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While rapid fertility decline in India in the last two decades has received considerable attention, much of the discourse has focused on a decline in high parity births. However, this paper finds that, almost hidden from the public gaze, a small but significant segment of the Indian population has begun the transition to extremely low fertility. Among the urban, upper income, educated, middle class, it is no longer unusual to find families stopping at one child, even when this child is a girl. Using data from the India Human Development Survey of 2004–2005, we examine the factors that may lead some families to stop at a single child. We conclude that the motivations for this very low fertility are likely to be a more extreme form of those for low fertility rather than reflecting the qualitative change in ideologies and worldviews that is hypothesized to accompany very low fertility during the second demographic transition. 相似文献
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Separating two or more aspects of an object via cutting was likely an important factor in the origin and evolution of flaked stone technology. In recent years experiments have demonstrated that several stone tool attributes can influence different kinds of cutting behaviour: slicing, cleaving, scraping, sawing, drilling, piercing and abrading. Here we experimentally assessed the role of stone flake plan- and profile-view gross-edge curvature in a controlled slicing task. We also assessed the role of edge length. A total of 21 participants, using 252 stone flakes with distinct gross-edge curvatures and edge lengths, were asked to cut through a standardized substrate, and their efficiency in the task was measured over time. Flakes with longer edge lengths increased the efficiency of the cutting task, but increasing either plan- or profile-view edge curvature decreased the efficiency of the cutting task. These results have implications for the emergence of particular tool forms or reduction sequences throughout the Pleistocene, and may in part explain why certain forms were favoured by Paleolithic people, leading to their convergent evolution or widespread transmission. 相似文献
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