilder, J., Trueman, C.N., and Wooller, M.J.
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STABLE isotope analysis , *AQUATIC organisms , *LAKE sediments , *STABLE isotopes , *PALEOENVIRONMENTAL studies - Abstract
Abstract This paper provides an overview of stable isotope analysis (H, C, N, O, Si) of the macro- and microscopic remains from aquatic organisms found in lake sediment records and their application in (palaeo)environmental science. Aquatic organisms, including diatoms, macrophytes, invertebrates, and fish, can produce sufficiently robust remains that preserve well as fossils and can be identified in lake sediment records. Stable isotope analyses of these remains can then provide valuable insights into habitat-specific biogeochemistry, feeding ecology, but also on climatic and hydrological changes in and around lakes. Since these analyses focus on the remains of known and identified organisms, they can provide more specific and detailed information on past ecosystem, food web and environmental changes affecting different compartments of lake ecosystems than analyses on bulk sedimentary organic matter or carbonate samples. We review applications of these types of analyses in palaeoclimatology, palaeohydrology, and palaeoecology. Interpretation of the environmental ‘signal’ provided by taxon-specific stable isotope analysis requires a thorough understanding of the ecology and phenology of the organism groups involved. Growth, metabolism, diet, feeding strategy, migration, taphonomy and several other processes can lead to isotope fractionation or otherwise influence the stable isotope signatures of the remains from aquatic organisms. This paper includes a review of the (modern) calibration, culturing and modelling studies used to quantify the extent to which these factors influence stable isotope values and provides an outlook for future research and methodological developments for the different examined fossil groups. Highlights • Review of stable isotopes in the remains of aquatic organisms in lake sediments. • Stable O and Si isotopes in biogenic silica (diatoms). • Stable C and O isotopes in biogenic carbonates (ostracods, molluscs, charophytes). • Stable H, C, N and O isotopes in aquatic plant, invertebrate, and fish remains. • Outlook on controlled experiments, calibrations, taphonomic studies, and modelling. [ABSTRACT FROM AUTHOR]
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- 2018
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45. The Island of Amsterdamøya: A key site for studying past climate in the Arctic Archipelago of Svalbard.
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Bakke, Jostein, Balascio, Nicholas, van der Bilt, Willem G.M., Bradley, Raymond, D' Andrea, William J., Gjerde, Marthe, Ólafsdóttir, Sædís, Røthe, Torgeir, and De Wet, Greg
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LAKE sediments , *PALEOCLIMATOLOGY , *HYDROGEN isotopes , *PALEOTHERMOMETRY - Abstract
This paper introduces a series of articles assembled in a special issue that explore Holocene climate evolution, as recorded in lakes on the Island of Amsterdamøya on the westernmost fringe of the Arctic Svalbard archipelago. Due to its location near the interface of oceanic and atmospheric systems sourced from Arctic and Atlantic regions, Amsterdamøya is a key site for recording the terrestrial response to marine and atmospheric changes. We employed multi-proxy approaches on lake sediments, integrating physical, biogeochemical, and isotopic analyses to infer past changes in temperature, precipitation, and glacier activity. The results comprise a series of quantitative Holocene-length paleoclimate reconstructions that reveal different aspects of past climate change. Each of the four papers addresses various facets of the Holocene climate history of north-western Svalbard, including a reconstruction of the Annabreen glacier based on the sedimentology of the distal glacier-fed lake Gjøavatnet, a reconstruction of changing hydrologic conditions based on sedimentology and stratigraphy in Lake Hakluytvatnet, reconstruction of summer temperature based on alkenone paleothermometry from lakes Hakluytvatnet and Hajeren, and a hydrogen isotope-based hydrological reconstruction from lake Hakluytvatnet. We also present high-resolution paleomagnetic secular variation data from the same lake, which document important regional magnetic field variations and demonstrate the potential for use in synchronizing Holocene sedimentary records in the Arctic. The paleoclimate picture that emerges is one of early Holocene warmth from ca. 10.5 ka BP interrupted by transient cooling ca. 10-8ka BP, and followed by cooling that mostly manifested as two stepwise events ca. 7 and 4 ka BP. The past 4ka were characterized by dynamic glaciers and summer temperature fluctuations decoupled from the declining summer insolation. [ABSTRACT FROM AUTHOR]
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- 2018
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46. Speleothem records from western Thailand indicate an early rapid shift of the Indian summer monsoon during the Younger Dryas termination.
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Jacobson, Matthew J., Chawchai, Sakonvan, Scholz, Denis, Riechelmann, Dana F.C., Holmgren, Karin, Vonhof, Hubert, Wang, Xianfeng, and Liu, Guangxin
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YOUNGER Dryas , *SPELEOTHEMS , *MONSOONS , *STALACTITES & stalagmites , *STABLE isotopes , *SUMMER , *COMPLEX variables - Abstract
Mainland Southeast Asia experiences complex and variable hydroclimatic conditions, mainly due to its location at the intersection of Asian monsoon subsystems. Predicting future changes requires an in-depth understanding of paleoclimatic conditions that is currently hindered by a paucity of records in some regions. In this paper, we present the first speleothem stable isotope records from western Thailand detailing the Bølling-Allerød interstadial, Younger Dryas termination, and early- to mid-Holocene period. We find evidence of higher precipitation during the Bølling-Allerød (14,321–12,824 years before present (1950: BP)) compared to a Younger Dryas termination that starts 11,702–11,674 BP, has a rapid shift centered on 11,660–11,641 BP, and ends 11,603–11,589 BP. In addition, our records show Holocene monsoon intensity peaking at 8250 BP or before, a multi-millennia delay from the Northern Hemisphere summer insolation peak, followed by a trend to drier conditions until at least 750 BP. Assessment of the timing of the Younger Dryas termination in paleoclimate records across Southeast Asia reveals an earlier shift of the Indian Summer Monsoon to global climate shifts when compared to East Asian Summer Monsoon records. The causes of this are currently unknown. Some potentially important aspects include: an Indian Summer Monsoon influence on East Asian Summer Monsoon strength via the Indian Ocean Dipole climate pattern, the role of the Tibetan Plateau in monsoon dynamics, and exposure of the Sundaland shoreline. More high-resolution paleoclimate records, especially on the pathway of Indian Summer Monsoon to East Asian Summer Monsoon, are required for further discussion on the mechanisms controlling the differences between climate regimes. • We present two new speleothem stable isotope records from western Thailand. • Conditions trend wetter during the Bølling-Allerød. • Early and abrupt termination of the Younger Dryas (11,675–11,600 BP, ±73 years). • Change Point Analysis of records finds earlier rapid shift in Indian Summer Monsoon. • Distinct trend of increasing δ18O and δ13C values throughout Holocene. [ABSTRACT FROM AUTHOR]
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- 2024
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47. Tropical forcing and ENSO dominate Holocene climates in South Africa's southern Cape.
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Chase, Brian M., Boom, Arnoud, Carr, Andrew S., and Reimer, Paula J.
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HOLOCENE Epoch , *SOUTHERN oscillation , *TEMPERATE climate , *RAINFALL ,EL Nino ,AGULHAS Current - Abstract
This paper explores the Holocene climatic dynamics of South Africa's southern Cape, a region that supports a large proportion of the Greater Cape Floristic Region and contains an array of important archaeological sites. While South African climates are generally characterised by marked rainfall seasonality, the southern Cape is currently situated at the interface between tropical and temperate climate systems, resulting in a largely aseasonal rainfall regime. This regime, however, is thought to have been particularly sensitive to past changes in late Quaternary boundary conditions, meaning that variability in either tropical or temperate systems could have significant environmental impacts. Evidence of past climate change, however, remains limited. We present a 9000-year record of hydroclimatic variability obtained from rock hyrax midden stable nitrogen records, from Papkuilsfontein, on the southern slope of the Anysberg Mountains. Resolved to an average 6-year resolution and spanning the period c. 9050 cal yr BP to 1990 CE, this is the highest resolution Holocene record from southern Africa and presents a unique opportunity for the detailed study of the primary drivers and spatial gradients of Holocene climate change in the southern Cape. The data indicate a long-term decrease in aridity across the Holocene and a pattern of variability that reveals remarkable similarities with records from the South African tropics and El Niño–Southern Oscillation proxies, highlighting the significance of tropical systems as drivers of Holocene climate change in the region. This substantially expands what has been previously considered to be the zone of tropical influence, extending from a coastal phenomenon associated with heat transport via the Agulhas Current to encompass much, if not all, of the Agulhas Plain south of the Cape Fold Mountains. These findings provide a valuable new climatic framework for contextualizing changes in ecological and archaeological records in the southern Cape, and contribute to a more comprehensive understanding of the spatio-temporal dynamics of climate systems in southern Africa. • Sub-decadal 9000-year record of aridity from South Africa's southern Cape. • Reveals dominance of tropical forcing across the southern Cape and Agulhas Plain. • ENSO variability indicated to be important driver of regional climate change. • Presents high-resolution framework for study of human-environment interactions. [ABSTRACT FROM AUTHOR]
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- 2024
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48. Not seen before. Unveiling depositional context and Mammuthus meridionalis exploitation at Fuente Nueva 3 (Orce, southern Iberia) through taphonomy and microstratigraphy.
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Yravedra, José, Courtenay, Lloyd A., Gutiérrez-Rodríguez, Mario, Reinoso-Gordo, Juan Francisco, Saarinen, Juha, Égüez, Natalia, Luzón, Carmen, Rodríguez-Alba, Juan José, Solano, José A., Titton, Stefania, Montilla-Jiménez, Eva, Cámara-Donoso, José, Herranz-Rodrigo, Darío, Estaca, Verónica, Serrano-Ramos, Alexia, Amorós, Gabriela, Azanza, Beatriz, Bocherens, Hervé, DeMiguel, Daniel, and Fagoaga, Ana
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MAMMOTHS , *TAPHONOMY , *PROBOSCIDEA (Mammals) , *SEDIMENT analysis , *HOMINIDS , *MEGAFAUNA - Abstract
Meat consumption by early hominins is a hotly debated issue. A key question concerns their access to large mammal carcasses, including megafauna. Currently, the evidence of anthropic cut marks on proboscidean bones older than -or close to- 1.0 Ma are restricted to the archaeological sites of Dmanisi (Georgia), Olduvai (Tanzania), Gona (Ethiopia), Olorgesailie (Kenya) and La Boella (Spain). During an inspection of the almost complete carcass of Mammuthus meridionalis (FN3-5-MPS) from the Oldowan site of Fuente Nueva 3 (Orce, Spain, c. 1.2 Ma), a few traces compatible with human-made cut marks and carnivore tooth marks were found. From this finding and previous interpretations the following questions arise: When and under what conditions was FN3-5-MPS deposited? What is the nature of the marks found on the surface of the bones of this mammoth? To answer, we have conducted a high-resolution analysis of these remains, combining both taphonomic and microstratigraphic data. Our results, using microstratigraphic and micromorphological analyses of sediments based on thin-sections, show that this individual was deposited in a marshy environment. Subsequently, the carcass was exploited by hominins and large felids that left their marks on the surface of some of its bones. For this purpose, the identification and characterisation of both cut marks and tooth marks were performed using high-resolution 3D modelling, geometric morphometrics, and artificially intelligent algorithms. Based on the anatomical position of both the cut and tooth marks, we propose that both the hominins and the saber-toothed cats had early access to the animal. Finally, this paper shows how an interdisciplinary approach can shed detailed light on the particular story regarding the death and processing of the carcass of a female mammoth, deposited at Fuente Nueva 3. • Original contextual approach combining taphonomy and microstratigraphy. • Proboscidean found in FN3 (FN3-5-MPS) died in a watery environment. • Cut and tooth marks reveal proboscidean exploitation by felids and Homo. • Earliest evidence of cut marks on proboscideans bones in western Eurasia. • New insights into the behaviour of the first inhabitants of western Eurasia. [ABSTRACT FROM AUTHOR]
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- 2024
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49. Fecal biomarkers in Italian anthropogenic soil horizons and deposits from Middle Ages and bronze age.
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Bortolini, M., Nicosia, C., Argiriadis, E., Pojana, G., Devos, Y., and Battistel, D.
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SOIL horizons , *ANTHROPOGENIC soils , *BRONZE Age , *FECAL contamination , *MIDDLE Ages , *ANIMAL culture - Abstract
Archaeological excavations in urban and rural contexts often uncover dark homogeneous anthropogenic deposits, soils and soil horizons, known as Dark Earths, Cultural Layers and Anthrosols. Major scientific questions arise about the processes that lead to the formation of these soils and deposits, as they are often related to a complex combination of environmental, climatic, and anthropogenic factors. Many studies focused on the morphological and physical-chemical investigation of the archaeological remains found as well as the inorganic constituent of the soil. The organic fraction has been only roughly investigated and studies carried out on a molecular level are very limited. However, a more refined investigation of the chemical constituents of these soils can potentially reveal pivotal insights on the archaeological context such as past domestic habits and/or urban organization. It has been demonstrated that, among organic matter constituents, fecal steroids are promising biomarkers to track fecal input in many environmental matrixes such as water, soils, and sediments. In this paper we determine the fecal sterols and stanols content in dark homogeneous anthropogenic deposits and soils found in seven archaeological sites in Italy (from Verona, Como, Florence, Mel and Conegliano) dated from the Late Bronze Age and the Medieval Period, aiming to assess the major contribution of the fecal input using diagnostic fecal indexes obtained from specific fecal sterol proportions. To this purpose, a baseline was established by identifying the fecal fingerprint of domestic herbivores (caprids, ovines, equines and bovines) and omnivores (pigs). Based on their fecal fingerprint, we classified the deposits of seven studied sites into four distinct categories: i) the medieval sites of Verona, presented a strong mixed fecal input from both herbivores and humans; ii) the medieval sites of Como and Florence which showed a similar pattern, with a predominance of human fecal input over livestock; iii) the late medieval soils of Mel and the late bronze age Cultural Layers of Castellar di Leppia (Verona) which exhibited a generally scarce fecal contamination while iv) the final bronze age site of Conegliano (Treviso), a strong fecal contamination from herbivores was detected. These results thus demonstrate that for the Medieval Dark Earth the socio-cultural processes leading to the formation of the Dark Earth differ in terms of sewage and waste management and/or in animal husbandry practices. • The molecular fecal fingerprint of domestic animals was established. • Seven archaeological sites in north-central Italy were analyzed for fecal input. • The diverse fecal contamination patterns reveal past habits of sewage and water management. [ABSTRACT FROM AUTHOR]
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- 2024
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50. Speleothems uncover Late Holocene environmental changes across the Nuragic period in Sardinia (Italy): A possible human influence on land use during bronze to post-Iron Age cultural shifts.
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Columbu, Andrea, Pérez-Mejías, Carlos, Regattieri, Eleonora, Lugli, Federico, Dong, Xiyu, Depalmas, Anna, Melis, Rita, Cipriani, Anna, Cheng, Hai, Zanchetta, Giovanni, and De Waele, Jo
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SPELEOTHEMS , *BRONZE Age , *HOLOCENE Epoch , *LAND use , *IRON Age , *ANCIENT civilization - Abstract
During the Bronze and Iron Age, Sardinia was home of one of the most technologically advanced Mediterranean societies (the Nuragic culture). Given its key geographical location, the island was also the fulcrum of deep cultural exchanges. Toward the end of the Iron Age, Phoenicians, and especially Carthaginians and Romans, massively frequented Sardinia for different purposes. This marks an important cultural transition for the region, as the ancient Nuragic-related society terminated. At the same time, this impacted the subsistence and land use practices. Together with middle to late Holocene climate changes, the novel anthropic activities had a pivotal role in shaping the landscape around the island. However, high resolution climate and environmental records for these culturally important phases are still lacking in Sardinia. Thus, this paper explores palaeoenvironmental changes from the Bronze Age to post Iron Ages times by using carbonate speleothems from Suttaterra de Sarpis Cave (Urzulei, central east Sardinia), strategically located nearby the Or Murales Nuragic Village. U–Th ages (n = 20) indicate that five stalagmites comprehensively span the last ∼7000 years. Peculiarly, they all show an evident stratigraphic discontinuity. Age models attest that hiatuses can be at times associated with the discontinuities, spanning periods of ∼1200 to ∼200 years. Importantly, the discontinuities occurred from the Late Iron Age to the Roman period. Based on fabric observations, trace elements and δ13C- δ18O analyses, the discontinuities are primarily attributed to a progressive change of land use above the cave. We suppose that deforestation aimed to clearance for agriculture and livestock practices probably was the most impacting factor for infiltration dynamics and soil state, thus affecting the studied speleothems, although archaeological and historical data are absent for the specific study area. Instead, this is in line with the cultural transition occurring in Sardinia toward the end of the Iron Age, with novel agricultural practices imported by the overseas populations. The anthropic disturbance to the millennial-long karst equilibrium possibly overprinted the response of speleothem proxies to climate oscillations, although future higher resolution analyses are necessary to better investigate the evolution of climate during the Holocene as well as its role in the development of ancient civilizations. Indeed, this is the first speleothem-based Holocene palaeoenvironmental reconstruction accomplished in Sardinia. Considering the paucity of natural lakes in this key location, speleothems here demonstrate their potential in exploring human-driven palaeoenvironmental changes during times of cultural transitions within the Mediterranean context. • The first Holocene speleothem paleoenvironmental record from Sardinia (Italy). • Changes in geochemical and physical speleothems' properties point to variation of land use. • Land use variation is connected to cultural shifts during intra- and post-Nuragic period. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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