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中国干旱地区啮齿动物物种分布的区域分异   总被引:8,自引:0,他引:8  
周立志  马勇  叶晓堤 《动物学报》2002,48(2):183-194
搜集整理我国干旱地区啮齿动物地理分布数据,通过生境分析,确定啮齿动物分布区。基于GIS技术,以面积约为6470km^2的766个栅格收集我国干旱地区啮齿动物的二元分布数据,采用多元分析的分层聚类方法,依据欧氏距离平方值,将地理分布单元划分为若干个组。结果表明,当欧氏距离平方值分别为11.379,17.068,22.758和28.447时,766个地理分布单元依次可分为30,9,5和3个组。分布单元组的物种组成比较和生态型分析表明;(1)在我国干旱地区的海拔较低地带,景观自东向西由草原,荒漠草原过渡到荒漠,地理分布单元组亦呈现相应的分布格局,喜湿的物种逐渐减少,耐旱的种类增加;(2) 藏高原,帕米尔高原寒漠与蒙新温性和暖温性荒漠啮齿动物物种数和组成相近,物种多样性近;(3)阿尔泰山地及南麓平原啮齿动物组成较为特殊,寒湿啮齿动物成份最高;(4)东祁连山地及其北麓以及分犁谷地,额敏谷地,伊犁天山,准噶尔界山及东麓山前平均的啮齿动物成份较为复杂,物种多样性较高。我国干旱地区东部啮齿动物的物种密度和多样性高于西部,但在东部草原和西部荒漠之间的过渡区物种密度较高,表现出的种生态地理分布的边缘效应,体现干旱区啮齿动物物种分布与生物群落地带性分布以及山地和高原等特殊环境非地带性分布的适应关系。蒙新温性荒漠区和青藏高原寒漠区的啮齿动物在区系组成上有一定的历史渊源。  相似文献   
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Despite the importance of saliva in the regulation of oral cavity homeostasis, few studies have been conducted to quantitatively compare the saliva of different mammal species. Aiming to define a proteome signature of mammals’ saliva, an in‐depth SDS‐PAGE–LC coupled to MS/MS (GeLC–MS/MS) approach was used to characterize the saliva from primates (human), carnivores (dog), glires (rat and rabbit), and ungulates (sheep, cattle, horse). Despite the high variability in the number of distinct proteins identified per species, most protein families were shared by the mammals studied with the exception of cattle and horse. Alpha‐amylase is an example that seems to reflect the natural selection related to digestion efficacy and food recognition. Casein protein family was identified in all species but human, suggesting an alternative to statherin in the protection of hard tissues. Overall, data suggest that different proteins might assure a similar role in the regulation of oral cavity homeostasis, potentially explaining the specific mammals’ salivary proteome signature. Moreover, some protein families were identified for the first time in the saliva of some species, the presence of proline‐rich proteins in rabbit's saliva being a good example.  相似文献   
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将新疆北部 62种啮齿动物在新疆北部 6个动物地理省中有或无分布作为二元状态 ,用联合系数来表征啮齿动物地理省间啮齿类种类组成的相似程度 ,以类平均法进行聚类。聚类结果表明啮齿类在新疆北部各动物地理省的分布主要受各种生态因子的影响。还探讨了分布聚类与动物地理省区划的关系  相似文献   
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命名了中古新世的一个啮型类新属种——胡氏敏兽(Mina hui gen.et sp.nov.)。新属种的正型标本为可能属于同一个体的前颌骨和上颌骨,采自安徽省潜山县古井乡傅家山嘴中古新统望虎墩组上段上部。属名来源于周明镇先生的曾用名周敏,以纪念他对我国古新世生物地层和哺乳动物研究的杰出贡献;种名源自胡耀明博士,他为潜山哺乳动物的采集和研究做出过重要贡献。胡氏敏兽的特征如下:中等大小的模鼠兔类,上齿列齿式2·0·3·3;第一对门齿(d12)增大,无齿根、终生生长,釉质层双层,仅限于唇侧,表面无纵向浅沟;上颊齿列外缘显著凸出;颧弓前根后缘位于M1—M2之间,眶下孔位置低。以传统的模鼠兔目(Mimotonida)而论,它包括两个科:单型科模鼠兔科(Mimotonidae)只有模鼠兔(Mimotona)一属;模兔科(Mimolagidae)则包括模兔(Mimolagus),Gomphos,Anatolimys,敏兽和可能的Amar。在已知模鼠兔类中,模鼠兔很可能代表原始的兔形类祖先的"形态型",而模兔科则代表向兔形类进化的分支上分化出来的旁枝。晓鼠(Heomys)、模鼠兔和敏兽的共存说明啮形类在中古新世时已经分化。  相似文献   
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Rodentia (e.g., mice, rats, dormice, squirrels, and guinea pigs) and Lagomorpha (e.g., rabbits, hares, and pikas) are usually grouped into the Glires. Status of this controversial superorder has been evaluated using morphology, paleontology, and mitochondrial plus nuclear DNA sequences. This growing corpus of data has been favoring the monophyly of Glires. Recently, Misawa and Janke [Mol. Phylogenet. Evol. 28 (2003) 320] analyzed the 6441 amino acids of 20 nuclear proteins for six placental mammals (rat, mouse, rabbit, human, cattle, and dog) and two outgroups (chicken and xenopus), and observed a basal position of the two murine rodents among the former. They concluded that "the Glires hypothesis was rejected." We here reanalyzed [loc. cit.] data set under maximum likelihood and Bayesian tree-building approaches, using phylogenetic models that take into account among-site variation in evolutionary rates and branch-length variation among proteins. Our observations support both the association of rodents and lagomorphs and the monophyly of Euarchontoglires (=Supraprimates) as the most likely explanation of the protein alignments. We conducted simulation studies to evaluate the appropriateness of lissamphibian and avian outgroups to root the placental tree. When the outgroup-to-ingroup evolutionary distance increases, maximum parsimony roots the topology along the long Mus-Rattus branch. Maximum likelihood, in contrast, roots the topology along different branches as a function of their length. Maximum likelihood appears less sensitive to the "long-branch attraction artifact" than is parsimony. Our phylogenetic conclusions were confirmed by the analysis of a different protein data set using a similar sample of species but different outgroups. We also tested the effect of the addition of afrotherian and xenarthran taxa. Using the linearized tree method, [loc. cit.] estimated that mice and rats diverged about 35 million years ago. Molecular dating based on the Bayesian relaxed molecular clock method suggests that the 95% credibility interval for the split between mice and rats is 7-17 Mya. We here emphasize the need for appropriate models of sequence evolution (matrices of amino acid replacement, taking into account among-site rate variation, and independent parameters across independent protein partitions) and for a taxonomically broad sample, and conclude on the likelihood that rodents and lagomorphs together constitute a monophyletic group (Glires).  相似文献   
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河南省啮齿动物地理分布的聚类研究   总被引:7,自引:0,他引:7  
路纪琪等[1 ]对河南省啮齿动物区系与区划进行了研究 ,把河南省已知的 32种啮齿动物区系划分为豫西北太行山地森林省、豫西黄土台地农作省、豫东豫北平原及南阳盆地农作省、豫西伏牛山地森林省、淮南冲积平原农作省和豫南桐柏 大别山地森林省共 6个动物地理省。因为毛耳飞鼠(Belomys pearsonii )、中华鼢鼠(Myospalax fontaneri)、针毛鼠 (Rattusfulvescens) 3种动物尚无标本考证 ,故本文所列河南省啮齿动物计 2 9种。另据马勇等[2 ]研究 ,认为应恢复绒鼠平属 (Caryomys)的分…  相似文献   
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河南省啮齿动物区系与区划研究   总被引:9,自引:0,他引:9  
路纪琪  王廷正 《兽类学报》1996,16(2):119-128
河南省啮齿动物计有32种,隶属于2目7科4亚科。本文在野外考察的基础上,结合前人的工作,对河南省啮齿动物区系种的组成和区系特征进行了分析,并与邻近地区作了比较,就啮齿动物进行了区划研究,将河南全境划分成6个三级省、8个四级州;在区划中给出了防治建议;另就古北界与东洋界在河南省境内的分界线问题提出了新的看法。  相似文献   
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