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91.
We provide the first analysis of the fungi associated with a very special habitat, the aeroponic roots found in caves and mines in New Brunswick, Canada. Fungal diversity was assessed by Illumina sequencing using three complementary primer sets targeting ribosomal RNA genes, and roots were identified using the non-coding trnH-psbA spacer. Early colonizing ectomycorrhizal fungi such as Agaricales, Helotiales, Pezizales, and Thelephorales were predominant. Saprotrophs, endophytes and plant pathogens were also present, but Glomeromycota (arbuscular mycorrhizal fungi) were not detected. Fungal root communities were generally most similar within sites. Fungal diversity was inversely correlated with winter dark zone temperatures and distance from the entrance. By using a combination of three primer sets, we detected more fungal taxa than with any one primer set. This study adds to the understanding of these subterranean ecosystems and suggests that future studies investigate factors limiting the presence of late-stage ectomycorrhizal fungi and Glomeromycota.  相似文献   
92.
Excavations at Liang Bua, Flores, Indonesia, have yielded evidence for an endemic human species, Homo floresiensis, a population that occupied the cave between ∼95-17 ka. This discovery has major implications for early hominin evolution and dispersal in Africa and Asia, attracting worldwide interest. This preface describes the rationale for the excavations in historical, geographical, and wider research contexts, as well as the methods used. It also introduces the other papers on aspects of Liang Bua research that feature in this edition of the Journal of Human Evolution.  相似文献   
93.
Life history traits within species often vary among different habitats. We measured female fecundity in mollies (Poecilia mexicana) from a H2S-rich cave and from a neighbouring surface habitat, as well as in laboratory-reared individuals of both populations raised in either light or continuous darkness. Compared to conspecifics from surface habitats, cave-dwelling P. mexicana had reduced fecundity (adjusted for size) in the field. In the laboratory, the fecundity of surface mollies was higher in light than in darkness, whereas fecundity in the cave mollies was almost unaffected by the ambient light conditions. Our results suggest a heritable component to the reduction in fecundity in female cave mollies. Moreover, the reduced plasticity in fecundity of cave mollies in response to light conditions might be an example of genetic assimilation or channelling of a life history trait in a population invading a new environment.  相似文献   
94.
Erika Gál 《Geobios》2008,41(1):79
The paper presents a faunal and taphonomic discussion of the Late Pleistocene bird-bone assemblages excavated in Kálvária Cave no 4 near the city of Tatabánya in north-west Hungary. A total of 1150 complete and fragmentary avian remains were recovered from two locations on two separate occasions. Of these, 873 bones could be identified on the species-, family- or order-level. Fifteen of the identified 19 bird taxa could be determined on the species level and they indicate a habitat typical of forest margins. Several species yielded juvenile or subadult specimens, which in view of the breeding period means that these birds died during the summer, most probably between July and September.Each of the two assemblages had distinct characteristics. The high number of kestrel (Falco tinnunculus) long bones in Assemblage I generally included complete skeletal parts from subadult birds, suggesting a colony which bred in the cave, whose chicks died of natural causes. Even though the bones were exposed to a certain degree of water transport and soil corrosion, they were generally well preserved in the cave sediment. Size-characteristic analyses demonstrated that, in spite of the undeveloped morphological features, the sizes of limb bones usually corresponded to those of adult birds.The greater part of the material in Assemblage II originated from a stratified deposit and was dominated by small and fragmented remains of various taxa. The taxa which could be identified and the taphonomic features of the remains suggest that owl pellets formed the core of this bone assemblage.  相似文献   
95.
2008年12月在贵州毕节团结乡首次发现麻窝口洞化石点,经2009年、2012年和2013年3次发掘,在麻窝口洞上部砂质黏土地层中共发现了四千余件哺乳动物牙齿化石。2013年7月发现的3枚古人类牙齿,分别为左上犬齿、左上第一臼齿和右上第二臼齿。人类牙齿尺寸偏小,臼齿咬合面沟纹简单,没有复杂的咬合面皱纹和附尖齿带结构,牙根短而不显粗壮,上述特点有别于我国已经发现的直立人和早期智人,可归入解剖学上的现代人。与人类相伴的哺乳动物化石,经初步鉴定共计8目20科43属53种,动物群组合反映出亚热带森林生态环境。根据动物群的时代特点,地貌地层及堆积物的光释光年代测定,指示毕节麻窝口洞古人类的时代可能为中更新世晚期,或者晚更新世早期,毕节古人类牙齿的发现为东亚地区现代人的起源及演化增添了新的证据。  相似文献   
96.
牛亚科动物在中国第四纪古人类遗址中十分常见,但其分类和鉴定仍存在诸多问题。南方洞穴动物群经常仅有单个牙齿保存,所以南方更新世洞穴遗址中牛亚科动物化石鉴别问题更为突出。湖北郧西白龙洞古人类遗址出土的大型牛亚科动物化石,不仅有大量单个牙齿,还有残破颅骨、角心、下颌骨及头后骨骼。白龙洞的牛亚科动物角心粗短、横截面呈背腹略扁的椭圆形;额骨上的角间隆突发育且呈拱形;顶骨从颅顶退出;枕面较圆且高;角后颅骨收缩强烈使得枕骨上部变窄,颞窝明显凹进;下颌角大于90°,下颌支向后倾斜;下颌p2的结构复杂程度介于水牛Bubalus和黄牛Bos(Bos)taurus之间。依据上述特征,可将白龙洞的大型牛亚科动物化石归入大额牛Bos(Bibos)gaurus。白龙洞是我国出土大额牛化石最为丰富的古人类遗址,为区分南方洞穴出土的牛亚科动物化石提供了重要材料。  相似文献   
97.
湖北郧西黄龙洞更新世晚期人类牙齿磨耗与使用痕迹   总被引:1,自引:0,他引:1  
对2004—2006年在黄龙洞发现的7枚人类牙齿磨耗与使用痕迹的观察显示: 除具有正常牙齿相互接触造成的磨耗外, 黄龙洞人类牙齿还呈现出一些特殊的使用痕迹, 包括明显的前部牙齿釉质破损与崩裂、上颌侧门齿齿冠唇面釉质破损、上颌前部牙齿齿间邻接面沟等。根据这些牙齿使用痕迹集中在前部牙齿, 釉质破损与崩裂主要分布在靠近切缘的上颌门齿唇面及下颌门齿舌面的情况, 推测生活在黄龙洞的更新世晚期人类经常使用前部牙齿从事啃咬、叼衔、或剥离等动作, 并可能将前部牙齿作为工具使用。分布在前部牙齿的齿间邻接面沟提示当时人类经常从事剔牙活动。黄龙洞人类前部牙齿的使用痕迹与当时人类获取、处理及食用附着在骨骼上的筋或肉的动作密切相关, 当时人类的食物构成中可能包含有较多的肉类及粗纤维植物。  相似文献   
98.
河南织机洞旧石器遗址的洞穴堆积和沉积环境分析   总被引:1,自引:0,他引:1  
MIS3阶段晚期是末次冰期中一个气候比较温暖的间冰阶,当时人类活动相当活跃,在世界各地这一时期的人类文化遗址不仅数量多,而且文化面貌也发生明显的变化。织机洞遗址是一处以旧石器时代中晚期为主的洞穴遗址,洞穴中堆积地层可以划分为四层:下部含丰富的打制石器称下文化层,属旧石器中晚期;中部不含石器;上部含少量打制石器称中文化层,属旧石器晚期;顶部含有裴李岗和秦汉时期的文化遗存称上文化层,属全新世时期。根据光释光年代测定,文化遗存最为丰富的下文化层,年龄为距今3·5—5万年,相当于MIS3阶段的中晚期,正处于"旧石器晚期革命"的前夕。孢粉分析结果表明,下文化层所处的MIS3阶段气候比较温暖湿润,为暖温带草原-疏树草原环境,良好的气候环境有利于当时古代人类的生存与繁衍。  相似文献   
99.
周口店田园洞大中型哺乳动物记述   总被引:6,自引:2,他引:4  
田园洞古人类化石地点含不少动物化石,其中主要为大中型哺乳动物,并以鹿类为主。除一枚残破鬣狗牙齿以外,目前在此所发现的材料全可归入现生种。该地点主体堆积的地质时代可能与周口店山顶洞动物群同期。本化石组合中有几个种现在已经离开本地区,如貂、黑熊、香麝、梅花鹿、马鹿、牛及鬣羚等,它们可能代表了这些动物在北京地区的最晚记录。但有些动物却是北京地区的首次发现,例如猪獾和鬣羚。  相似文献   
100.
Abstract: Home-range size and population abundance indices of coyotes (Canis latrans) have not been documented in Wind Cave National Park, South Dakota, USA. In 2003 and 2004, we captured a total of 26 coyotes and radiocollared 22 adults (12 F, 10 M). In 2003 and 2004, 2 of 17 (12%) and 5 of 9 (56%) coyotes, respectively, were infected with sarcoptic mange (Sarcoptes scabiei) at the time of capture. Thus, objectives were modified to document effects of the mange epizootic on the coyote population. In 2003, home-range (adaptive-kernel) sizes for male coyotes with mange and those considered healthy were 8.26 ± 1.63 (SE) km2 and 9.67 ± 2.80 km2, respectively. In 2004, home-range sizes for those male coyotes with and without mange were 22.69 ± 9.06 km2 and 12.51 ± 2.73 km2, respectively. Male home-range size did not differ between years (P = 0.14) or by status (with or without mange; P = 0.84). Survival of collared coyotes was 60% at the end of 2003. Results from fecal line transects, an index of relative abundance, indicated that the coyote population decreased by 48% from 2003 to 2004. Continued monitoring of sarcoptic mange epizootics will enable managers to assess the effects of mange on coyote populations.  相似文献   
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