野生绿孔雀生态学及保护生物学研究进展

绿孔雀(Pavo muticus)是我国国家I级重点保护野生动物, 也是中国传统文化中具有重要代表意义的物种。在历史上, 绿孔雀曾广泛分布于我国南部大部分地区, 但目前在国内只分布于云南省部分地区。在国外有绿孔雀分布的东南亚国家, 绿孔雀同样经历了从广布到局部甚至零星分布的严重退缩。关于野生绿孔雀生态学和种群现状的研究已开展了不少工作, 但仍有许多空缺; 而该物种面临的生存威胁给保护和管理工作带来了巨大挑战。本文通过梳理国内外野生绿孔雀生态学和保护生物学方面的研究, 阐述了绿孔雀在国内外种群和分布区的变迁与现状、栖息地选择、与同域分布物种的种间关系, 分析了主要的致危因素, 同时为今后的研究方向和保护措施提出了建议。现有研究显示: (1)绿孔雀在国内的种群数量已不足500只, 在东南亚主要分布于中南半岛的部分区域及印度尼西亚的爪哇岛; (2)绿孔雀对水源地有很强的依赖, 倾向于利用远离居民点的区域, 并偏爱利用生境开阔、旱季落叶的热带季雨林, 喜爱与大型有蹄类混群; (3)大型猫科动物可能是绿孔雀潜在的天敌; (4)偷猎和栖息地丧失是绿孔雀面临的最主要的致危因素。综上, 我们建议尽快建立起中国绿孔雀监测网络, 评估野生绿孔雀的种群动态, 识别不同区域绿孔雀的受胁因素, 并结合分子生物学等技术开展保护遗传学研究。在保护实践上, 应在目前中国野生绿孔雀分布较为集中、原生栖息地保存较为完整的红河(元江)中上游河谷地带建立自然保护区, 同时加强巡护工作, 启动栖息地恢复工程, 并杜绝在野生绿孔雀栖息地附近的蓝孔雀(Pavo cristatus)养殖。     

云南元江上游石羊江河谷绿孔雀不同季节觅食地选择

我们于2007年3-4月和10-11月在云南元江上游石羊江河谷绿孔雀(Pavo muticus imperator)的分布区内, 采用样线法和样方法调查了绿孔雀的觅食生境, 测定了21个生态因子。结果表明, 春季的觅食地利用样方距小路距离、乔木种类和藤本密度与对照样方存在显著差异, 而秋季的则不显著。生态因子比较和逻辑斯谛回归分析结果表明, 春、秋季绿孔雀均选择落果多、接近水源、坡度小、乔木的盖度和胸径大的地区作为觅食地。乔木和草本盖度, 距小路、居民点和林缘距离等是影响判别春、秋季觅食地选择的关键因子。概率和空间分布分析结果表明, 春、秋季绿孔雀在研究区内的概率分布呈明显的斑块状, 不同季节觅食活动位点均趋向于聚集分布, 分布区存在分离, 但有部分重叠。生态因子的主成分分析结果表明, 人为干扰对绿孔雀的影响大于安全和食物需求对它们自身的影响。隐蔽条件、食物和水源等关键性生态因子的配置和可获得性决定了绿孔雀的觅食地选择行为, 它对觅食地利用的不均匀是由于可利用资源分布不均匀所致, 而人为干扰压缩了可利用的适宜生境, 降低了利用程度。     

野生与笼养绿孔雀种群的随机扩增多态DNA研究

利用随机扩增多态DNA（RAPD）技术对野生14只和笼养18只绿孔雀（Pavo muticus）个体进行了种群遗传多样性分析。用23个随机引物,野生与笼养绿孔雀分别获得161和166个扩增片段,计算发现野生与笼养绿孔雀的种群内平均相对遗传距离分别是0.0555和0.1355,两种群间的为0.1635;两种群的Shannon多样性指数平均分别是0.4348和1.0163,有显著性差异。以上分析都显示野生绿孔雀的遗传多样性很低。用UPGMA法聚类显示两个种群都是分别来源于两个家系,可据此进行繁育管理。 Abstract:Random-amplified polymorphic DNA(RAPD) was used to investigate the genetic diversity of the population of 14 wild green peafowl and 18 captive green peafowl(pavo muticus).Total of 161 and 166 bands were obtained respectively,and 23 random primers were used to amplify the genomic DNA of the wild and captive green peafowls.The average relative hereditary distance of the wild and captive green peafowls is 0.0555 and 0.1355 respectively;and the Shannon diversity index is 0.4348 and 1.0163 respectively.There is a prominent differentia between the two populations by T-Test of HO.All the analyses above show that the genetic diversity is very low in wild green peafowl.It tells us that the two populations come from two families by using UPGMA,which can be useful in the breeding management in the future.     

Seasonal and diurnal use of eight different call types by Indian peafowl (<Emphasis Type="Italic">Pavo cristatus</Emphasis>)

The vocal displays of male Indian peafowl (Pavo cristatus) are thought to be sexually selected traits. To clarify the specific call types involved in breeding, as well as to provide basic information on the vocalisations of Indian peafowl, we conducted monthly daytime recordings in a large feral population in Japan. Based on 13,420 records, we identified seven different call types made only by males and six alarm calls uttered by both sexes. Furthermore, we found seasonal and diurnal changes in the calling activity of peafowl. Three of the male call types (keow, ka and hoot-call) were particularly important for breeding, as sexually mature males produced them only during the breeding season, in a similar diurnal pattern to other breeding behaviours. A digital video image relating to the article is available at .     

Electrocardiography of the short-tailed,leaf-nosed bat Carollia perspicillata

Thirty-three bats of the genus Carollia were anesthetized for routine physical exams with ketamine HCl. Each animal was placed in dorsal recumbency, and a six-lead electrocardiogram (ECG) was performed. ECG parameters were measured and intervals and deflections calculated. In addition, mean electrical axes in the frontal plane were calculated.     

A normal mode analysis of structural plasticity in the biomolecular motor F(1)-ATPase

Normal modes have been used to explore the inherent flexibility of the alpha, beta and gamma subunits of F(1)-ATPase in isolation and as part of the alpha(3)beta(3)gamma complex. It was found that the structural plasticity of the gamma and beta subunits, in particular, correlates with their functions. The N and C-terminal helices forming the coiled-coil domain of the gamma subunit are highly flexible in the isolated subunit, but more rigid in the alpha(3)beta(3)gamma complex due to interactions with other subunits. The globular domain of the gamma subunit is structurally relatively rigid when isolated and in the alpha(3)beta(3)gamma complex; this is important for its functional role in coupling the F(0) and F(1) complex of ATP synthase and in inducing the conformational changes of the beta subunits in synthesis. Most important, the character of the lowest-frequency modes of the beta(E) subunit is highly correlated with the large beta(E) --> beta(TP) transition. This holds for the C-terminal domain and the nucleotide-binding domain, which undergo significant conformational transitions in the functional cycle of F(1)-ATPase. This is most evident in the ligand-free beta(E) subunit; the flexibility in the nucleotide-binding domain is reduced somewhat in the beta(TP) subunit in the presence of Mg(2+).ATP. The low-frequency modes of the alpha(3)beta(3)gamma complex show that the motions of the globular domain of the gamma subunit and of the C-terminal and nucleotide binding domains of the beta(E) subunits are coupled, in accord with their function. Overall, the normal mode analysis reveals that F(1)-ATPase, like other macromolecular assemblies, has the intrinsic structural flexibility required for its function encoded in its sequence and three-dimensional structure. This inherent plasticity is an essential aspect of assuring a small free energy cost for the large-scale conformational transition that occurs in molecular motors.     

Comparison of three formal methods used to estimate the functional axis of rotation: an extensive in-vivo analysis performed on the knee joint

Estimating the main axis of rotation (AoR) of a human joint represents an important issue in biomechanics. This study compared three formal methods used to estimate functional AoR, namely a cylindrical fitting method, a mean helical axis transformation, and a symmetrical axis approach. These methods were tested on 106 subjects undergoing navigated total knee arthroplasty. AoR orientation in 3D and in the frontal and coronal planes provided by each method was compared to the transepicondylar axis direction. Although all the methods resulted effective, significant differences were identified among them, relatively to the orientation in 3D and in the frontal plane projection. This was probably due to the presence of secondary rotations during the first degrees of knee flexion.     

EST analysis of the scaly green flagellate Mesostigma viride (Streptophyta): Implications for the evolution of green plants (Viridiplantae)

Background  

The Viridiplantae (land plants and green algae) consist of two monophyletic lineages, the Chlorophyta and the Streptophyta. The Streptophyta include all embryophytes and a small but diverse group of freshwater algae traditionally known as the Charophyceae (e.g. Charales, Coleochaete and the Zygnematales). The only flagellate currently included in the Streptophyta is Mesostigma viride Lauterborn. To gain insight into the genome evolution in streptophytes, we have sequenced 10,395 ESTs from Mesostigma representing 3,300 independent contigs and compared the ESTs of Mesostigma with available plant genomes (Arabidopsis, Oryza, Chlamydomonas), with ESTs from the bryophyte Physcomitrella, the genome of the rhodophyte Cyanidioschyzon, the ESTs from the rhodophyte Porphyra, and the genome of the diatom Thalassiosira.     

The effects of high temperatures on individuals and populations of the green spruce aphid Elatobium abietinum (Walker)

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Full-size image (8K)

     

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