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61.
The Mesolithic–Neolithic transition in north-west Europe has been described as rapid and uniform, entailing a swift shift from the use of marine and other wild resources to domesticated terrestrial resources. Here, we approach the when, what and how of this transition on a regional level, using empirical data from Öland, an island in the Baltic Sea off the Swedish east coast, and also monitor changes that occurred after the shift. Radiocarbon dating and stable carbon and nitrogen isotope analyses of bones and teeth from 123 human individuals, along with faunal isotope data from 27 species, applying to nine sites on Öland and covering a time span from the Mesolithic to the Roman Period, demonstrate a great diversity in food practices, mainly governed by culture and independent of climatic changes. There was a marked dietary shift during the second half of the third millennium from a mixed marine diet to the use of exclusively terrestrial resources, interpreted as marking the large-scale introduction of farming. Contrary to previous claims, this took place at the end of the Neolithic and not at the onset. Our data also show that culturally induced dietary transitions occurred continuously throughout prehistory. The availability of high-resolution data on various levels, from intra-individual to inter-population, makes stable isotope analysis a powerful tool for studying the evolution of food practices.  相似文献   
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The focus of this article is on product innovations introduced by firms (establishments) and the collaborations they enter into with other firms and organizations in carrying out this activity. The theoretical framework combines innovation theories with the literature on regional innovation systems and the knowledge-based economy. Empirically we have investigated characteristics of collaboration among manufacturing establishments in the region of East Gothia in Sweden, with specific focus on the number of employees involved in the innovation projects, mechanisms of knowledge transfer between organizations, as well as financing and patenting in relation to product innovations.  相似文献   
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The aim of this paper is to provide a summary of structural or surface modifications of vertebrate bone remains in continental palaeoenvironments that may have repercussions on their chemical composition. Both before and after burial, a different set of physical, chemical and biological agencies may produce modifications of the bone morphological structure and/or bone chemical composition. Several of these morphological modifications are diagnostic of particular agents, which otherwise may not be noticed or identified in a fossil association. In order to understand diagenesis, those events that occurred before final burial have to be considered, as they may strongly modify the bone morphological structure and influence post–burial changes.  相似文献   
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Most anthropologists would agree that humans are simultaneously historical, biological, behavioral, and social. However, many researchers retain a relatively dualistic paradigm dividing anthropological questions into biological and/or social aspects. Many practitioners of Neo-Darwinian perspectives prioritize natural selection in all explanations of human evolution. Many other anthropologists refuse to acknowledge a significant role for biological features and biological histories in human action, sensation, and engagement. Both perspectives are misplaced. Incorporating emerging perspectives in evolutionary theory into the broader anthropological discourse may help discard simplistic dualisms and resituate our assessments of the evolution of human behavior. In this essay I review three major emergent themes in evolutionary theory; Multi-Inheritance Systems Theory, Developmental Systems Theory, and Niche Construction. I suggest, with one brief example, that placing these elements in transaction with other perspectives in anthropology might enhance the possibilities of assessing human evolution and behavior.  相似文献   
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Archaeological evidence shows that populations used to transverse the Sahara Desert throughout the Holocene despite the extreme temperatures and the rough physical terrain. The current paper examines whether the desert inhibited extended gene flow among populations by means of cranial morphology as captured by geometric morphometrics. The examined populations include the Garamantes, a group centered in Southwest Libya and largely controlling trans-Saharan trade, and various Egyptian, Tunisian and Sudanese groups dating to the Middle and Late Holocene. The results showed that most inter-population comparisons were statistically significant and therefore all populations appear more or less distant to each other. The Mahalanobis biodistance measure identified four clusters. The first consists of the Garamantes alone, the second includes the populations from Kerma and Gizeh, the third includes the Badari and Naqada, while the fourth consists of the samples from Algeria, Carthago, Soleb and Alexandria. Moreover, the distance of the Garamantes to their neighbors was significantly high and the population appeared to be an outlier. This is attributed to the location of the Garamantes at the core of the desert, indicating that, despite the archaeological evidence, the Sahara Desert posed important limitations to gene flow between the Garamantes and other North African populations.  相似文献   
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The phenomenon of equifinality complicates behavioral interpretations of faunal assemblages from contexts in which Pleistocene hominins are suspected bone accumulators. Stone tool butchery marks on ungulate fossils are diagnostic of hominin activities, but debate continues over the higher-order implications of butchered bones for the foraging capabilities of hominins. Additionally, tooth marks imparted on bones by hominins overlap in morphology and dimensions with those created by some non-hominin carnivores, further confounding our view of early hominins as meat-eating hunters, scavengers or both. We report on the manual/oral peeling of cortical layers of ungulate ribs as taphonomically diagnostic of hominoid/hominin meat- and bone-eating behavior that indicates access to large herbivore carcasses by hominins at the site of BK, Olduvai. Supporting these inferences, we show that certain types of rib peeling damage are very rare or completely unknown in faunas created by modern carnivores and African porcupines, but common in faunas modified by the butchery and/or consumption activities of modern humans and chimpanzees, during which these hominoids often grasp ribs with their hands, and then used their teeth to peel strips of cortex from raggedly chewed ends of the ribs. Carnivores consume ungulate ribcage tissues soon after kills, so diagnostic traces of hominin butchery/consumption on ribs (i.e., peeling and butchery marks) indicate early access to ungulate carcasses by BK hominins. Tooth marks associated with the peeling and butchery marks are probably hominin-derived, and may indicate that it was not uncommon for our ancestors to use their teeth to strip meat from and to consume portions of ribs. Recognition of rib peeling as a diagnostic signature of hominoid/hominin behavior may also aid the search for pre-archaeological traces of hominin meat-eating.  相似文献   
70.
Patent Places: Size Matters   总被引:5,自引:0,他引:5  
In this paper I investigate the United States urban system of technical advance by analysis of metropolitan patent data. Residents of metropolitan areas obtain most of the patents awarded to Americans and the largest areas predominate, signifying that urbanization externalities facilitate invention. The advantages of large areas arise from lopsided concentrations of technologically intensive manufacturing and an uneven distribution of well-educated people. Location with respect to the traditional manufacturing belt also plays a role. Metropolitan residents in the manufacturing belt remain the most industrious inventors. The contribution of leading educational and research institutions to technical advance is manifest in small urban centers and outside the traditional manufacturing belt.  相似文献   
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