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1.
The Yunnan box turtle (Cuora yunnanensis, Boulenger, 1906), which has drawn much attention in conservation biology, was regarded as extinct since it was previously known only from 12 specimens collected in Yunnan, China, before 1908. Recently, live specimens have been discovered which are suggested to be C. yunnanensis. To determine whether the newly discovered specimens are really C. yunnanensis, we have established a molecular phylogeny, with a 1725-bp fragment of mitochondrial DNA, using samples from three live individuals of C. yunnanensis, together with sequence data from a museum specimen of C. yunnanensis (MNHN 1907.10) and other members of the genus Cuora. We found that the three newly discovered individuals and the old museum specimen of C. yunnanensis are very similar both in morphology and in mitochondrial DNA sequence, suggesting that the three new individuals are the very C. yunnanensis, and thus the species is not extinct. Our phylogenetic analysis also demonstrates that C. yunnanensis is not of recent hybrid origin, but rather represents a distinct evolutionary lineage.  相似文献   

2.
采用线粒体DNA细胞色素c氧化酶亚单位I(COI基因)部分序列,对我国西南地区15个地点共计240个云南切梢小蠹个体进行扩增和测序.研究发现,云南切梢小蠹不同地理种群间在线粒体基因组水平上具有不同程度的多样性,位于云南省中部地区的采样点遗传多样性较为丰富,而西北的丽江和宁蒗遗传多样性比较单一,四川的3个采样地在地理上很近,多样性也较为丰富;研究证实,云南切梢小蠹为单起源,源于云南中部,随后向四周扩散分布;云南切梢小蠹的分布与云南松分布息息相关,二者相辅相成,没有云南松的地方亦没有云南切梢小蠹.  相似文献   

3.
DNA sequences from the quagga, an extinct member of the horse family   总被引:18,自引:0,他引:18  
R Higuchi  B Bowman  M Freiberger  O A Ryder  A C Wilson 《Nature》1984,312(5991):282-284
To determine whether DNA survives and can be recovered from the remains of extinct creatures, we have examined dried muscle from a museum specimen of the quagga, a zebra-like species (Equus quagga) that became extinct in 1883 (ref. 1). We report that DNA was extracted from this tissue in amounts approaching 1% of that expected from fresh muscle, and that the DNA was of relatively low molecular weight. Among the many clones obtained from the quagga DNA, two containing pieces of mitochondrial DNA (mtDNA) were sequenced. These sequences, comprising 229 nucleotide pairs, differ by 12 base substitutions from the corresponding sequences of mtDNA from a mountain zebra, an extant member of the genus Equus. The number, nature and locations of the substitutions imply that there has been little or no postmortem modification of the quagga DNA sequences, and that the two species had a common ancestor 3-4 Myr ago, consistent with fossil evidence concerning the age of the genus Equus.  相似文献   

4.
广西存在安布闭壳龟的初步查考   总被引:1,自引:0,他引:1       下载免费PDF全文
作者于1991年在1992年两次带着安布闭壳龟的活动标本,深入上思县思阳镇,钦州市大直镇等地进行了野外调查和访问,获得安布闭壳龟的幼体背甲标本2个,一背甲标本1个。在调查中虽没获得活体标本,但两次调查所得资料表明广西的十万大山很可能生存有安布闭壳龟。  相似文献   

5.
干旱对云南易门县云南松生长的影响   总被引:2,自引:0,他引:2  
通过干季(3~5月)对云南易门县三个样地(谷地、山腰和山脊)云南松的调查和实验分析,了解干旱条件下,不同的土壤水分和物理状况对云南松生长的影响.发现土壤是制约云南松生长的主要限制因子.云南松针叶脯氨酸的含量可作为云南松抗旱的一个生理指标.  相似文献   

6.
以采自四川、甘肃、湖南等8省的9份牛角藓标本为材料,运用RAPD技术对牛角藓的分类修订进行研究.利用15条随机引物共获得134条清晰谱带,其中多态性条带占91.79%,牛角藓各标本间的遗传相似系数为0.703~0.870.结果显示:虽然9份牛角藓标本的形态特征差异非常大,但通过RAPD分析表明其为同一种.  相似文献   

7.
宽背虫(Bathynotus)这一传统早寒武世或寒武纪第2世晚期最重要的三叶虫属,广泛分布于全球寒武纪3个生物大区,为区域地层对比的标准化石.Bathynotus在贵州剑河八郎乌溜-曾家崖剖面凯里组下部极为丰富.该剖面已成为全球寒武系第2统和第3统界线层型候选剖面,表明凯里组是一个穿时的地层单元,其3个三叶虫带最下部一个带为Bathynotus holopygus-Ovatoryctocara granulata.经过逐层大量的化石标本采集统计证实,乌溜-曾家崖剖面宽背虫(Bathynotus)在距凯里组底部51.60 m处骤然绝灭,距寒武系第2统的顶界(距凯里组底52.80 m)只有1.20 m.本文就乌溜-曾家崖剖面凯里组下部宽背虫(Bathynotus)的数量分布变化认为其灭绝过程是逐步的.  相似文献   

8.
黄缘闭壳龟属世界珍稀濒危物种,中国重点野生保护动物.20世纪70年代前野生黄缘闭壳龟曾广泛分布于中国的河南、安徽、湖北、湖南、浙江、江苏、广西、台湾等省和琉球群岛,野生资源十分丰富,仅河南信阳大别山区的分布面积多达39万hm~2,野生种群数量约40万只.但自20世纪80年代后,随着盗猎强度的加剧,黄缘闭壳龟的分布区和栖息地遭到地毯式的搜索,猎捕手段的多样化及其过度猎捕致使黄缘闭壳龟野生资源日益枯竭.目前只在河南大别山区、安徽皖南山区、安徽皖西山区等地还有少量野生个体生存,稳定的黄缘闭壳龟野生种群仅分布于台湾和琉球群岛.导致黄缘闭壳龟野生资源濒危的原因主要是其性成熟周期长、种群繁殖力低、栖息地遭受干扰破坏等因素,另外,人类贪婪无尽地对其野生资源的索取是导致黄缘闭壳龟自然种群濒危灭绝的重要原因.加强黄缘闭壳龟保护区的建设与管理,加大打击盗猎行为,提高公众的保护意识,建立生态补偿机制,开展自然种群的恢复与重建是拯救黄缘闭壳龟濒危灭绝的有效措施.  相似文献   

9.
Huynen L  Millar CD  Scofield RP  Lambert DM 《Nature》2003,425(6954):175-178
Ancient DNA studies have typically used multi-copy mitochondrial DNA sequences. This is largely because single-locus nuclear genes have been difficult to recover from sub-fossil material, restricting the scope of ancient DNA research. Here, we have isolated single-locus nuclear DNA markers to assign the sex of 115 extinct moa and, in combination with a mitochondrial DNA phylogeny, tested competing hypotheses about the specific status of moa taxa. Moa were large ratite birds that showed extreme size variation both within and among species. For some taxa, this large variation was hypothesized to represent sexual dimorphism, while for others it was argued to reflect the existence of different species. Our results show that moa were characterized by extreme reverse sexual dimorphism and as a result we have been able to clarify the number of moa species. For example, we show that the three recognized 'species' of Dinornis comprised only two monophyletic groups and that two of these 'species' comprised individuals of one sex only. This study also illustrates that single-locus nuclear DNA sequences can be consistently recovered from ancient material.  相似文献   

10.
记述中国拟平腹蛛科1新纪录属——赫拉蛛属Heradion( Dankittipakul & Jocqué,2004)及1新纪录种——越南赫拉蛛Heradion paradiseum( Ono,2004).依据采自云南的1雄蛛标本对其进行了重新描述及绘图.观察标本保存在河北大学博物馆,文中测量单位为mm.  相似文献   

11.
地方高校动物标本馆建设与开放的研究   总被引:1,自引:0,他引:1  
从动物标本的来源、放置、陈列、数字化等方面研究了地方高校动物标本馆建设和开放的原因、目的和具体过程。论述了动物标本馆的日常管护及其在动物学教学和科研、科普等中所起的重要作用.  相似文献   

12.
In studying the genomes of extinct species, two principal limitations are typically the small quantities of endogenous ancient DNA and its degraded condition, even though products of up to 1,600 base pairs (bp) have been amplified in rare cases. Using small overlapping polymerase chain reaction products, longer stretches of sequences or even whole mitochondrial genomes can be reconstructed, but this approach is limited by the number of amplifications that can be performed from rare samples. Thus, even from well-studied Pleistocene species such as mammoths, ground sloths and cave bears, no DNA sequences of more than about 1,000 bp have been reconstructed. Here we report the complete mitochondrial genome sequence of the Pleistocene woolly mammoth Mammuthus primigenius. We used about 200 mg of bone and a new approach that allows the simultaneous retrieval of multiple sequences from small amounts of degraded DNA. Our phylogenetic analyses show that the mammoth was more closely related to the Asian than to the African elephant. However, the divergence of mammoth, African and Asian elephants occurred over a short time, corresponding to only about 7% of the total length of the phylogenetic tree for the three evolutionary lineages.  相似文献   

13.
采用聚合酶链式反应克隆黄河鮈线粒体细胞色素b基因 (Cyt b),首次报道了该基因的全长序列(1140bp,FJ904648) ,并与鮈属中其他6个物种的Cyt b 基因进行同源性比较,分析了碱基组成和变异情况,以马口鱼属的马口鱼和鯝属的云南鯝作为外群构建了ML和NJ系统发育树.遗传距离和分子系统学分析表明,黄河鮈与犬首鮈具有较低的遗传距离(6.30%),在系统发育树上两者聚在一起,提示黄河鮈与犬首鮈存在较近的亲缘关系.  相似文献   

14.
通过电泳检测和PCR扩增28SrDNA核基因序列的结果,比较了无水乙醇、75%乙醇、针插干制3种金龟甲虫标本的保存方式和SDS-蛋白酶K法、CTAB法、饱和NaCl法3种提取DNA方法.结果显示,SDS-蛋白酶K法、CTAB法提取3种保存方式的标本时,可成功提取DNA并有效扩增目的基因;饱和NaCl法仅能提取无水乙醇保存标本的DNA并扩增目的基因,而75%乙醇保存标本和干制标本的DNA提取和基因扩增均不理想.  相似文献   

15.
墨天牛属三个近缘种的RAPD分析   总被引:17,自引:2,他引:15  
应用RAPD(随机扩增的多态性DNA)技术,分析了墨天牛属三个近缘种-松墨天牛、云杉大墨天牛和云杉小墨天牛的DNA多态性。通过采用多种引物对同种天牛幼虫的浸渍标本和新鲜标本的DNA多态性研究,发现浸渍标本与新鲜标本DNA扩增后的电泳指纹图谱完全一致;同种害虫不同虫态间的DNA指纹图谱完全一致;三种随机引物可明显鉴别三种天牛幼虫。这为天牛近缘种的鉴定,尤其是天牛幼虫的鉴定提供了一种新方法。  相似文献   

16.
拟步甲昆虫基因组DNA提取的比较研究   总被引:10,自引:0,他引:10  
对拟步甲科8种昆虫的新鲜标本及无水乙醇浸泡标本,分别用SDS-蛋白酶K消化法和乙酸钾抽提法进行基因组总DNA的提取.经5次重复实验,结果表明,用两种方法均能从新鲜标本中获得较完整的DNA,且DNA得率较高;而对于无水乙醇保存的标本,提取出的DNA用琼脂糖凝胶电泳检测不出DNA条带,说明标本在保存过程中DNA可能发生了变化,致使提取出的DNA量太少或未分离出DNA.通过对比实验,分析原因,阐明了两种方法的优缺点,并提出了该类昆虫用于DNA提取的标本的保存方法.  相似文献   

17.
切梢小蠹属各种之前形态差异很小,种类鉴定困难.采用线粒体DNA细胞色素c氧化酶亚单位I(COI基因)部分序列,对5种切梢小蠹进行PCR扩增和测序.研究分析发现:华山松切梢小蠹与其他4种切梢小蠹存在明显的遗传分化,再次证明华山松切梢小蠹是1个新种;云南切梢小蠹与华山松切梢小蠹在各种分析数据结果都显示出很小的差异,但二者的寄主完全不同,这暗示着二者最初可能起源于同1个祖先,产生分化的原因可能是寄主的差异所致.通过探索5种切梢小蠹之间的关系,为其防控提供科学数据.  相似文献   

18.
根据文献记载以及对采自贵州省各县市地萼苔科Geocalycaceae植物标本(300余份)的鉴定,经统计贵州省地萼苔科植物现有18种l变种,其中中华裂萼苔Chiloscyphus sinensis、爽气裂萼苔C.fragrans为贵州新记录.根据各个种的形态特征,编制了该科的分种检索表,并对新记录种的主要形态特征进行了...  相似文献   

19.
Genetic evidence for Near-Eastern origins of European cattle   总被引:30,自引:0,他引:30  
The limited ranges of the wild progenitors of many of the primary European domestic species point to their origins further east in Anatolia or the fertile crescent. The wild ox (Bos primigenius), however, ranged widely and it is unknown whether it was domesticated within Europe as one feature of a local contribution to the farming economy. Here we examine mitochondrial DNA control-region sequence variation from 392 extant animals sampled from Europe, Africa and the Near East, and compare this with data from four extinct British wild oxen. The ancient sequences cluster tightly in a phylogenetic analysis and are clearly distinct from modern cattle. Network analysis of modern Bos taurus identifies four star-like clusters of haplotypes, with intra-cluster diversities that approximate to that expected from the time depth of domestic history. Notably, one of these clusters predominates in Europe and is one of three encountered at substantial frequency in the Near East. In contrast, African diversity is almost exclusively composed of a separate haplogroup, which is encountered only rarely elsewhere. These data provide strong support for a derived Near-Eastern origin for European cattle.  相似文献   

20.
近年来,在云南蝇科昆虫调查工作中,采集到了很多蝇科标本,在标本的检视中,首次发现了毛背棘蝇Phaonia villana的雌性标本。在原始文献中仅描述雄性,该种雌性过去一直没有做过系统描述。为此,对雌性毛背棘蝇外部形态进行了补充描述,并绘制了尾器特征图[1]。毛背棘蝇种团原本隶属于棕斑棘蝇种团,由于径脉结节腹面有毛,从而从后者分离出来,另立一个种团[2]。毛背棘蝇种团中国已知3种:褐端棘蝇Phaonia fusciapicalis Feng et Ma,2002、毛背棘蝇Phaonia villana Robineau-Desvoidy,1830和宝兴棘蝇Phaonia baoxingensis Feng et Ma,2002。研究标本均保存于沈阳师范大学昆虫研究所。  相似文献   

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