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11.
The investigation of a limestone cave on the Ryonggok-ri of Sangwon County, North Hwanghae Province, DPRK, has yielded many faunal remains including Late Pleistocene deer, brown bears and horses. Uranium series dating of fossil teeth yielded dates of ~72ka at the base of Layer 2 – the bone-bearing unit – and ~44ka at the top. The rich and diverse mammal remains of Ryonggok Cave No. 1 are indicative of warm and humid temperate conditions during the Late Pleistocene, and reflect the presence of both dense forests and open grassland. In addition, pollen and spores from the site include two families and 24 genera of trees, six families and a genus of grasses and herbs, and two families and six genera of ferns, corroborating the environments inferred from the faunal remains.  相似文献   
12.
The NW–SE shortening between the African and the Eurasian plates is accommodated in the eastern Betic Cordillera along a broad area that includes large N‐vergent folds and kilometric NE–SW sinistral faults with related seismicity. We have selected the best exposed small‐scale tectonic structures located in the western Huércal‐Overa Basin (Betic Cordillera) to discuss the seismotectonic implications of such structures usually developed in seismogenic zones. Subvertical ESE–WNW pure dextral faults and E–W to ENE–ESW dextral‐reverse faults and folds deform the Quaternary sediments. The La Molata structure is the most impressive example, including dextral ESE–WNW Neogene faults, active southward‐dipping reverse faults and associated ENE–WSW folds. A molar M1 assigned to Mimomys savini allows for precise dating of the folded sediments (0.95–0.83 Ma). Strain rates calculated across this structure give ~0.006 mm a?1 horizontal shortening from the Middle Pleistocene up until now. The widespread active deformations on small‐scale structures contribute to elastic energy dissipation around the large seismogenic zones of the eastern Betics, decreasing the seismic hazard of major fault zones. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
13.
Precipitation and net primary productivity are positively correlated in arid environments. Both variables are, in turn, correlated with mammal species richness, but this relationship is not necessarily positive. With increasing precipitation in arid areas of low to moderate productivity, mammal richness increases linearly; as rainfall and productivity increase beyond this point, mammal richness is known to decline in some areas, producing a relationship that has been termed “unimodal” or “humped.” In the Great Basin of the arid western United States, studies of the relationship between rodent species richness and precipitation have revealed only a positive relationship between these two variables. It has, however, been argued that if areas of higher precipitation were to be sampled within this region, the decline phase would become evident. When latest Pleistocene and Holocene small mammal assemblages from the northern Bonneville Basin (central Utah) are examined across a temporal moisture gradient, species richness declines as moisture declines. Since the Great Basin was significantly moister during the latest Pleistocene and Early Holocene than it has been since that time, the unimodal response model does not appear to apply to this region.  相似文献   
14.
In a recent article in this journal (Butterworth and Richardson. A review of animal welfare implications of the Canadian commercial seal hunt. Marine Policy 2013;38:457–469), the authors argued that “generally accepted principles of humane slaughter cannot be carried out effectively or consistently during the Canadian commercial seal hunt”. The present review purports to show that these authors' conclusions were incorrect because they were highly selective in their treatment of the information available and made no attempt to consider other perspectives. In addition, their reliance on anecdotal video sequences to support some of their points was seriously flawed since a vast proportion of these sequences failed to meet fundamental criteria of scientific rigor. The article by Butterworth and Richardson [5] failed to provide an unbiased presentation of the available data and therefore did not bring further clarity to the debate on the Canadian commercial seal hunt.  相似文献   
15.
Data on the occurrence and accumulation profiles of butyltins (BTs), including tributyltin (TBT), in marine mammals are scarce. This is the first study to investigate residue levels and accumulation patterns of BTs in cetaceans from Korean coastal waters. The total concentrations of BTs (sum of mono- to tri-butyltins) in minke whales (Balaenoptera acutorostrata) and long-beaked common dolphins (Delphinus capensis) ranged from 15.7 to 297 ng/g wet weight (mean: 100 ng/g wet weight) and from 59.0 to 412 ng/g wet weight (mean: 228 ng/g wet weight), respectively. Dibutyltin (DBT) accounted for 63% of the total BTs in all cetacean samples. Significant species-specific differences in BT concentrations, possibly due to the differences in their habitat and diet, were found between the two cetacean species. The concentrations of DBT and TBT in most cetacean samples exceeded the threshold value for cytotoxic effects in cetaceans, implying potentially adverse health risks from exposure to BTs.  相似文献   
16.
A mandible identified as noble marten (Martes americana nobilis) recovered from sediments dating to 11,800 cal yr BP and a humerus identified as M. a. cf. nobilis recovered from sediments dating from 13,100 to 12,500 cal yr BP at the Marmes Rockshelter archaeological site in southeastern Washington represent the first record of this taxon in the state. Mammalian taxa associated with the Marmes Rockshelter noble marten represent a diversity of open mesic habitats corroborating earlier analyses of other records of the noble marten in the western United States and exemplify how paleozoologists determine the ecology and environmental predilections of extinct taxa. The recovery site represents the topographically lowest record of this species in western North America and the farthest north record in the United States. Future research should examine known late-Quaternary Martes spp. remains from British Columbia and Alberta to fill in the 2200-km geographic gap in the known distribution of this taxon between a record in the northern Yukon and those in the western United States, and to refine our knowledge of noble marten paleoecology.  相似文献   
17.
In a recently published paper, Agardy et al. [Mind the gap: addressing the shortcomings of marine protected areas through large scale marine spatial planning. Marine Policy 2011;35:226-32] discuss the shortcomings of several Marine Protected Areas (MPAs) including the Gully MPA, located 200 km offshore Nova Scotia, Canada. Although the paper's critical assessment of MPA effectiveness was welcomed, the Gully MPA received an out-of-date profile resulting in an erroneous analysis of current protection levels. This short communication has been written to set the record straight.  相似文献   
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19.
岭南东江流域晚更新世哺乳动物化石的新发现   总被引:5,自引:1,他引:5       下载免费PDF全文
近年在南岭以南的广东东江流域河源地区东源县上莞镇的碧寿洞中发现较丰富的古哺乳动物牙齿化石。经鉴定为6个目5属5种,称之为碧寿动物群。根据碧寿动物群指示的古生态、化石层位、热释光测试结果和生物地层对比初步认为,该动物群与西江流域的罗沙岩动物群一样,都属于晚更新世时期的大熊猫—剑齿象动物群,生活在MIS5a时的间冰期,但罗沙岩动物群的时代略早,为(79.0±15)kaBP,而碧寿动物群则存在于末次冰期/末次间冰期之交的MIS5a之末叶。此动物群为广东东江流域历年首现,代表了当时的热带北缘森林草原的自然环境。  相似文献   
20.
贵州毕节发现的巨猿牙齿化石及其意义   总被引:3,自引:0,他引:3       下载免费PDF全文
文章报道了发现于贵州毕节的一枚巨猿牙齿化石,介绍了巨猿化石发现的历史过程及与之相关的毕节扒耳岩早更新世哺乳动物化石。贵州毕节巨猿化石的发现,填补并扩大了巨猿化石的地史分布范围,对研究巨猿演化及云贵高原地质环境变化等相关问题有着重要意义。  相似文献   
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