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Traditionally, strontium isotopes (87Sr/86Sr) have been used as a sourcing tool in numerous archaeological artifact classes. The research presented here demonstrates that 87Sr/86Srbioapatite ratios also can be used at a population level to investigate the presence of domesticated animals and methods of management. The proposed methodology combines ecology, isotope geochemistry, and behavioral ecology to assess the presence and nature of turkey (Meleagris gallopavo) domestication. This case study utilizes 87Sr/86Srbioapatite ratios from teeth and bones of archaeological turkey, deer (Odocoileus sp.), lagomorph (Lepus sp. and Sylvilagus sp.), and prairie dog (Cynomys sp.) from Chaco Canyon, NM, USA (ca. A.D. 800–1250). Wild deer and turkey from the southwestern USA have much larger home ranges and dispersal behaviors (measured in kilometers) when compared to lagomorphs and prairie dogs (measured in meters). Hunted deer and wild turkey from archaeological contexts at Chaco Canyon are expected to have a higher variance in their 87Sr/86Srbioapatite ratios, when compared to small range taxa (lagomorphs and prairie dogs). Contrary to this expectation, 87Sr/86Srbioapatite values of turkey bones from Chacoan assemblages have a much lower variance than deer and are similar to that of smaller mammals. The sampled turkey values show variability most similar to lagomorphs and prairie dogs, suggesting the turkeys from Chaco Canyon were consuming a uniform diet and/or were constrained within a limited home range, indicating at least proto-domestication. The population approach has wide applicability for evaluating the presence and nature of domestication when combined with paleoecology and behavioral ecology in a variety of animals and environments.  相似文献   
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When competition is naturally limited, policymakers craft regulation to obtain effects similar to those that would have occurred in the presence of competition. In many instances, regulation of this type is not successful in overcoming market failures. We rely on property rights theory and transaction cost theory to predict when state‐level policy statements will actually lead to a redistribution of benefits at the city level. We test this theory in the context of cable television franchise renewal agreements—a setting historically resistant to competition. We look to the language of the franchise agreements for evidence of concessions made by the cable operator to the city, and using a difference‐in‐difference estimator, we find that pro‐competitive regulation translates into concessions to the city. However, a credible threat of competition embedded in regulation is not enough to curb opportunism associated with monopoly supply in cases of large franchisees; larger cable operators are at least 60 percent less likely to offer more favorable terms of trade. However, consistent with transaction cost predictions, asset‐specific investments by the cable operator do curb opportunism; there is a 51 percent increase in the odds of a franchisee offering more concessions for a 1 standard deviation change—about 1,020 mi of the plant. These findings are important for those involved in crafting policy at all levels of government as well as for researchers interested in understanding the role of long‐term contracting and the use of hybrid mechanisms such as franchise agreements in contemporary governance.  相似文献   
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Archaeologists have generally avoided analyzing inorganic isotopes in bone because of its high porosity, large crystalline lattice spacing, and small crystallite size, making it particularly susceptible to diagenetic alteration. Because the inorganic isotopes are left unstudied, we lose a significant portion of information pertaining to an individual’s life history, such as migration, health, and ranging behavior. Tooth enamel, which does not have the same susceptibility to diagenesis as bone, can be used to extract this information but this means that taxa lacking teeth, such as birds, some species of fish, and some reptiles, are excluded. Here, we present a method that can be used to identify diagenetic alternation in bone. This is done by focusing on abnormal concentrations of vanadium and uranium. Neither element is readily bio-precipitated into hydroxyapatite due to ionic radius, vibrational frequency, atomic mass, and ionic charge. This makes them an ideal marker for diagenetically altered bone. Vanadium occurs in very low concentrations in modern bone, while archaeological bone shows clear evidence of normal, non-diagenetically altered values alongside high concentrations of vanadium in diagenetically altered bone. Uranium also is a measure of diagenetic alteration, as modern bone has concentrations below detectable limits (0.017 ppb), while some archaeological bone contains uranium above detectable limits. The biogeochemistry of these elements in soil and bone are discussed with implications for enamel studies.  相似文献   
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