Evidence for a humid interval at ∼56-44 ka in the Levant and its potential link to modern humans dispersal out of Africa.

This study provides a detailed reconstruction of the paleoenvironmental conditions that prevailed during one of the periods of modern human migration out of Africa and their occupation of the Eastern Mediterranean-Levant during the Late Middle Paleolithic-Early Upper Paleolithic. Tracing the past vegetation and climate within the Eastern Mediterranean-Levant region is largely based on a south-eastern Mediterranean marine pollen record covering the last 90 kyr (core MD-9509). The various palynomorphs were linked to distinct vegetation zones that were correlated to the two climate systems affecting the study area: the low-latitude monsoon system and the North Atlantic-Mediterranean climate system. The bioprovince palynological markers show that during the period between ∼56 and 44 ka, which covers the early part of Marine Isotope Stage 3 (MIS 3), there was an increase in transportation of pollen from Nilotic origin and a rise in dinoflagellate cyst ratios. These changes coincided with maximum insolation values at 65°N, which led to an enhancement in Nile River discharge into the Eastern Mediterranean following the intensification of the African monsoonal system. At the same time, the rise in Mediterranean arboreal pollen values (broadleaved, coniferous and deciduous temperate trees) is most likely driven by increased precipitation related to the intensification of the North Atlantic-Mediterranean climate system. The ∼56-44 ka wet event coincides with Dansgaard-Oeschger interstadials 14 and 12 and with a warming phase in the Levant, as evidenced by the melting of permafrost along the higher elevations of Mount Hermon. We suggest that African modern humans were able to cross the harsher arid areas due to the intensification of the monsoonal system during the first part of MIS 3, and inhabit the Eastern Mediterranean-Levant region where climatic conditions were favorable (wetter and warmer), even in the currently semiarid/steppe regions.

Dietary reconstruction of the El Sidrón Neandertal familial group (Spain) in the context of other Neandertal and modern hunter-gatherer groups. A molar microwear texture analysis.

Here, we present the analysis of occlusal molar microwear textures of eight individuals from the El Sidrón Neandertal group (Spain). The aims of the study were: 1) to document potential age-, sex-, and maternal lineage-related differences in diet within a Neandertal familial group, and 2) to place the diet of El Sidrón individuals in the context of those of other Neandertal groups. This study also offers an interpretation of the diet of the El Sidrón Neandertals by comparing their microwear signatures to those of recent hunter-gatherer populations with diverse but known diets. The intra-group examination of the microwear signatures are consistent with the females of the El Sidrón group having had more abrasive diets or having used their teeth in more para-masticatory activities than did the males. Aside from the potential sex-related differences in diet, no additional intra-group dietary separation, such as by age group or maternal lineage, was observed. In comparison to other Neandertals, El Sidrón individuals, as a group, have microwear signatures most similar to those of other Neandertals from wooded habitats and different from those that lived in more open habitats. This result is expected based on the available paleoenvironmental reconstructions from El Sidrón Cave. The diet of the El Sidrón Neandertals, just like their Neandertal counterparts from similar wooded habitats, is interpreted as having been mixed, consisting of both meat and vegetable foods.

The Late Neandertal permanent lower left third premolar from Walou Cave (Trooz, Belgium) and its context.

OBJECTIVES: We describe a hominin permanent lower left third premolar unearthed in 1997 at Walou Cave (Belgium), found in direct association with a Mousterian lithic industry, in a layer directly dated to 40-38,000 years BP. MATERIALS AND METHODS: The taxonomical attribution of the tooth is addressed through comparative morphometric analyses, and stable isotope analyses aimed at determining the diet of the individual. RESULTS: The Walou P3 plots within the Neandertal range of variation and is significantly different from recent modern humans in all morphometric assessments. The isotope data showed that like other Neandertals, the Walou individual acquired its dietary proteins primarily from terrestrial food sources. DISCUSSION: We discuss the implications of the existence of a clearly Neandertal premolar dating to the period of the Middle to Upper Paleolithic transition in the Meuse river basin.

Ursus spelaeus (Rosenmüller, 1794) during the MIS 3: new evidence from the Cioclovina Uscata Cave and radiocarbon age overview for the Carpathians.

Ursus spelaeus, the Late Pleistocene a cave bear is known from numerous accumulations found in the fossil sector of caves situated in the Carpathian and Apuseni Mountains. In this study, we present new radiocarbon data along a profile of the Cioclovina Uscata Cave, which is situated in the South Carpathians. The data suggest that, during the entire Marine Isotope Stage 3 (MIS 3) interval, the cave was serving as a shelter for U. spelaeus, with the oldest dated bone indicating an age of > 47,710 and the youngest one, an age of 31,820 ± 400 years cal BP. Histogram plots of 110 radiocarbon data from different caves of the Carpathian and Apuseni Mountains as Cioclovina Uscata, Peștera (Cave) cu Oase, Peștera Muierii, or Peștera Urșilor, respectively, show a maximum expansion of the cave bear population between 50,000 and 40,000, a decline between 40,000 and 35,000 and a partial recovery from 35,000-30,000 years cal BP. Radiocarbon data of Homo sapiens remains, younger than 35,000 years cal BP, support the fact that H. sapiens accessed the same caves where the cave bear persisted to hibernate. Besides general cool conditions and restricted food sources, the presence of H. sapiens constituted an additional stress factor driving the cave bear to extinction.

Widespread glacier advances across the Tian Shan during Marine Isotope Stage 3 not supported by climate-glaciation simulations.

Whether there were more extensive glaciations during the Marine Isotope Stage (MIS) 3 relative to MIS 2 across the Tian Shan in Central Asia is intensely debated because of the uncertainty in chronological data and fully understanding the driving mechanisms. To help resolve the ongoing debate, we assess the climate sensitivity of the glaciers and reconstruct the extent of glaciation during MIS 2 and 3 across the Tian Shan, using a glacier-resolving (250 × 250 m) ice sheet model asynchronously coupled with a global climate model. Our results demonstrate that the equilibrium-line altitude (ELA) over the Tian Shan decreases by ∼180 m for every 1 °C cooling under a modern precipitation regime, but precipitation reduction greatly lowers the sensitivity of the glaciers to temperature decrease (e.g., the effect of 2 °C cooling is broadly offset by a 50% decrease in precipitation). Under the modeled colder/drier-than-present climate, the model predicts an ELA depression (∆ELA) of ∼75 m (162 m) over the Tian Shan during MIS 3 interstadials (stadials). The extent of MIS 3 glaciation is much smaller than that during MIS 2 (i.e., ∆ELA = âˆ¼726 m). The more extensive glaciation during MIS 2 is largely attributed to the enhanced summer cooling. Furthermore, through a site-to-site model-data comparison, we find that the closest match between the modeled glacier margin and the locations of the glacial deposits previously argued to be MIS 3 is generally achieved under MIS 2 climatic conditions. These results suggest more extensive glacier advances over the Tian Shan during MIS 2 than MIS 3 on a regional scale, although MIS 3 glaciation may still occur in individual glacier catchments. This pattern suggests general synchronicity with the timing of maximum Northern Hemisphere ice sheets during the last glacial, which should be further tested in a multimodel framework in the future.

Human occupation continuity in southern Italy towards the end of the Middle Palaeolithic: a palaeoenvironmental perspective from Apulia.

After the last interglacial [Marine Isotope Stage (MIS) 5e] Europe was affected by several harsh climatic oscillations. In this context southern Italy acted, like the rest of peninsular Mediterranean Europe, as a 'glacial refugium', allowing the survival of various species, and was involved in the spread of 'cold taxa' (e.g. woolly mammoth and woolly rhino) only during the coldest phases (MIS 4 and MIS 2). Both late Mousterian and early Upper Palaeolithic sites testify to a human occupation continuity in southern Italy and especially in Apulia in this time span. Here we present a focus on three key Apulian Palaeolithic sequences (Grotta di Santa Croce, Riparo L'Oscurusciuto and Grotta del Cavallo - layers F-E) jointly spanning from the late MIS 4 to the demise of Neanderthals around 43 ka. Novel chronological, sedimentological and zooarchaeological data are discussed for the first time in the light of the palaeoenvironmental information provided by recent analyses carried out on a speleothem from Pozzo Cucù cave (Bari) and the results of the magnetic susceptibility analysis from Riparo L'Oscurusciuto. This integrated reading allows a better understanding of the role played by the Apulian region as both a refugium for late Neaderthals and a suitable habitat for the early settling of modern humans.

High-Resolution Benthic Mg/Ca Temperature Record of the Intermediate Water in the Denmark Strait Across D-O Stadial-Interstadial Cycles.

Dansgaard-Oeschger (D-O) climate instabilities that took place during Marine Isotope Stage 3 are connected to changes in ocean circulation patterns and sea ice cover. Here we explore in detail the configuration of the water column of the Denmark Strait during D-O events 8-5. How the ocean currents and water masses within the Denmark Strait region responded and were connected to the North Atlantic are discussed. We investigate sediment core GS15-198-36CC, from the northern side of the Greenland-Iceland Ridge, at 30-year temporal resolution. Stable carbon and oxygen isotope reconstructions based on benthic foraminifera, together with a high-resolution benthic foraminiferal record of Mg/Ca paleothermometry, is presented. The site was bathed by warm intermediate waters during stadials and cool but gradually warming intermediate water during interstadials. We suggest that stadial conditions in the Denmark Strait are characterized by a well-stratified water column with a warm intermediate water mass that lies beneath a cold fresh body of water where sea ice and brine rejection work in consort to uphold the halocline conditions. Interstadial periods are not a pure replicate of modern times, but rather have two modes of operation, one similar to today, and the other incorporating a brief period of warm intermediate water and increased ventilation.