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61.
Behavioral depression is a decline in prey availability because of enhanced alert response, movement away from areas, increased social behavior, and other responses to predators. This form of resource depression is an alternative hypothesis to be contrasted to over-exploitation that potentially explains a decrease in hunting efficiency over time should the zooarchaeologist observe a decline in the relative abundance of remains of high-rank prey. Gregarious ungulates, such as many North American cervids, may exhibit such behavioral responses under predation. The white-tailed deer (Odocoileus virginianus), one of the most common high-rank prey animals from Holocene archaeological sites in eastern North America, is less gregarious, more r-selected, and exhibits greater home-range fidelity than other cervids. As a result, whitetails are less likely to exhibit behavioral depression than other North American ungulates, which may explain their common occurrence in Holocene archaeological faunas, such as that from the Eagle??s Ridge site in southeast Texas where resource depression appears to have occurred from 4,500 to 1,500?years ago. The behavioral ecology of ungulate species should be considered on a case-by-case basis to develop testable hypotheses about prehistoric human predation.  相似文献   
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Inter-organizational collaboration as a means for policy coordination has come to be seen as a solution to difficult and complex urban challenges. In Portugal, where metropolitan governance structures are highly fragmented, critics highlight the need for better coordination between municipalities—a situation typical in many countries. We seek to understand the forces behind the emergence of inter-municipal collaboration around land use and mobility issues, using a case study method. Based on nine cases from Portugal's two largest metropolitan areas, we test a model of inter-municipal collaboration, attempting to identify the factors and conditions which contribute to the emergence of collaborative relationships. The analysis suggests several points of validation as well as propositions for extending and refining the model. We find that collaboration is facilitated by a combination of positive incentives, ambiguity and flexibility in the institutional system, an external catalyst, existing inter-organizational networks, and specific organizational characteristics. The existence of any one of these factors is not enough. A combination of several factors, possible but apparently uncommon in Portugal, is necessary. This research suggests that the Portuguese planning system may be most likely to achieve metropolitan policy coordination through a metropolitan association that can incentivize collaborative projects.  相似文献   
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Between about 500 a.d. and the late nineteenth century, clay cooking pots associated with the Thule culture were produced in the Arctic region. Ethnographic and archaeological records indicate that these vessels were typically underfired (often even unfired), highly porous, and easily broken. Despite these characteristics, the evidence indicates that they were used to heat water over open fires. In this paper, we examine how Arctic potters were able to produce unsintered vessels capable of holding liquids without disintegrating. We conclude that the application of seal oil and seal blood to the pot’s surface was the key to their success.
Karen G. HarryEmail:
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When adequate data on migration are unavailable, demographers infer such data indirectly, usually by turning to residual methods of estimating net migration. This paper sets out and illustrates an inferential method that uses population totals in the first age group of birthplace‐specific counts of residents in each region of a multiregional system to indirectly infer the entire age schedule of directional age‐specific migration flows. Specifically, it uses an estimate of infant migration that is afforded by a count of infants enumerated in a region other than their region of birth to infer all other age‐specific migration flows. Since infants migrate with their parents, the migration propensities of both are correlated, and the general stability of the age profiles of migration schedules then allows the association to be extended to all other age groups.  相似文献   
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Phrygian Gordion was the political center of an influential Iron Age polity that extended across west central Anatolia during the first half of the 1st millennium BC. Though the borders of this polity remain vague a characteristic of the Phrygian “footprint” is the distribution of highly distinctive ceramics. The extent to which Gordion potters were the originators of these wares remains uncertain. In this paper we use Neutron Activation Analysis (NAA) to establish the local signature of predominantly Iron Age ceramics for this site by combining samples from several decades of excavation with an extensive regional sediment sequence. We also compare previous NAA work at Gordion to suggest that the formative stages of the Phrygian state appears to have involved a more extensive network of non-local specialist producers than previously thought.  相似文献   
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Unborn in the USA traces the activities of antiabortion activistsin thirty-five states, documenting a range of antichoice activism,from exhibiting photo displays of aborted fetuses to a folkartist who creates life-sized sculptures of fetuses at variousdevelopmental stages. It offers only one side in the abortionwar—those opposed to the procedure—and only thosewho attempt to derail support for abortion by presenting imagesof aborted fetuses, even though, curiously, the  相似文献   
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