Early evidence for the use of wheat and barley as staple crops on the margins of the Tibetan Plateau

We report directly dated evidence from circa 1400 calibrated years (cal) B.C. for the early use of wheat, barley, and flax as staple crops on the borders of the Tibetan Plateau. During recent years, an increasing amount of data from the Tibetan Plateau and its margins shows that a transition from millets to wheat and barley agriculture took place during the second millennium B.C. Using thermal niche modeling, we refute previous assertions that the ecological characteristics of wheat and barley delayed their spread into East Asia. Rather, we demonstrate that the ability of these crops to tolerate frost and their low growing degree-day requirements facilitated their spread into the high-altitude margins of western China. Following their introduction to this region, these crops rapidly replaced Chinese millets and became the staple crops that still characterize agriculture in this area today

Scale and information-processing thresholds in Holocene social evolution

Throughout the Holocene, societies developed additional layers of administration and more information-rich instruments for managing and recording transactions and events as they grew in population and territory. Yet, while such increases seem inevitable, they are not. Here we use the Seshat database to investigate the development of hundreds of polities, from multiple continents, over thousands of years. We find that sociopolitical development is dominated first by growth in polity scale, then by improvements in information processing and economic systems, and then by further increases in scale. We thus define a Scale Threshold for societies, beyond which growth in information processing becomes paramount, and an Information Threshold, which once crossed facilitates additional growth in scale. Polities diverge in socio-political features below the Information Threshold, but reconverge beyond it. We suggest an explanation for the evolutionary divergence between Old and New World polities based on phased growth in scale and information processing. We also suggest a mechanism to help explain social collapses with no evident external causes

Bioclimatic design for informal settlements

In this paper, a review of the reasons hindering the use of bioclimatic design principles in informal settlements is attempted and the perspective of bioclimatic design in those contexts is discussed. Among the main candidate reasons is the habit of mind induced by the belief that informal settlements grow organically, so as to invariably end up being optimized for their functional tasks. Another reason lies in the very nature of bioclimatic design, which is based on integration, that can be perceived as too a “weak” guarantee of perspective features, not very suitable for competing with clear-cut and powerful strategies like active climatic control. A third reason is constituted by the technical challenges which are presently still posed by the environmental simulation of open and intermediate spaces, especially in hot climatic conditions. In this context, some promising research lines related to climatic control and passive cooling are identified in this text. Those approaches are likely to benefit from an integrated blend of practice and theory and may contribute to increase the attractiveness of bioclimatic principles for the rehabilitation of informal settlements

Climate Change and the Rise and Fall of the Oxus Civilization in Southern Central Asia

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