Expanding Paleoindian Diet Breadth: Paleoethnobotany of Connley Cave 5, Oregon, USA

Paleoethnobotanical perspectives are essential for understanding past lifeways yet continue to be underrepresented in Paleoindian research. We present new archaeobotanical and radiocarbon data from combustion features within stratified cultural components at Connley Caves, Oregon, that reaffirm the inclusion of plants in the diet of Paleoindian groups. Botanical remains from three features in Connley Cave 5 show that people foraged for diverse dryland taxa and a narrow range of wetland plants during the summer and fall months. These data add new taxa to the known Pleistocene food economy and support the idea that groups equipped with Western Stemmed Tradition toolkits had broad, flexible diets. When viewed continentally, this work contributes to a growing body of research indicating that regionally adapted subsistence strategies were in place by at least the Younger Dryas and that some foragers in the Far West may have incorporated a wider range of plants including small seeds, leafy greens, fruits, cacti, and geophytes into their diet earlier than did Paleoindian groups elsewhere in North America. The increasing appearance of diverse and seemingly low-ranked resources in the emerging Paleoindian plant-food economy suggests the need to explore a variety of nutritional variables to explain certain aspects of early foraging behavior.

Numerical Analysis of Aluminium Oxide Nano Particles with Biodiesel in a Diesel Engine Fitted with Hemispherical Groove in the Piston

For proper combustion, bowl in the piston geometry plays a crutial role when the engine valves are in closed position. In the present work, the combustion geometry is of hemi-spherical groove in the upper region of the piston.simulations weres conducted for different blends( b20+al40, b20+al80) to analyze the combustion features in a four stroke diesel engine using ansys r18.1 software considering above geometry of the piston. . Pertaining to greater amount of density, viscosity of biodiesel blends, variations for b20+al80 render more performance than the biodiesel. Turbulent kinetic energy of both the fuels follow similar trend due to proper mixing of air with the fuel from fuel injector.

Magnetic fabric and archaeomagnetic analyses of anthropogenic ash horizons in a cave sediment succession (Crvena Stijena site, Montenegro)

SUMMARY An archaeomagnetic, rock magnetic and magnetic fabric study has been carried out on seven anthropogenic ash horizons in the Middle Palaeolithic sedimentary level XXIV at the rock shelter of Crvena Stijena (‘Red Rock’), Montenegro. The study has multiple goals, including the identification of iron bearing minerals formed during combustion, assessment of the suitability of these combustion features for recording the Earth´s magnetic field direction, revelation of the magnetic fabric and its significance in the characterization of cave (rock shelter) burnt facies, and identification of post-burning alteration processes. Magnetite has been identified as the main ferromagnetic component of the ash. The ash layers exhibit a high thermomagnetic reversibility in contrast to the irreversible behaviour of their subjacent burnt black layers which is related to the different temperatures attained. Seven mean archaeomagnetic directions were obtained with acceptable statistical values indicating that these features recorded the field direction at the time of burning. However, some of them are out of the expected range of secular variation for mid-latitude regions suggesting post-burning alterations. The magnetic fabric of the ash was characterized by anisotropy of low field magnetic susceptibility measurements. Statistical analysis (box and whisker plot) of the basic anisotropy parameters, such as foliation, lineation, degree of anisotropy and the shape parameter, along with the alignment of the principal susceptibilities on stereoplots, revealed variation among the ash units. The diverse, oblate to prolate, lineated or strongly foliated, quasi-horizontally and vertically oriented fabrics of the units may indicate different slope processes, such as orientation by gravity, solifluction, run-off water, quasi-vertical migration of groundwater and post-burning/post-depositional alteration of the fabric by rockfall impact. In sum, the magnetic characterization of the ash layers has shown the occurrence of different post-burning alteration processes previously not identified at the site. Alteration processes in prehistoric combustion features are often identified from macroscopic observations but our study demonstrates that multiple processes can affect them and are usually unnoted because they take place on a microscopic scale. Their identification is critical for a correct chronological and cultural interpretation of a site (e.g. collection of samples for dating, stratigraphic displacement of remains), especially if significant alterations are involved. Magnetic methods are therefore a powerful but underutilized tool in palaeolithic research for the identification and evaluation of taphonomic processes affecting prehistoric fires.

New perspectives on human subsistence during the Magdalenian in the Swabian Jura, Germany

The Swabian Jura of southwestern Germany is famous for its Paleolithic sites which have been studied since the 1860s. While there is a rich tradition of research on the Magdalenian, many of the best-known sites were not excavated using modern methods, and recently, few discoveries of new sites have been made. Thus, much of the information on this period comes from sites lacking data collected using modern standards. This has left open questions regarding the recolonization of the Swabian Jura and hunter-gatherer subsistence and settlement during the Magdalenian in the region. Langmahdhalde is a recently discovered rock shelter in the Lone Valley of the Swabian Jura that has intact, well-stratified horizons dating to the Magdalenian with associated lithic artifacts, faunal remains, and combustion features. In this paper, we present a study of the faunal materials from this new site. We use the macrofaunal remains to discuss human subsistence and a taphonomic analysis of the microfaunal remains to determine the spatial scale of our previously published paleoenvironmental interpretations. Our results on human subsistence support previous interpretations from other Magdalenian assemblages in Central Europe. Further, our taphonomic study of the microfauna suggests that our paleoenvironmental analyses are relatively local, within a maximum of 70 km2 from the rock shelter. We place these results within the larger context of human paleoecology in the region and suggest that the successful resettlement of the Swabian Jura by Magdalenian peoples during the Late Glacial was probably facilitated by the presence of a higher diversity of resources on the landscape compared to regions to the west.

Assessing the Function of Palaeolithic Hearths: Experiments on Intensity of Luminosity and Radiative Heat Outputs from Different Fuel Sources

Assessing the function of Palaeolithic hearths is a key research issue that can benefit from the application of experimental archaeology when examining whether the behaviourally related purposes of fire, e.g. heat, light and cooking, could be correlated with combustion features in the archaeological record. Not all species of wood and types of fuel burn the same way. Variability exists in the amount of ash and smoke produced, along with differences in speed of burning and outgoing light and heat. This paper examined the light and heat properties of nine different types of fuels (eight individual species of wood and fresh bone) by assessing intensity of luminosity and radiative heat outputs using a lux metre and thermal imaging camera. Results show that there is considerable variation between bone and wood in terms of light and heat output and between the individual species of wood. In order to assess whether heat efficiency may vary seasonally, experiments were performed overnight and repeated at ambient air temperature ranges of 11 to 13 and 0 to 3 °C. Results show that in the current data set fuels that emit lower to intermediate heat outputs could be more efficient at colder temperatures in terms of warmth. This represents a preliminary step forward towards attributing behaviourally relevant functions such as light and heat to Palaeolithic combustion features with regard to fuel selectivity.