Journey to the east: Diverse routes and variable flowering times for wheat and barley en route to prehistoric China.

Today, farmers in many regions of eastern Asia sow their barley grains in the spring and harvest them in the autumn of the same year (spring barley). However, when it was first domesticated in southwest Asia, barley was grown between the autumn and subsequent spring (winter barley), to complete their life cycles before the summer drought. The question of when the eastern barley shifted from the original winter habit to flexible growing schedules is of significance in terms of understanding its spread. This article investigates when barley cultivation dispersed from southwest Asia to regions of eastern Asia and how the eastern spring barley evolved in this context. We report 70 new radiocarbon measurements obtained directly from barley grains recovered from archaeological sites in eastern Eurasia. Our results indicate that the eastern dispersals of wheat and barley were distinct in both space and time. We infer that barley had been cultivated in a range of markedly contrasting environments by the second millennium BC. In this context, we consider the distribution of known haplotypes of a flowering-time gene in barley, Ppd-H1, and infer that the distributions of those haplotypes may reflect the early dispersal of barley. These patterns of dispersal resonate with the second and first millennia BC textual records documenting sowing and harvesting times for barley in central/eastern China

Correction: Journey to the east: Diverse routes and variable flowering times for wheat and barley en route to prehistoric China.

[This corrects the article DOI: 10.1371/journal.pone.0187405.]

Stable isotopic composition of rice grain organic matter marking an abrupt shift of hydroclimatic condition during the cultural transformation of Harappan civilization

Several hypotheses have been proposed to solve the conundrum of the cause of transition of Harappan civilization to a de-urbanized form in its Late Phase. In view of this, high-resolution off-site palaeoclimatic records along with archaeological findings provide strong evidence of an abrupt climate change similar to 4000 yr BP (before present) that coincides with the civilization's cultural transition. The present study investigates whether this climatic shift recorded in palaeoclimate archives (speleothem, lake and marine sediments) at remote locations can be traced to the human settlements of Harappan civilization. This was accomplished by analyzing the remains of rice cereal-a highly water sensitive crop. The analysis involved measuring carbon and nitrogen isotopic compositions (delta C-13, delta N-15) of well-preserved rice grains recovered from archaeological sites belonging to the Harappan civilization and other contemporary regional cultures, representing the time windows between 4520 and 3400 yr BP. The parameter of intrinsic water use efficiency (WUEi) was used as an index for water availability in the rice crop's growth environment and was ascertained based on delta C-13 values measured in the bulk grain organic matter (OM). The observed WUEi values ranged between 49 and 69 mu mol mol(-1) and captured the variation in water availability. The delta N-15 values ranged from 5 parts per thousand to 6.5 parts per thousand, thereby allowing us to confirm the role of climate in controlling delta C-13 variation in the archaeological grains. The present findings will extend the usage of archaeobotanical cereal remains to deduce environmental changes at human settlements and will further our understanding of the process of Harappan cultural adaptation in response to decline in southwest monsoon at the Middle-Late Holocene boundary

Modern botanical analogue of endangered Yak (Bos mutus) dung from India: Plausible linkage with extant and extinct megaherbivores.

The study reports the micro- and macrobotanical remains on wild Yak dung, providing evidence for understanding the diet, habitat, and ecology of extant and extinct megaherbivores. Grasses are the primary diet of the yak as indicated by the abundance of grass pollen and phytoliths. Other associated non-arboreal and arboreal taxa namely, Cyperacaeae, Rosaceae, Chenopodiaceae, Artemisia, Prunus, and Rhododendron are also important dietary plants for their living. The observation of plant macrobotanical remains especially the vegetative part and seeds of the grasses and Cyperaceae is also in agreement with the palynodata. The documented micro- and macrobotanical data are indicative of both Alpine meadow and steppe vegetation under cold and dry climate which exactly reflected the current vegetation composition and climate in the region. The recovery of Botryococcus, Arcella, and diatom was observed in trace amounts in the palynoassemblage which would have been incorporated in the dung through the ingestion of water and are indicative of the presence of perennial water system in the region. Energy dispersive spectroscopy analysis marked that the element contained in dung samples has variation in relation to the summer and winter, which might be due to the availability of the food plants and vegetation. This generated multiproxy data serves as a strong supplementary data for modern pollen and vegetation relationships based on surface soil samples in the region. The recorded multiproxy data could also be useful to interpret the relationship between the coprolites of herbivorous fauna and the palaeodietary, the palaeoecology in the region, and to correlate with other mega herbivores in a global context

Altered cropping pattern and cultural continuation with declined prosperity following abrupt and extreme arid event at ~4,200 yrs BP: Evidence from an Indus archaeological site Khirsara, Gujarat, western India - Fig 2

<p>Archaeological artifacts recovered from Khirsara (A) Mature Harappan ceramics (painted and plain) (B) Red Ware Harappan pot (C) Gold beads (D) Fish hook made of copper (E) Copper objects (F) Beads of semiprecious stones (G) Seal with bison (H) Seal bearing Harappan characters. These antiquities have been stored at the office of Excavation Branch-V, ASI, Vadodara, Gujarat, India.</p

¹⁴C dates of wood-charcoal measured by conventional beta counting method at BSIP.

<p>¹⁴C dates of wood-charcoal measured by conventional beta counting method at BSIP.</p

AMS measured ¹⁴C dates of agricultural grains (Barley and Wheat respectively) from the trench Z-38.

<p>AMS measured ¹⁴C dates of agricultural grains (Barley and Wheat respectively) from the trench Z-38.</p

Left panels show pie-charts displaying relative abundance of crop plants and right panels show corresponding histograms for three distinct phases of overall subsistence changes in the archaeological site Khirsara.

<p>Left panels show pie-charts displaying relative abundance of crop plants and right panels show corresponding histograms for three distinct phases of overall subsistence changes in the archaeological site Khirsara.</p

Photograph of trench AF-35 from where samples were taken for C isotope analysis.

<p>Right panel shows stratigraphic appearances with finds of archaeological artefacts. Depth-profiles of TOC (wt.%) and δ¹³C_TOC of the trench AF-35 is shown in lower panels. Calibrated ¹⁴C age based chronological constraints are shown as + symbols.</p