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221.
The 'Mardi Gras' Shipwreck is the remains of an early-19th-century sailing vessel lost in approximately 1220 m of water in the Gulf of Mexico. A recent archaeological investigation documented the wreck and recovered several artefacts, including glassware, ceramics, navigational instruments, a cannon, and a stove. Analyses of these artefacts and the surviving hull have led to preliminary conclusions on the nature of the vessel and its crew.
© 2009 The Authors  相似文献   
222.
Examination of stone artefacts from Maiden Castle, Dorset, led to the identification of a Neolithic saddle-quern which originated in central Normandy. While stone axes from Brittany and jadeitite axes from the Alps have long been known from central southern England, the quern is the largest and heaviest Neolithic import yet identified. It has a bearing on the debate about indigenous or immigrant origins for the Neolithic, but also re-opens the question of the type of boat that plied the Channel at this early period. It is argued that logboats, for which there is evidence, should not be overlooked in favour of skin-boats for which there is none.
© 2009 The Authors  相似文献   
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The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.  相似文献   
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Intensive agricultural systems interact strongly and reciprocally with features of the lands they occupy, and with features of the societies that they support. We modeled the distribution of two forms of pre-European contact intensive agriculture – irrigated pondfields and rain-fed dryland systems – across the Hawaiian archipelago using a GIS approach based on climate, hydrology, topography, substrate age, and soil fertility. Model results closely match the archaeological evidence in defined locations. On a broader scale, we calculate that the youngest island, Hawai'i, could have supported 572 km2 of intensive agriculture, 97% as rain-fed dryland field systems, while Kaua'i, the oldest island, could have supported 58 km2, all as irrigated wetland systems. Irrigated systems have higher, more reliable yields and lower labor requirements than rain-fed dryland systems, so the total potential yield from Kaua'i (49k metric tons) was almost half that of Hawai'i (97k metric tons), although Kaua'i systems required only 0.05 of the agricultural labor (8400 workers, versus 165,000 on Hawai'i) to produce the crops. We conclude that environmental constraints to intensive agriculture across the archipelago created asymmetric production efficiencies, and therefore varying potentials for agricultural surplus. The implications both for the emergence of complex sociopolitical formations and for anthropogenic transformation of Hawaiian ecosystems are substantial.  相似文献   
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