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71.
A low diversity Lower Ordovician trilobite assemblage is described from the middle part of the Lashkarak Formation at Simeh-Kuh, northwest of Damghan, northern Iran. Co-occurrence with conodonts of the lowermost Paroistodusproteus Biozone suggests an uppermost Tremadocian age. This assemblage includes four taxa, including one new genus and two new species, Damghanampyxginteri nov. gen. nov. sp. and Asaphellusfecundus nov. sp. The third diagnosable species from the formation is Taihungshaniamiqueli (Bergeron, 1894) which has previously been reported from southern France and the Turkish Taurides, suggesting north Gondwanan faunal affinities. 相似文献
72.
Merijn M. Bos Ingolf Steffan-Dewenter Teja Tscharntke 《Biodiversity and Conservation》2007,16(8):2429-2444
The ongoing destruction of tropical rainforests has increased the interest in the potential value of tropical agroforests
for the conservation of biodiversity. Traditional, shaded agroforests may support high levels of biodiversity, for some groups
even approaching that of undisturbed tropical forests. However, it is unclear to what extent forest fauna is represented in
this diversity and how management affects forest fauna in agroforests. We studied lower canopy ant and beetle fauna in cacao
agroforests and forests in Central Sulawesi, Indonesia, a region dominated by cacao agroforestry. We compared ant and beetle
species richness and composition in forests and cacao agroforests and studied the impact of two aspects of management intensification
(the decrease in shade tree diversity and in shade canopy cover) on ant and beetle diversity. The agroforests had three types
of shade that represented a decrease in tree diversity (high, intermediate and low diversity). Species richness of ants and
beetles in the canopies of the cacao trees was similar to that found in lower canopy forest trees. However, the composition
of ant and beetle communities differed greatly between the agroforest and forest sites. Forest beetles suffered profoundly
from the conversion to agroforests: only 12.5% of the beetle species recorded in the forest sites were also found in the agroforests
and those species made up only 5% of all beetles collected from cacao. In contrast, forest ants were well represented in agroforests,
with 75% of all species encountered in the forest sites also occurring on cacao. The reduction of shade tree diversity had
no negative effect on ants and beetles on cacao trees. Beetle abundances and non-forest ant species richness even increased
with decreasing shade tree diversity. Thinning of the shade canopy was related to a decrease in richness of forest ant species
on cacao trees but not of beetles. The contrasting responses of ants and beetles to shade tree management emphasize that conservation
plans that focus on one taxonomic group may not work for others. Overall ant and beetle diversity can remain high in shaded
agroforests but the conservation of forest ants and beetles in particular depends primarily on the protection of natural forests,
which for forest ants can be complemented by the conservation of adjacent shaded cacao agroforests. 相似文献
73.
《L'Anthropologie》2022,126(1):102995
Preliminary conclusions from high-resolution microstratigraphical and taphonomical research suggest that Palaeolithic frequentation of the rock-shelter alternated with that of local fauna in the late Early (Lower) Pleistocene. 相似文献
74.
《L'Anthropologie》2022,126(3):103031
Turkey is one of the rich countries in terms of the Lower Palaeolithic period. The favourable climatic and environmental conditions and quality stone raw material resources in the Pleistocene period caused the country to be heavily occupied by the people of the Lower Palaeolithic. Turkey has biface and flake industries of the Lower Palaeolithic period. Biface industries are more common in open-air sites and are often linked to the Acheulean. Biface tools are only found in the deposits of Karain Cave. The eastern and south-eastern parts of Turkey are the densest regions in terms of biface industries. This density decreases towards the west. However, this general appearance may have resulted from the insufficient level of excavations and surveys of Palaeolithic archaeology throughout the country. In this article, we try to draw a general framework of the Lower Palaeolithic period in Turkey, based on the important Lower Palaeolithic settlements in the country. 相似文献
75.
Jean‐Bernard Dongmo Champlain Djieto‐Lordon Pierre Ngassam 《African Journal of Ecology》2015,53(3):312-319
Evidence of sexual dimorphism in body size and the existence of morphological differences were studied in the yellow‐whiskered Greenbul Andropadus latirostris. We measured fresh body weight and seven linear parameters of external morphology in mature individuals of this species from three localities in Cameroon and two localities in Ghana. Based on general linear model analysis, we showed that males are significantly larger than females. We applied a discriminant analysis on eight morphometric parameters to create two discriminant functions, one for each country. The overall rate of well‐classified birds was 93.3% for Cameroon and 92.7% for Ghana. Wing length was the most accurate character for separating the sexes in both study areas. Significant sexual size dimorphism might be explained by sexual selection on male competitive ability and intraspecific competition. We also found morphological divergence in this species between the two study areas, including marked differences in size of the beak. This work provides statistical evidence of a substantial sexual size dimorphism in A. latirostris and geographic variation in morphology. 相似文献
76.
Peter Schmid 《L'Anthropologie》2015,119(5):694-705
The Middle East is apparently the most important passage for the dispersal of early hominins. Numerous archeological sites prove the existence of hominin populations in this region, but despite these rich cultural remains, hominin fossils are very rare. In 1996, a hominin left parietal was found in an Acheulean context. In addition, the faunal remains indicate a steppe environment. What does this single cranial fragment tell us? Based on new publications and in particular on recent finds, the value of isolated elements is discussed. 相似文献
77.
The vertebrate fauna from the Lower Cretaceous Patuxent Formation of Virginia is composed of a single partial fish impression from the James River at Dutch Gap and a diverse tetrapod ichnofauna from near Fredericksburg that includes trace fossils made by frogs, turtles, theropods, sauropods, ankylosaurs, and ornithopods. The footprints occur on overbank deposits preserved locally within a fluvial braided-stream sequence that formed near the western border of the Early Cretaceous Atlantic Coastal Plain. 相似文献
78.
Cretorabus rasnitsynisp. n., belonging to the extinct subfamily Protorabinae of Carabidae, was described based on a well-preserved specimen from the Lower Cretaceous Yixian Formation of Yangshuwanzi, Inner Mongolia. The diagnostic characters forCretorabus are revised, and the key to species of the genus was presented. The fossil record of Protorabinae was summarized. Sinocarabus Hong, 1982 and Obesofemoria Hong, 1982 cannot be attributed to Protorabinae. 相似文献
79.
目的:对比分析应用新型静脉剥脱导管单次与分次手术治疗双下肢单纯性静脉曲张的疗效。方法:采用严格的纳入和排除标准选取我院2007年8月至2010年8月收治的双下肢单纯性静脉曲张患者53例,以接受采用法国Gamida公司新型静脉剥脱导管的大隐静脉高位结扎加剥脱手术次数不同分为两组。单次手术组:(28例)患者一次性接受双侧手术;分次手术组:(25例)患者接受单侧手术,1月后再入院接受对侧手术。结果:分次手术组两次手术时间总和较单次手术组手术时间长(P=0.034),而两组在术中失血量上无明显差异(P=0.550)。两组临床治愈率及出现并发症的几率相当(P〉0.05),但分次手术组的住院时间及住院费用均明显高于单次手术组(P〈0.001)。结论:应用新型静脉剥脱导管单次手术剥脱双下肢单纯性静脉曲张的疗效与分次手术相当,但在经济方面单次手术显示出明显的优势,值得推广。 相似文献
80.
目的:探讨尿动力学检查在了解慢性非细菌性前列腺炎/慢性骨盆疼痛综合征(Chronicabacterialprostatitis/chronicpelvicpain syndrome,CPPS)患者中下尿路症状(LUTS)产生原因的作用。方法:对36例难治性慢性前列腺炎/盆腔疼痛综合征患者行尿流动力学压力-流率测定,同步测定膀胱压、逼尿肌压、同步肌电图测定,了解其症状产生的原因。结果:36例患者中,尿动力学证实膀胱出口梗阻14例(39%);逼尿肌过度活动者8例,其中有7例与BOO同时存在;假性逼尿肌尿道外括约肌协同失调6例(16.7%);逼尿肌收缩力低下者5例(13.9%)。结论:对难治性CPPS患者进行尿动力学检查有助于对此类患者LUTS产生的原因进行鉴别,从而可以采取有针对性的治疗。 相似文献