牙齿残留物反映的闽西新石器时代人类食谱

本项目对福建闽西地区奇和洞与南山两处新石器时代遗址出土古人类牙齿进行了表面残留物提取与鉴定,通过对其中淀粉粒残留物的种类与数量对比,讨论了全新世初期至中期闽西地区古人类对植物资源的利用方式。这些古人类牙齿表面包含四大类形态不同的淀粉粒:1)多面体形;2)圆形或椭圆形;3)圆锥形;4)水滴形。这些淀粉粒分别代表了禾本科植物种子、植物地下根茎部分和疑似的坚果类,这些都是古人类容易获得的野生食物资源,在新石器时代古人类的饮食中占据着重要的地位。     

史前古人类之间的基因交流及对当今现代人的影响

古DNA实验技术及高通量测序技术的出现和发展,使得直接从古老化石中进行遗传物质的提取及测序成为可能,与古人类相关的基因组学研究因此取得了一系列突破性进展,已灭绝的古老型人类(如:尼安德特人和丹尼索瓦人)与非洲以外现代人之间基因的相互影响已被诸多证据所证实。研究表明,在史前时期,早期现代人向非洲以外地区扩散时,遭遇到了现已灭绝的古老型人类,他们在同一时空内长期共存,并发生了基因交流,有一部分古老型人类基因因此流向了现代人,有些基因一直流传至今,对当今现代人的基因组成产生重大影响;此外,不同古老型人类之间也存在基因交流;而早期现代人也对部分古老型人类的基因组成造成了影响。化石与古DNA信息的证据均表明,史前各种人类之间的基因交流在多个地区发生多次,他们的基因交流共同构建了当今现代人的基因库,并在生理机能、形态和疾病发生率等方面对现代人造成了深远的影响。     

Rabbit mitochondrial DNA diversity from prehistoric to modern times

The mitochondrial genetic variability in European rabbit (Oryctolagus cuniculus) populations present in Europe and North Africa from 11,000 years ago to the present day has been analyzed using ancient DNA techniques. DNA was extracted from 90 rabbit bones found in 22 archaeological sites dated between the Mesolithic and recent times. Nucleotide sequences present in a variable 233-bp domain of the cytochrome b gene were compared to those present in modern-day rabbits. The results show that the structure of ancient populations of wild rabbit exhibited remarkable stability over time until the Middle Ages. At this time, a novel type of mtDNA molecule abruptly appears into most wild populations studied from France. This mtDNA type corresponds to that currently present in the domestic breeds of rabbit examined so far. The relative rapidity by which this mtDNA type established and its absence in all sites examined before 1,700 years ago lend support to the hypothesis that between 2,000 and 1,000 years ago, man may have favored the development, into all regions of France, of animals carrying this particular mtDNA molecule. The origin of such animals has still to be found: animals previously living outside of France or within France but in very restricted areas? This event was concomitant with the documented establishment of warrens after the tenth century a.d. in Europe.     

新石器时代人骨遗骸中古代DNA的提取及X—Y染色体同源基因片段的PCR扩增

从中国新石器时代人骨遗骸中提取出古代ＤＮＡ。通过聚合酶链式反应技术扩增得到Ｘ－Ｙ染色体上的单考贝同源基因片段。由于扩增的基因片段长度具有性别多态性,从而为古代人骨和牙齿提供了分子生物学的性别鉴定。     

辽东山地古石河冰缘地貌森林生态系统苔藓物种多样性研究

基于9个20 m×30 m森林群落样地的调查数据,采用物种丰富度、α和β多样性指数,对辽东山地古石河冰缘地貌不同林型石生、树生苔藓植物物种多样性进行定量研究,采用皮尔逊相关分析方法对其影响因素进行分析。结果显示,古石河冰缘地貌苔藓植物共有26科46属59种;不同林型石生、树生苔藓植物物种丰富度和α多样性指数均为:暗针叶林针阔混交林落叶阔叶林;石生苔藓植物β多样性指数最高为落叶阔叶林-针阔混交林间(0.44),最低为落叶阔叶林-暗针叶林间(0.33);树生苔藓植物β多样性指数最高为针阔混交林-暗针叶林间(0.40),最低为落叶阔叶林-暗针叶林间(0.25);分析表明,林冠层郁闭度、海拔高度是影响辽东山地古石河冰缘地貌森林生态系统苔藓物种多样性的重要因子。     

青藏高原鱼类区系特征及其形成的地史原因分析

本文以作者大量实地考察资料为基础,对青藏高原鱼类区系特征进行深入分析和归纳,提出青藏高原鱼类6科26属114种的名录及各水系间鱼类共有属种的比较图。首先阐述了青藏高原鱼类区系组成的单纯性与复杂水系的概况,进而找出青藏高原与新疆等干旱地区间的鱼类区系和高原内部各水系间的鱼类区系的相互联系。第二部分,通过分布特征的分析确定青藏高原鱼类分布的三大特点,即在外泄河流上有明显的地理分界;在东南外围水域中呈点状分布,在垂直高度上有明显的地带性。最后,基于区系特征的分析,联系有关古地理、古气候和鱼类化石资料,探讨了形成青藏高原鱼类区系的地史原因。认为适应于温暖水域生活的原始鲃类和鳅类,在早第三纪时已广布于东亚和中亚地区。青藏高原现代鱼类区系不是由一个起源中心辐射或跨阻传布所形成的,而是通过喜马拉雅运动的三次重大地质历史事件产生隔离,导致青藏高原鱼类与其它地区鱼类的分离而形成的,其分别是:1.喜马拉雅地槽闭合引起“西康群山”再次隆起构成中亚与东亚鱼类区系的分离;2.喜马拉雅山隆起引起中亚与南亚鱼类区系间分离;3.阿尔金山等山脉再度隆起构成中亚地区青藏高原鱼类区系的分离,最后完成青藏高原这一独特的鱼类区系的雏形。 此外也论述了青藏高原鱼类区系东部分界线实际     

A two-way gas transport system in Nelumbo nucifera

Abstract The aquatic vascular plant Nelumbo nucifera Gaertn. is able to improve its oxygen supply to the submerged and buried organs by a thermo-osmotic gas transport. Investigations with tracer gas and oxygen measurements have shown that thermo-osmotic gas transport exists in N. nucifera when there is a temperature difference between the lacunar air of the leaves and the surrounding atmosphere. The gas transport was increased by up to 935% when a temperature difference of 2.9 ± 1.0 K was detected. Lacunar pressure of up to 166 ± 44 Pa was measured in both young and old leaves. In contrast to the flow-through ventilation system recently described for Nuphar lutea and Nymphoides peltata, a two-way flow in separate air canals in the petioles of both young and old Nelumbo leaves may carry oxygen-rich air down to the rhizome and excess air back to the atmosphere. Anatomical investigations have shown that, in Nelumbo, the two largest air canals of the petiole end directly under the mesh system of the centre plate. These large air canals are proposed to be predominant in the upward flow of air in sunlight. The other air canals of the petiole veer into the leaf blade well below the centre plate. The gas flow system through fresh leaves may carry as much as 10.3 ± 4.5 cm³ air per minute to the buried rhizome.     

Anthropology of the Late Period cemetery in the Tomb of King Horemheb at Saqqara (Egypt) (preliminary report)

Anthropological material unearthed by the excavation of the Egypt Exploration Society (London) in the Tomb of King Horemheb at Saqqara consists of original burials dated 14th cent. B.C., of a series of 18 individuals dated 13th cent. B.C. and of a large amount of material (seven burials and a lot of scattered isolated bones) from a secondary cemetery dated Late Period. In it the total number of individuals was determined as 260, divided into 37.3% immatures and 62.7% adults, which consist of 60.7% males and 39.3% females. The mean age at death was for the whole series 24.1 years, for adult males 33.3 years and for adult females 29.4 years. In all metric features a well-cut sexual dimorphism is apparent and a similarity with a contemporary nearly located series from the Mastaba of Ptahshepses at Abusir. The average stature reconstructed by the Negro equations of Trotter and Gleser equals 166.5 cm for males and 154.7 cm for females. Cranioscopic, epigenetic and osteoscopic features, however, showed many differences between the Horemheb and the Ptahshepses series. The paleopathological study revealed cases of traumatism, inflammations, degenerative osteoarthropathies, benign as well as malign tumours, anaemias, congenital anomalies, senile changes and dental diseases.     

The ancient woodland concept as a practical conservation tool in Great Britain

In the 1980s the Nature Conservancy Council created an ancient woodland inventory showing all woods in Great Britain (GB) greater than 2 ha that were believed to have had woodland habitat cover continuously from 1600. Subsequently these lists have been maintained as three separate inventories by NCC's successors, English Nature (now Natural England), Countryside Council for Wales and Scottish Natural Heritage. This paper outlines the concept of ancient woodland as it has developed in GB, and how this idea gave rise to the ancient woodland inventories. The criteria used in compiling the inventories are discussed, including the inception dates and the threshold size, and the difference between ancient woodland and parkland. The inventories have been digitised for use with Geographic Information Systems (GIS), which has made them more accessible to planners and nature conservation bodies; however, the digitising process is more precise than the original definition of the boundaries of the ancient woodland. The three different countries have approached this issue slightly differently, taking account of the differing landscapes within which their ancient woodland exists. As the inventory developed, new legislation has also been brought into play to protect ancient woodland further. The inventory currently lacks detailed information concerning the condition or type of wood, beyond its semi-natural or plantation status. Ascertaining, and then maintaining, the condition of ancient woodland in Great Britain will be a major challenge for the future.     

The flickering genes of the last mammoths

Woolly mammoths, Mammuthus primigenius, are arguably the most iconic of the extinct Pleistocene megafauna, and an abundance of large permafrost‐embedded bone and ivory material ( Fig. 1 ) means they were also among the first to yield credible DNA sequences ( Hagelberg et al. 1994 ; Hoss et al. 1994 ). Despite mammoth remains being numerous throughout northern Eurasia and North America, both the earliest and most recent fossils are found in northeast Siberia, with the last known population being confined to Wrangel Island in the Arctic Ocean from around 10,000 years ago until their extinction around 4,000 years ago. The extent to which these Holocene mammoths were descended from the Pleistocene populations of Wrangel Island and the demographic nature of their terminal decline have, until now, remained something of a mystery. In this issue of Molecular Ecology, Nyström et al. (2012) report the first use of autosomal variation to track the decline of the last mammoths and, in doing so, take a significant step towards resolving these questions. The authors genotyped four microsatellite loci in 59 Pleistocene and Holocene mammoths from Wrangel Island and Chukotka in mainland northeastern Siberia and showed that while the Pleistocene‐to‐Holocene transition is associated with a significant reduction in genetic diversity, subsequent levels of variation remain constant until extinction. Such a pattern is somewhat surprising as it indicates that while the last mammoths were confined to only a few Arctic islands, their final extinction on Wrangel Island was not a gradual process resulting from loss of genetic diversity/inbreeding. Instead, it seems they maintained a viable effective population size of around 500 until near their presumably rapid extinction. While the ultimate agent of mammoth extinction remains unknown, the work of Nyström et al. (2012) . suggests that we should be looking for something sudden, like a rapid change in climate/ecology or perhaps the arrival of humans.

Figure 1 Open in figure viewer PowerPoint Sergey Vartanyan during field collection, holding a woolly mammoth tusk found along a river embankment in northeast Siberia (photographer: Diana Solovyeva).